Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.
The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)
Chromosomes, Human, Pair 1
Chromosomes, Human, Pair 7
Chromosomes, Human, Pair 11
Chromosomes, Human, Pair 17
Chromosomes, Human, Pair 6
Chromosomes, Human, Pair 9
Chromosomes, Human, Pair 21
Chromosomes, Human, 6-12 and X
Chromosomes, Human, Pair 2
Chromosomes, Human, Pair 16
Chromosomes, Human, Pair 22
Chromosomes, Human, Pair 13
Chromosomes, Human, Pair 4
Chromosomes, Human, Pair 10
Chromosomes, Human, Y
Chromosomes, Human, Pair 8
Chromosomes, Human, Pair 19
Chromosomes, Artificial, Bacterial
Chromosomes, Human, X
Chromosomes, Human, 1-3
Chromosomes, Human, Pair 12
A technique for visualizing CHROMOSOME ABERRATIONS using fluorescently labeled DNA probes which are hybridized to chromosomal DNA. Multiple fluorochromes may be attached to the probes. Upon hybridization, this produces a multicolored, or painted, effect with a unique color at each site of hybridization. This technique may also be used to identify cross-species homology by labeling probes from one species for hybridization with chromosomes from another species.
Chromosomes, Human, Pair 5
Chromosomes, Human, Pair 15
Chromosomes, Human, Pair 14
Chromosomes, Human, Pair 18
Chromosomes, Human, 16-18
In Situ Hybridization, Fluorescence
Chromosomes, Human, Pair 20
Chromosomes, Artificial, Yeast
Chromosomes in which fragments of exogenous DNA ranging in length up to several hundred kilobase pairs have been cloned into yeast through ligation to vector sequences. These artificial chromosomes are used extensively in molecular biology for the construction of comprehensive genomic libraries of higher organisms.
Chromosomes, Human, 13-15
Chromosomes, Human, 21-22 and Y
Chromosomes, Human, 4-5
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
X Chromosome Inactivation
Chromosomes, Human, 19-20
The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).
Chromosomes, Artificial, Human
Nucleic Acid Hybridization
Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A technique with which an unknown region of a chromosome can be explored. It is generally used to isolate a locus of interest for which no probe is available but that is known to be linked to a gene which has been identified and cloned. A fragment containing a known gene is selected and used as a probe to identify other overlapping fragments which contain the same gene. The nucleotide sequences of these fragments can then be characterized. This process continues for the length of the chromosome.
Chromosomal Proteins, Non-Histone
Amino Acid Sequence
Sequence Analysis, DNA
Highly repetitive DNA sequences found in HETEROCHROMATIN, mainly near centromeres. They are composed of simple sequences (very short) (see MINISATELLITE REPEATS) repeated in tandem many times to form large blocks of sequence. Additionally, following the accumulation of mutations, these blocks of repeats have been repeated in tandem themselves. The degree of repetition is on the order of 1000 to 10 million at each locus. Loci are few, usually one or two per chromosome. They were called satellites since in density gradients, they often sediment as distinct, satellite bands separate from the bulk of genomic DNA owing to a distinct BASE COMPOSITION.
Species- or subspecies-specific DNA (including COMPLEMENTARY DNA; conserved genes, whole chromosomes, or whole genomes) used in hybridization studies in order to identify microorganisms, to measure DNA-DNA homologies, to group subspecies, etc. The DNA probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the DNA probe include the radioisotope labels 32P and 125I and the chemical label biotin. The use of DNA probes provides a specific, sensitive, rapid, and inexpensive replacement for cell culture techniques for diagnosing infections.
Polymerase Chain Reaction
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Repetitive Sequences, Nucleic Acid
Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).
Either of the two longitudinally adjacent threads formed when a eukaryotic chromosome replicates prior to mitosis. The chromatids are held together at the centromere. Sister chromatids are derived from the same chromosome. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)
The number of copies of a given gene present in the cell of an organism. An increase in gene dosage (by GENE DUPLICATION for example) can result in higher levels of gene product formation. GENE DOSAGE COMPENSATION mechanisms result in adjustments to the level GENE EXPRESSION when there are changes or differences in gene dosage.
Loss of Heterozygosity
Cell Cycle Proteins
Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.
The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.
Chromosome Fragile Sites
Specific loci that show up during KARYOTYPING as a gap (an uncondensed stretch in closer views) on a CHROMATID arm after culturing cells under specific conditions. These sites are associated with an increase in CHROMOSOME FRAGILITY. They are classified as common or rare, and by the specific culture conditions under which they develop. Fragile site loci are named by the letters "FRA" followed by a designation for the specific chromosome, and a letter which refers to which fragile site of that chromosome (e.g. FRAXA refers to fragile site A on the X chromosome. It is a rare, folic acid-sensitive fragile site associated with FRAGILE X SYNDROME.)
Sex Chromosome Disorders
Sequence Tagged Sites
Short tracts of DNA sequence that are used as landmarks in GENOME mapping. In most instances, 200 to 500 base pairs of sequence define a Sequence Tagged Site (STS) that is operationally unique in the human genome (i.e., can be specifically detected by the polymerase chain reaction in the presence of all other genomic sequences). The overwhelming advantage of STSs over mapping landmarks defined in other ways is that the means of testing for the presence of a particular STS can be completely described as information in a database.
Polymorphism, Restriction Fragment Length
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Polymorphism, Single Nucleotide
DNA Transposable Elements
Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.
Genetic Predisposition to Disease
An aberrant form of human CHROMOSOME 22 characterized by translocation of the distal end of chromosome 9 from 9q34, to the long arm of chromosome 22 at 22q11. It is present in the bone marrow cells of 80 to 90 per cent of patients with chronic myelocytic leukemia (LEUKEMIA, MYELOGENOUS, CHRONIC, BCR-ABL POSITIVE).
Sequence Homology, Nucleic Acid
Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Sequence Homology, Amino Acid
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Specific regions that are mapped within a GENOME. Genetic loci are usually identified with a shorthand notation that indicates the chromosome number and the position of a specific band along the P or Q arm of the chromosome where they are found. For example the locus 6p21 is found within band 21 of the P-arm of CHROMOSOME 6. Many well known genetic loci are also known by common names that are associated with a genetic function or HEREDITARY DISEASE.
A selective increase in the number of copies of a gene coding for a specific protein without a proportional increase in other genes. It occurs naturally via the excision of a copy of the repeating sequence from the chromosome and its extrachromosomal replication in a plasmid, or via the production of an RNA transcript of the entire repeating sequence of ribosomal RNA followed by the reverse transcription of the molecule to produce an additional copy of the original DNA sequence. Laboratory techniques have been introduced for inducing disproportional replication by unequal crossing over, uptake of DNA from lysed cells, or generation of extrachromosomal sequences from rolling circle replication.
Genes whose loss of function or gain of function MUTATION leads to the death of the carrier prior to maturity. They may be essential genes (GENES, ESSENTIAL) required for viability, or genes which cause a block of function of an essential gene at a time when the essential gene function is required for viability.
Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)
Sister Chromatid Exchange
An exchange of segments between the sister chromatids of a chromosome, either between the sister chromatids of a meiotic tetrad or between the sister chromatids of a duplicated somatic chromosome. Its frequency is increased by ultraviolet and ionizing radiation and other mutagenic agents and is particularly high in BLOOM SYNDROME.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Genes, Tumor Suppressor
A family of highly conserved serine-threonine kinases that are involved in the regulation of MITOSIS. They are involved in many aspects of cell division, including centrosome duplication, SPINDLE APPARATUS formation, chromosome alignment, attachment to the spindle, checkpoint activation, and CYTOKINESIS.
A chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21. Clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, Simian crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)
Meiotic Prophase I
Quantitative Trait, Heritable
Radiation Hybrid Mapping
A method for ordering genetic loci along CHROMOSOMES. The method involves fusing irradiated donor cells with host cells from another species. Following cell fusion, fragments of DNA from the irradiated cells become integrated into the chromosomes of the host cells. Molecular probing of DNA obtained from the fused cells is used to determine if two or more genetic loci are located within the same fragment of donor cell DNA.
The presence of apparently similar characters for which the genetic evidence indicates that different genes or different genetic mechanisms are involved in different pedigrees. In clinical settings genetic heterogeneity refers to the presence of a variety of genetic defects which cause the same disease, often due to mutations at different loci on the same gene, a finding common to many human diseases including ALZHEIMER DISEASE; CYSTIC FIBROSIS; LIPOPROTEIN LIPASE DEFICIENCY, FAMILIAL; and POLYCYSTIC KIDNEY DISEASES. (Rieger, et al., Glossary of Genetics: Classical and Molecular, 5th ed; Segen, Dictionary of Modern Medicine, 1992)
DNA Restriction Enzymes
Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.
Sex Chromosome Disorders of Sex Development
The nuclear receptor superfamily has undergone extensive proliferation and diversification in nematodes. (1/6287)The nuclear receptor (NR) superfamily is the most abundant class of transcriptional regulators encoded in the Caenorhabditis elegans genome, with >200 predicted genes revealed by the screens and analysis of genomic sequence reported here. This is the largest number of NR genes yet described from a single species, although our analysis of available genomic sequence from the related nematode Caenorhabditis briggsae indicates that it also has a large number. Existing data demonstrate expression for 25% of the C. elegans NR sequences. Sequence conservation and statistical arguments suggest that the majority represent functional genes. An analysis of these genes based on the DNA-binding domain motif revealed that several NR classes conserved in both vertebrates and insects are also represented among the nematode genes, consistent with the existence of ancient NR classes shared among most, and perhaps all, metazoans. Most of the nematode NR sequences, however, are distinct from those currently known in other phyla, and reveal a previously unobserved diversity within the NR superfamily. In C. elegans, extensive proliferation and diversification of NR sequences have occurred on chromosome V, accounting for > 50% of the predicted NR genes. (+info)
Analysis of two cosmid clones from chromosome 4 of Drosophila melanogaster reveals two new genes amid an unusual arrangement of repeated sequences. (2/6287)Chromosome 4 from Drosophila melanogaster has several unusual features that distinguish it from the other chromosomes. These include a diffuse appearance in salivary gland polytene chromosomes, an absence of recombination, and the variegated expression of P-element transgenes. As part of a larger project to understand these properties, we are assembling a physical map of this chromosome. Here we report the sequence of two cosmids representing approximately 5% of the polytenized region. Both cosmid clones contain numerous repeated DNA sequences, as identified by cross hybridization with labeled genomic DNA, BLAST searches, and dot matrix analysis, which are positioned between and within the transcribed sequences. The repetitive sequences include three copies of the mobile element Hoppel, one copy of the mobile element HB, and 18 DINE repeats. DINE is a novel, short repeated sequence dispersed throughout both cosmid sequences. One cosmid includes the previously described cubitus interruptus (ci) gene and two new genes: that a gene with a predicted amino acid sequence similar to ribosomal protein S3a which is consistent with the Minute(4)101 locus thought to be in the region, and a novel member of the protein family that includes plexin and met-hepatocyte growth factor receptor. The other cosmid contains only the two short 5'-most exons from the zinc-finger-homolog-2 (zfh-2) gene. This is the first extensive sequence analysis of noncoding DNA from chromosome 4. The distribution of the various repeats suggests its organization is similar to the beta-heterochromatic regions near the base of the major chromosome arms. Such a pattern may account for the diffuse banding of the polytene chromosome 4 and the variegation of many P-element transgenes on the chromosome. (+info)
Optical mapping of Plasmodium falciparum chromosome 2. (3/6287)Detailed restriction maps of microbial genomes are a valuable resource in genome sequencing studies but are toilsome to construct by contig construction of maps derived from cloned DNA. Analysis of genomic DNA enables large stretches of the genome to be mapped and circumvents library construction and associated cloning artifacts. We used pulsed-field gel electrophoresis purified Plasmodium falciparum chromosome 2 DNA as the starting material for optical mapping, a system for making ordered restriction maps from ensembles of individual DNA molecules. DNA molecules were bound to derivatized glass surfaces, cleaved with NheI or BamHI, and imaged by digital fluorescence microscopy. Large pieces of the chromosome containing ordered DNA restriction fragments were mapped. Maps were assembled from 50 molecules producing an average contig depth of 15 molecules and high-resolution restriction maps covering the entire chromosome. Chromosome 2 was found to be 976 kb by optical mapping with NheI, and 946 kb with BamHI, which compares closely to the published size of 947 kb from large-scale sequencing. The maps were used to further verify assemblies from the plasmid library used for sequencing. Maps generated in silico from the sequence data were compared to the optical mapping data, and good correspondence was found. Such high-resolution restriction maps may become an indispensable resource for large-scale genome sequencing projects. (+info)
Telomeric repeats on small polydisperse circular DNA (spcDNA) and genomic instability. (4/6287)Small polydisperse circular DNA (spcDNA) is a heterogeneous population of extrachromosomal circular molecules present in a large variety of eukaryotic cells. Elevated amounts of total spcDNA are related to endogenous and induced genomic instability in rodent and human cells. We suggested spcDNA as a novel marker for genomic instability, and speculated that spcDNA might serve as a mutator. In this study, we examine the presence of telomeric sequences on spcDNA. We report for the first time the appearance of telomeric repeats in spcDNA molecules (tel-spcDNA) in rodent and human cells. Restriction enzyme analysis indicates that tel-spcDNA molecules harbor mostly, if not exclusively, telomeric repeats. In rodent cells, tel-spcDNA levels are higher in transformed than in normal cells and are enhanced by treatment with carcinogen. Tel-spcDNA is also detected in some human tumors and cell lines, but not in others. We suggest, that its levels in human cells may be primarily related to the amount of the chromosomal telomeric sequences. Tel-spcDNA may serve as a unique mutator, through specific mechanisms related to the telomeric repeats, which distinguish it from the total heterogeneous spcDNA population. It may affect telomere dynamics and genomic instability by clastogenic events, alterations of telomere size and sequestration of telomeric proteins. (+info)
Structure and inheritance of some heterozygous Robertsonian translocation in man. (5/6287)Banding studies in 25 Robertsonian translocations showed that all could be interpreted as stable dicentrics. The mechanism for their stability is likely to be the proximity of their centromeres but centromeric suppression could also have a role. In many of these dicentric translocations, discontinuous centromeric suppression, as indicated by chromatid separation at one of the centromeric regions, was observed in C-banded preparations. A further observation of undefined relation to the first was that the ratio of the two constitutive centromeric heterochromatin (CCH) regions from the component chromosomes of the translocations was variable in the same translocation type, e.g. t(13;14). It is proposed that this ratio may influence the segregation ratio. Abnormal spermatogenesis is suggested as the likely mechanism for the difference in the proportion of aneuploid offspring in the progeny of maternal and paternal heterozygotes. Neither of the t dic(21;21)s could be interpreted as isochromosomes. It is proposed that Robertsonian fusion translocations be defined as stable, dicentric, whole-arm translocations, with both centromeres in a median position and resulting in the loss of a small acentric fragment during this formation. It is suggested that they occur at high frequency between telocentric or, as in man, certain acrocentric chromosomes because of some intrinsic property of those chromosomes not possessed by metacentric chromosomes and mediated by interphase association of centromeres. (+info)
The RNA-editing enzyme ADAR1 is localized to the nascent ribonucleoprotein matrix on Xenopus lampbrush chromosomes but specifically associates with an atypical loop. (6/6287)Double-stranded RNA adenosine deaminase (ADAR1, dsRAD, DRADA) converts adenosines to inosines in double-stranded RNAs. Few candidate substrates for ADAR1 editing are known at this point and it is not known how substrate recognition is achieved. In some cases editing sites are defined by basepaired regions formed between intronic and exonic sequences, suggesting that the enzyme might function cotranscriptionally. We have isolated two variants of Xenopus laevis ADAR1 for which no editing substrates are currently known. We demonstrate that both variants of the enzyme are associated with transcriptionally active chromosome loops suggesting that the enzyme acts cotranscriptionally. The widespread distribution of the protein along the entire chromosome indicates that ADAR1 associates with the RNP matrix in a substrate-independent manner. Inhibition of splicing, another cotranscriptional process, does not affect the chromosomal localization of ADAR1. Furthermore, we can show that the enzyme is dramatically enriched on a special RNA-containing loop that seems transcriptionally silent. Detailed analysis of this loop suggests that it might represent a site of ADAR1 storage or a site where active RNA editing is taking place. Finally, mutational analysis of ADAR1 demonstrates that a putative Z-DNA binding domain present in ADAR1 is not required for chromosomal targeting of the protein. (+info)
Transient gene asymmetry during sporulation and establishment of cell specificity in Bacillus subtilis. (7/6287)Sporulation in Bacillus subtilis is initiated by an asymmetric division generating two cells of different size and fate. During a short interval, the smaller forespore harbors only 30% of the chromosome until the remaining part is translocated across the septum. We demonstrate that moving the gene for sigmaF, the forespore-specific transcription factor, in the trapped region of the chromosome is sufficient to produce spores in the absence of the essential activators SpoIIAA and SpoIIE. We propose that transient genetic asymmetry is the device that releases SpoIIE phosphatase activity in the forespore and establishes cell specificity. (+info)
A genome-wide screen for asthma-associated quantitative trait loci in a mouse model of allergic asthma. (8/6287)Asthma is the most common illness of childhood, affecting one child in seven in the UK. Asthma has a genetic basis, but genetic studies of asthma in humans are confounded by uncontrolled environmental factors, varying penetrance and phenotypic pleiotropy. An animal model of asthma would offer controlled exposure, limited and consistent genetic variation, and unlimited size of sibships. Following immunization and subsequent challenge with ovalbumin, the Biozzi BP2 mouse shows features of asthma, including airway inflammation, eosinophil infiltration and non-specific bronchial responsiveness. In order to identify genetic loci influencing these traits, a cross was made between BP2 and BALB/c mice, and a genome-wide screen carried out in the F2progeny of the F1intercross. Five potentially linked loci were identified, four of which corresponded to human regions of syntenic homology that previously have shown linkage to asthma-associated traits. (+info)
Karyotype evolution and flexible (conventional versus inverted) meiosis in insects with holocentric chromosomes: a case study...
TY - JOUR. T1 - Karyotype evolution and flexible (conventional versus inverted) meiosis in insects with holocentric chromosomes: a case study based on Polyommatus butterflies. AU - Lukhtanov, Vladimir A. AU - Dantchenko, Alexander V. AU - Khakimov, Fayzali R. AU - Sharafutdinov, Damir AU - Pazhenkova, Elena A. PY - 2020/7/7. Y1 - 2020/7/7. N2 - The Polyommatus butterflies have holocentric chromosomes, which are characterized by kinetic activity distributed along the entire chromosome length, and the highest range of haploid chromosome numbers (n) known within a single eukaryotic genus (from n = 10 to n = 226). Previous analyses have shown that these numbers most likely evolved gradually from an ancestral karyotype, in accordance with the Brownian motion model of chromosome change accumulation. Here we studied chromosome sets within a monophyletic group of previously non-karyotyped Polyommatus species. We demonstrate that these species have a limited interspecific chromosome number variation from ...
Analysis of Chriz involved in Drosophila polytene chromosome structuring and binding
Drosophila polytene chromosomes are compacted into a series of bands and interbands. Z4 is a protein to keep this pattern, since Z4 mutant larvae show a decompaction of chromosomes and a loss of banding pattern (Eggert et al., 2004). By coimmuno-precipitation, we identified a chromodomain protein, which we named Chriz, for chromodomain protein interacting with Z4 (Gortchakov et al., 2005). In my PhD thesis, I tested the interactions between the full length proteins and different fragments of Chriz and Z4 which showed that Chriz could directly interact with Z4 in vivo. The interaction domains were mapped and it was determined that the N terminus of Z4 and the C terminus of Chriz are sufficient for mutual interaction. GST pull down confirmed these data and more precisely localized the interaction domains. Chriz, like Z4, is present in many interbands of interphase polytene chromosomes. The overexpression of different domains of Chriz demonstrated that both the N and C terminus are sufficient for ...
Immunological method for mapping genes on Drosophila polytene chromosomes | PNAS
A method is described for localizing DNA sequences hybridized in situ to Drosophila polytene chromosomes. This procedure utilizes a biotin-labeled analog of TTP that can be incorporated enzymatically into DNA probes by nick-translation. After hybridization in situ, the biotin molecules in the probe serve as antigens which bind affinity-purified rabbit antibiotin antibodies. The site of hybridization is then detected either fluorimetrically, by using fluorescein-labeled goat anti-rabbit IgG, or cytochemically, by using an anti-rabbit IgG antibody conjugated to horseradish peroxidase. When combined with Giemsa staining, the immunoperoxidase detection method provides a permanent record that is suitable for detailed cytogenetic analysis. This immunological approach offers four advantages over conventional autoradiographic procedures for detecting in situ hybrids: (i) the time required to determine the site of hybridization is decreased markedly, (ii) biotin-labeled probes are chemically stable and ...
Conditional Mutations in the Mitotic Chromosome Binding Function of the Bovine Papillomavirus Type 1 E2 Protein | Journal of...
To study the interaction of E2 with specific regions of the mitotic chromosome in more detail, we developed a method to spread the mitotic chromosomes in situ that was compatible with indirect immunofluorescence for the E2 protein. This method was adapted from that of Smith et al., who used it to localize tankyrase on human telomeres (27). This technique resulted in well-spread mitotic chromosomes and demonstrated that the wild-type E2-TA was localized on individual chromosomes as speckles, whereas E2-TR was excluded from chromosomes. This technique disrupted the perichromosomally associated proteins Ki67 and topoisomerase II but did not affect the chromosomal association of phosphorylated histone H3 (data not shown). This indicates that the E2 protein is tightly bound to mitotic chromosomes. In fact, in other studies from our laboratory we find that E2-TA forms a very stable complex with mitotic chromosomes that is resistant to high salt (M. McPhillips, K. Ozato, and A. A. McBride, submitted ...
OSA | Technique of laser chromosome welding for chromosome repair and artificial chromosome creation
Here we report a technique of laser chromosome welding that uses a violet pulse laser micro-beam for welding. The technique can integrate any size of a desired chromosome fragment into recipient chromosomes by combining with other techniques of laser chromosome manipulation such as chromosome cutting, moving, and stretching. We demonstrated that our method could perform chromosomal modifications with high precision, speed and ease of use in the absence of restriction enzymes, DNA ligases and DNA polymerases. Unlike the conventional methods such as de novo artificial chromosome synthesis, our method has no limitation on the size of the inserted chromosome fragment. The inserted DNA size can be precisely defined and the processed chromosome can retain its intrinsic structure and integrity. Therefore, our technique provides a high quality alternative approach to directed genetic recombination, and can be used for chromosomal repair, removal of defects and artificial chromosome creation. The ...
PLOS Genetics: Heterochromatic Threads Connect Oscillating Chromosomes during Prometaphase I in Drosophila Oocytes
Author Summary Proper chromosome segregation is essential during the production of eggs and sperm. Chromosome missegregation during meiosis results in the lethality of the offspring or in children carrying extra copies of a given chromosome (for example, Down syndrome). Recombination results in homologous chromosomes becoming physically interlocked in a manner that is normally sufficient to ensure proper segregation. Chromosomes that fail to undergo recombination require additional mechanisms to ensure their proper segregation. In Drosophila melanogaster oocytes we show that chromosomes that fail to recombine undergo dynamic movements on the meiotic spindle prior to their proper segregation. Although previous studies had shown that non-recombinant chromosomes move to opposite sides of the developing meiotic spindle, we show that these chromosomes can cross the spindle and re-associate with their homologs to attempt reorientation. Additionally, we observed threads connecting separated non-recombinant
Aurora B controls the association of condensin I but not condensin II with mitotic chromosomes | Journal of Cell Science
In mitosis and meiosis, the structure of eukaryotic chromosomes changes dramatically. In interphase, chromosomes occupy relatively large territories in which individual sister chromatids cannot be distinguished (Bolzer et al., 2005; Cremer et al., 2006). In prophase, the volume that is occupied by chromosomes becomes much smaller, chromosomes can thus be observed as individual elongated structures, and sister chromatids are partially resolved from each other in chromosome arm regions (Swedlow and Hirano, 2003). These morphological changes are believed to facilitate the attachments of chromosomes to the mitotic or meiotic spindle and the separation of chromosomes or sister chromatids in anaphase.. The morphological changes of chromosomes in early mitosis and meiosis are caused at least in part by changes in chromosomal protein composition and in the post-translational modification of chromosomal proteins. In mitotic Xenopus egg extracts, both phosphorylation of the linker histone H1 (Maresca et ...
Smc5/6 Coordinates Formation and Resolution of Joint Molecules with Chromosome Morphology to Ensure Meiotic Divisions
Author Summary Meiosis is a specialized cell division that exactly halves the number of chromosomes transmitted from each parent to their offspring via gamete cells (such as sperm and eggs). This requires that matching (homologous) chromosomes associate and then separate into different cells such that each gamete contains exactly one complete set of chromosomes. In many organisms, this sequence of events is facilitated by the induction and repair of chromosome breaks via a process called homologous recombination. As homologous chromosomes engage in recombination, matching DNA strands between broken and intact template chromosomes become intertwined in repair intermediates called Joint Molecules. In this study, we show that a highly conserved protein complex called the Structural Maintenance of Chromosomes 5/6 (Smc5/6) complex is important for regulating the choice of recombination template as well as for the resolution of Joint Molecules that is required for chromosomes to separate. Even though Joint
An alternative approach for the induction of premature chromosome condensation in human peripheral blood lymphocytes using...
|span||b|Purpose:|/b| The premature chromosome condensation (PCC) technique is used to study exposure to external radiation through the determination of chromosome fragments observed in interphase cells. The presence of large telomeric signals in CHO cells interferes with the detection of PCC fragments an|/span| …
Duplicating chromosomes once each cell cycle produces sister chromatid pairs which - GLO1 inhibitors for neuropsychiatric
Duplicating chromosomes once each cell cycle produces sister chromatid pairs which separate accurately at anaphase. polytene chromosomes can also separate prior to metaphase through a spindle-independent mechanism termed Separation-Into-Recent-Sisters (SIRS). Both reduplication responses require the spindle assembly checkpoint protein Mad2. While Mad2 delays anaphase separation of metaphase polytene chromosomes Mad2s control of overall mitotic timing ensures efficient SIRS. Our results pinpoint mechanisms enabling continued proliferation after genome reduplication a finding with implications for cancer progression and prevention. DOI: http://dx.doi.org/10.7554/eLife.15204.001 species of fruit fly Stormo and Fox discovered two distinct ways in AR-231453 which cells respond to extra chromosome duplications. One response occurs in cells that were experimentally engineered to undergo an extra chromosome duplication. These cells delay division so that the chromosome separation machinery can somehow ...
Education - Chromosomes - History
Original text and figures were provided by N. Kurata). Chromosome number of cultivated rice was reported as 2n=24 by Kuwada in 1910. Until 1930 this number was confirmed by the observation of rice chromosomes at meiosis. However, due to the extreme smallness, the morphology and structure of rice chromosomes remained unclear and no karyotype analysis was reported until the1970s. Only some attempts of morphological identification based on the figures at pachytene stage in meiosis were reported in this period.. In 1978, Kurata and Omura (1978) invented a new method of chromosome preparation technique, with which karyotype analysis on rice chromosomes was first conducted and identification of all twelve chromosomes became realized. Furthermore, all extra chromosomes of 12 trisomics series of rice (2n=24+1) were identified with this method by Kurata et al. (1981) and Iwata et al. (1984) so that the relationship between the linkage group based on the genes and the chromosomes on which the genes were ...
Section D - Prokaryotic and Eukaryotic Chromosome Structure - ppt video online download
Contents D1 Prokaryotic chromosome structure D2 Chromatin Structure The Escherichia. coli chromosome, DNA domains, Supercoling of the genome, DNA-binding proteins D2 Chromatin Structure Chromatin, Histones, Nucleosomes, The role of H1, Linker DNA, The 30 nm fiber, Highter order structure D3 Eukaryotic Chromosomal Structure The mitotic chromosome, The centromere, Telomeres, Interphase chromosome, Heterochromatin, Euchromatin, DNase Ⅰ hypersensitivity, CpG methylation, Histone variants and modification D4 Genome complexity Noncoding DNA, Reasociation Kinetics, Unique sequence DNA, Tandem gene clusters, Dispersed repetitive DNA, Satellite DNA, Genetic polymorphism D5 The flow of genetic information The central dogma, Prokaryotic gene expression, Eukaryotic gene expression
Simply put, chromosomes are the structures that hold our genes. Genes are the individual instructions that tell our bodies how to develop and keep our bodies running healthy. In every cell of our body there are 20,000 to 25,000* genes that are located on 46 chromosomes. These 46 chromosomes occur as 23 pairs. We get one of each pair from our mother in the egg, and one of each pair from our father in the sperm. The first 22 pairs are labeled longest to shortest. The last pair are called the sex chromosomes labeled X or Y. Females have two X chromosomes (XX), and males have an X and a Y chromosome (XY). Therefore everyone should have 46 chromosomes in every cell of their body. If a chromosome or piece of a chromosome is missing or duplicated, there are missing or extra genes respectively. When a person has missing or extra information (genes) problems can develop for that individuals health and development. Each chromosomes has a p and q arm; p (petit) is the short arm and q (next letter in the ...
chromosome - Ask the Atheist
Its a good question because a sudden whole extra chromosome full of junk, or a whole one gone missing, can indeed cause serious defects. That said, it helps to remember that a chromosome is merely a container of genes, and the number of chromosomes has very little to do with the amount of genetic information in each.. The addition of a chromosome is the more complex process, so Im linking to an explanation of one mechanism by PZ Myers. Essentially, one chromosomes worth of genes ends up being shared by two, and at first it can interact just fine with the old combined chromosome because the total sequence is the same. This does introduce a higher rate of error until individuals with the split chromosome start mating with each other, at which point theres no longer a downside. Once the new number of chromosomes is settled, each chromosome is free to mutate independently and add new genetic information in the usual ways.. As for a reduction in chromosomes, we need look no further than our own ...
Chromosome Analysis - The leading Health & Diagnostic provider for DNA, Genetic Tests & Cancer Screening in Dubai, UAE
Everyone has 23 pairs of chromosomes, 22 pairs of autosomes and one pair of sex chromosomes. The science that relates to the study of these chromosomes is referred to as Cytogenetics. Our tests that we offer, analyzes the whole chromosome and identifies any disorders present.. Why do a Cytogenic Test?. There are many disorders that can be diagnosed by examining a persons whole chromosome.. Chromosome abnormalities constitute a major category of medical genetic disorders. In a clinical setting, chromosome abnormalities account for a large proportion of cases involving individuals referred with congenital malformations, developmental delay, mental retardation, or infertility; women with gonadal dysgenesis; spontaneous abortions, and couples with repeated spontaneous miscarriages.. Cytogenetic laboratories provide microscopic studies of human chromosomes in order to diagnose abnormalities in prenatal/postnatal and cancer specimens. The studies involve analyzing chromosomes found in blood, bone ...
Chromosomes, DNA and Genes: Tiny Things That Have a Huge Effect on Who We Are! - Windows to the Universe
Do you look a bit like your brothers and sisters? Do you look a bit like your parents? The similarities are because, unless you were adopted, you and the other members of your family have genetic material in common.. Some characteristics, or traits, result from interactions with the environment, others are determined from the genetic material in your chromosomes. Chromosomes are the keepers of the genetic material in eukaryotic cells. An organism has the same chromosomes for its entire life. The chromosomes are located within each cell nucleus. They provide the directions for how the cell is supposed to function and determine some characteristics about how the individual looks. Each chromosome contains a very complex molecule called DNA. The DNA molecule contains genes, which direct how an organisms body is built and maintained.. Heredity is the passage of DNA from the chromosomes of one generation to the chromosomes of the next. Chromosomes in your body are in pairs. One chromosome of each ...
Chromosome Dynamics - DK Chromosome Dynamics
DNA must allow for various processing events; it is transcribed into RNA to make the stored information available to the cell; it is replicated and identical copies of itself are equally distributed to its daughter cells; it is frequently repaired, when damaged by endogenous or exogenous sources. All these processes, whether concerning condensed or uncondensed, mitotic or meiotic chromosomes, make them highly flexible and dynamic structures, which change their nucleotide composition as well as their morphology and position.. Regions on chromosomes that undergo replication or repair are transported to the respective centers of activity, replication factories and repair centers. Likewise, interphase chromosomes or parts thereof shuttle between internal transcriptionally active nuclear domains and the nuclear periphery, depending on their transcriptional activity in certain developmental stages or tissues. The most dramatic chromosome movements occur during mitosis and meiosis when daughter ...
Chromosome Dynamics - DK Chromosome Dynamics
DNA must allow for various processing events; it is transcribed into RNA to make the stored information available to the cell; it is replicated and identical copies of itself are equally distributed to its daughter cells; it is frequently repaired, when damaged by endogenous or exogenous sources. All these processes, whether concerning condensed or uncondensed, mitotic or meiotic chromosomes, make them highly flexible and dynamic structures, which change their nucleotide composition as well as their morphology and position.. Regions on chromosomes that undergo replication or repair are transported to the respective centers of activity, replication factories and repair centers. Likewise, interphase chromosomes or parts thereof shuttle between internal transcriptionally active nuclear domains and the nuclear periphery, depending on their transcriptional activity in certain developmental stages or tissues. The most dramatic chromosome movements occur during mitosis and meiosis when daughter ...
Human Genetic Material (GEN) - Ergopathics
Kit Contents: Chromosome 1, Chromosome 2, Chromosome 3, Chromosome 4, Chromosome 5, Chromosome 6, Chromosome 7, Chromosome 8, Chromosome 9, Chromosome 10, Chromosome 11, Chromosome 12, Chromosome 13, Chromosome 14, Chromosome 15, Chromosome 16, Chromosome 17, Chromosome 18, Chromosome 19, Chromosome 20, Chromosome 21,
Automated discrimination of dicentric and monocentric chromosomes by m by Yanxin Li, Joan H. Knoll et al.
© 2016 Wiley Periodicals, Inc. Dose from radiation exposure can be estimated from dicentric chromosome (DC) frequencies in metaphase cells of peripheral blood lymphocytes. We automated DC detection by extracting features in Giemsa-stained metaphase chromosome images and classifying objects by machine learning (ML). DC detection involves (i) intensity thresholded segmentation of metaphase objects, (ii) chromosome separation by watershed transformation and elimination of inseparable chromosome clusters, fragments and staining debris using a morphological decision tree filter, (iii) determination of chromosome width and centreline, (iv) derivation of centromere candidates, and (v) distinction of DCs from monocentric chromosomes (MC) by ML. Centromere candidates are inferred from 14 image features input to a Support Vector Machine (SVM). Sixteen features derived from these candidates are then supplied to a Boosting classifier and a second SVM which determines whether a chromosome is either a DC or MC. The
A new chromosome region possibly derived from double minutes in an in vitro transformed epithelial cell line<...
TY - JOUR. T1 - A new chromosome region possibly derived from double minutes in an in vitro transformed epithelial cell line. AU - Cowell, J. K.. PY - 1980. Y1 - 1980. N2 - Double minute chromosomes (DMs) are reported for the first time in in vitro transformed mouse epithelial cells. In one cell line, CSG 122/17, DMs persisted through numerous passages. A subpopulation appeared in this line at passage 23, in which the DMs had disappeared but were replaced by a finely banded chromosome region possibly associated with the distal end of chromosome 5. In a second cell line, CSG 120/7, there was no evidence of DMs in the earliest frozen stock available. However, a finely banded region similar to that found in CSG 122/17 was present and was again associated with chromosome 5, in this case with the proximal end. The possible evolution of these new chromosome regions from DMs is discussed.. AB - Double minute chromosomes (DMs) are reported for the first time in in vitro transformed mouse epithelial ...
In vivo dissection of the chromosome condensation machinery | JCB
Two simple models can be envisaged: either cohesins are needed to activate condensin function or, alternatively, cohesins are required to ensure correct chromosome folding by condensins. These models can be distinguished by following the state of the mitotic chromosomes after a loss of cohesin activity. In the first scenario, the chromosomes remain in an interphase state, and thus would condense upon the readdition of cohesin and the subsequent activation of condensin. In contrast, the latter scenario predicts that misfolded chromosomes would result from the inappropriate action of condensin, and these would likely prove refractory to refolding. To test this, we asked whether chromosome condensation is reversible in the cohesin mutant mcd1-1. In contrast to both the brn1-9 and ycg1-2 condensin mutants, the condensation defect in the mcd1-1 strain was not reversible (Fig. 7 B). One trivial explanation is that no new functional Mcd1-1p protein is made after the shift to the permissive ...
The Shumways: Whats up with those Chromosomes
The sex of a human baby is determined by the composition of its sex chromosomes (a single distinct pair among humans 23 pairs of chromosomes). Females possess two copies of the same chromosome (referred to as the X chromosome); males have one copy of the X chromosome and one copy of the smaller, hook-shaped Y chromosome.. When fertilization occurs, the new gamete (the initial cell from which a fetus grows) always inherits one of the mothers X chromosomes, and either an X or a Y from the father, depending on which chromosome the fertilizing sperm cell happened to inherit. One could say, then, that the father-or, at least, his sperm-determines the sex of the child. On the other hand, the first sperm to reach the egg isnt necessarily the one that fertilizes it; human eggs are rather choosy about that sort of thing. So, in an indirect way, the maternal parent also has some influence on the sex of the child.. Thanks, infoplease.com. Thanks for NOTHING ...
Recombination in the B chromosome of maize to produce A-B-A chromosomes. | Genetics
The translocations between the supernumerary B chromosomes and the normal A chromosomes of maize provide a valuable tool for gene localizations, dosage studies and characterization of mutants as null, leaky or gain-of-function. A procedure is described, that relies on recombination in the B chromosome, for marking each of the various B-A translocations with a single dominant marker that will allow dosage classifications of individuals at the mature kernel stage. This marker is R-scm3, which conditions anthocyanin pigment in the aleurone of the endosperm and the scutellum of the embryo. A test for recombination in the B chromosome was conducted by crossing together two translocations, that were broken on opposite sides of the B centromere, and in different A chromosome arms, namely TB-1La and TB-10L18. An example was recovered that linked genetic markers on 1L and 10L to the B centromere. Cytological examination at pachytene of meiosis confirmed the new chromosomal linkage. The use of this ...
Chromosome Analysis Protocols by John R. Gosden - RUBBERPIXY.COM Book Archive
Left: a metaphase plate. Scale bar =lO pm. Right: a single chromosome from the same metaphase. Scale bar = 1 pm. been possible to combine in situ hybridization with high-quality morphological preservation. As well as providing alternative approaches to chromosome morphology, the methods using cytocentrifuge preparation and isolated chromosomes have the advantage of using little or no fixation prior to the osmium impregnation procedure. They are, therefore, well suited to the study of chromosomal antigens that might be destroyed or extracted by methanol-acetic acid fixation (Fig. Ethidium Bromtde Technique (Originally Described by Ikeuchi [2U. 1. When mamtammg cells for making chromosomes by this method, the cells are kept m a semiconfluent state and only split when the flask is fully confluent (stationary phase). This will give a very crude but reasonably effective means of synchronizing rapidly growing cells. However, the chromosomes are in a more nearly native state after this. 2. Seventeen ...
Digestion-ligation-only Hi-C is an efficient and cost-effective method for chromosome conformation capture | Nature Genetics
Chromosome conformation capture (3C) technologies can be used to investigate 3D genomic structures. However, high background noise, high costs, and a lack of straightforward noise evaluation in current methods impede the advancement of 3D genomic research. Here we developed a simple digestion-ligation-only Hi-C (DLO Hi-C) technology to explore the 3D landscape of the genome. This method requires only two rounds of digestion and ligation, without the need for biotin labeling and pulldown. Non-ligated DNA was efficiently removed in a cost-effective step by purifying specific linker-ligated DNA fragments. Notably, random ligation could be quickly evaluated in an early quality-control step before sequencing. Moreover, an in situ version of DLO Hi-C using a four-cutter restriction enzyme has been developed. We applied DLO Hi-C to delineate the genomic architecture of THP-1 and K562 cells and uncovered chromosomal translocations. This technology may facilitate investigation of genomic organization, gene
Circular Chromosome Conformation Capture (4C) Uncovers Extensive Networks of Epigenetically Regulated Intra- And...
Accumulating evidence converges on the possibility that chromosomes interact with each other to regulate transcription in trans. To systematically explore the epigenetic dimension of such interactions, we devised a strategy termed circular chromosome conformation capture (4C). This approach involves …
Synthetic Yeast Chromosome Manipulation - Singer Instruments
Wild type S. cerevisiae contains 16 chromosomes, each with a distinct set of genes, a centromere and a telomere at each end. How this species came to have 16 chromosomes is a question not fully understood. For example, we know some of our closest ancestors in primates have 24 pairs of chromosomes, yet we only have 23 pairs. This is due to an ancestral fusion in what we now know as Chromosome 23. The number of chromosomes that a species has is unlikely to be chance, and more likely to be a product of an evolutionary advantage, but what happens if a species had less chromosomes?. Two groups simultaneously investigated what would happen to S. cerevisiae if they reduced the number of chromosomes, without removing any essential genes. The two groups; from Institute for Systems Genetics, NYU Langone Health, USA, and Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, China both published their results in Nature on August 1st 2018. Both groups simultaneously worked on ...
Hrb27C, Sqd and Otu cooperatively regulate gurken RNA localization and mediate nurse cell chromosome dispersion in Drosophila...
Nurse cell chromosomes that fail to disperse are also observed in certain alleles of ovarian tumor (otu) (King et al., 1981; King and Storto, 1988; Heino, 1989; Malceva and Zhimulev, 1993; Heino, 1994; Malceva et al., 1995). otu produces two protein isoforms, Otu98 and Otu104, by alternative splicing of a 126 bp exon. Genetic and molecular analyses reveal distinct requirements for each isoform during oogenesis (Storto and King, 1988; Steinhauer and Kalfayan, 1992; Sass et al., 1995; Tirronen et al., 1995). In particular, a mutant that specifically disrupts the Otu104 product has persistent polytene nurse cell chromosomes, suggesting that the 98 kDa Otu isoform is not capable of mediating wild-type chromosome dispersion (Steinhauer and Kalfayan, 1992). This phenotype was also described for mutants in half pint (hfp; pUf68 - FlyBase). Hfp encodes a polyU-binding factor and plays an important role in the alternative splicing of otu. In hfp mutants, there is a dramatic decrease in the levels of ...
Inheritance: Parallelism between Genes and Chromosomes in Inheritance
ii) A trait is represented by only one Mendelian factor inside a gamete. A gamete similarly contains a single chromosome out of a pair of homologous chromosomes due to meiosis that occurs before the formation of gametes.. (iii) An organism has a specific number of chromosomes. The somatic cells are generally diploid having chromosomes in pairs called homologous pairs. The two chromosomes of each homologous pair resemble each other in their morphology and genetic content. They are derived from the two parents through their gametes. It also contains two Mendelian factors for each character. The factors come from different parents through their gametes.. (iv) Each chromosome replicates during S-phase. It comes to have two sister chromatids. The two chromatids separate and pass into two daughter nuclei and cells during mitosis. Similarly, each allelic pair replicates, with one pair passing into each daughter cell during mitosis. This maintains the similar genetic composition of all the cells of a ...
Holocentric chromosome Archives - PacBio
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How chromosomes shrink to fit | Journal of Cell Biology | Rockefeller University Press
Like someone whos moved from a house to an apartment, cells in an early embryo run into space limitations. The embryo remains the same size for its first few divisions, so the cells have to become much smaller, shrinking by as much as 99%. Some components, such as individual mitochondria and clathrin-coated vesicles, seemingly remain the same size as cells miniaturize. But the centrosome, mitotic spindle, and nucleus contract. For more than a century researchers have known that cells in early embryos also compact their chromosomes. To prevent tangling during mitosis, the biggest chromosomes cant exceed half the length of the mitotic spindle (2). However, researchers didnt know which cues cells rely on to determine chromosome size. One research group addressed the question by allowing small nuclei to stew in extracts from large cells for an entire cell cycle (3). The nuclei expanded, suggesting that chromosome size tracks cell size. Another group concluded that chromosome size tracks nuclear ...
Why is the number of chromosomes an organisms has an even number? | Socratic
The reason why the majority of organisms have an even number of chromosomes is because chromosomes are in pairs. A human, for instance, will have half its chromosomes from the father, and half from its mother. There are exceptions to the rule. For instance, an individual with Down Syndrome will have 47 chromosomes instead of 46, because they have trisomy 21 (three copies of the 21st chromosome, instead of just two). Another exception would be polyploidy , which occurs when organisms have more pairs of chromosomes than a diploid cell does. Below is a picture to help visualize polyploidy. An example of a haploid cell would be a gamete (a sperm cell, for instance), and a diploid cell would be a skin cell of a person with 46 chromosomes.
Translocation dicentric chromosomes in prostaglandin E2 induced abortuses and possible aneusomy through asynchronous...
Translocations of a whole chromosome or a chromosome arm have been reported in both normal and abnormal liveborns. Often the abnormal phenotypes could not be explained by the genetic defects of the specific chromosome findings. Warburton et al. described an autosomal anomaly, tdic(12;14), showing gonadal dysgenesis; Pallister et al. described a patient with multiple congenital anomalies and mental retardation who had a normal karyotype in her fibroblasts. The whole chromosome translocation (6;19) was found in her lymphocytes only. Various genetic explanations have been proposed, including undetected lesions, position effects, mutations at the sites of breakage and union, and aneusomy by recombination. Perhaps the whole chromosome translocation per se were not responsible for the malformations, since they were not necessarily found in cells of the deformed organs, or if they were, the abnomalities were not always explained by aberrations of the specific chromsomes involved in the ...
genetics - What are homologous chromosomes? - Biology Stack Exchange
Part of the problem is that chromosome is a slippery word. Really it should refer to a single DNA molecule, but since chromosomes came before DNA this sometimes gets a little loose.. This explanation refers to the five Figures in your question as 1-5 from the top.. Figure 1 A pair of homologous chromosomes from a diploid cell drawn to illustrate their relationship in terms of genes, alleles, centromeres etc. This doesnt really correspond to any biological event. Colour coding is to emphasise that they originated from different parents. I suppose this is what you see in a karyotype.. Figure 2 An homologous pair again, different colours again, but they arent closely side by side. When each one replicates we end up with pairs of sister chromatids joined at the centromere. These are four homologous chromosomes. At mitosis each of the pairs of sister chromatids will be pulled apart with one chromosome going to each daughter cell. So the daughter cell will end up with a pair of homologous ...
chromosome spread | English to German | Genetics
Comparison of affected and unaffected individuals generally involves first looking for structural alterations in the chromosomes, such as deletions or translocations that are visible from chromosome spreads or detectable using PCR based on that DNA sequence. ...
Genetics & Dysmorphology | CURRENT Diagnosis & Treatment Pediatrics, 23e | AccessPediatrics | McGraw-Hill Medical
Human chromosomes consist of DNA (the blueprint of genetic material), specific proteins forming the backbone of the chromosome (called histones), and other chromatin structural and interactive proteins. Chromosomes contain most of the genetic information necessary for growth and differentiation. The nuclei of all normal human cells, with the exception of gametes, contain 46 chromosomes, consisting of 23 pairs (Figure 37-1). Of these, 22 pairs are called autosomes. They are numbered according to their size; chromosome 1 is the largest and chromosome 22 the smallest. In addition, there are two sex chromosomes: two X chromosomes in females and one X and one Y chromosome in males. The two members of a chromosome pair are called homologous chromosomes. One homolog of each chromosome pair is maternal in origin (from the egg); the second is paternal (from the sperm). The egg and sperm each contain 23 chromosomes (haploid cells). During formation of the zygote, they fuse into a cell with 46 chromosomes ...
Variation in Chromosome Structure
Chromosomes can undergo several types of changes which fall into two classes. The first type of change involves changes in chromosome number and is referred to as aneuploidy and euploidy. How these type of changes can occur and their subsequent effect on phenotype will be discussed in the next section. The chromosomal changes that we will discuss now alter the linear order of the chromosome and occur because of deletions, duplications, inversions, translocations and insertions of chromosomal DNA.. The analysis of these types of changes to a large part has been performed in genetic stocks of the fruit fly, Drosophila melanogaster. The chromosomes of this species that are of particular interest, are those found in the salivary glands of larvae. These tissues grow not by cell division but by enlargement. During this enlargement the chromosomes also undergo replication. But this replication is different than in other tissues because:. ...
First 3D Pictures Of Chromosome Structure Revealed - Redorbit
Biotechnology and Biological Sciences Research Council. A new method for visualizing chromosomes is painting a truer picture of their shape, which is rarely like the X-shaped blob of DNA most of us are familiar with.. Scientists at the BBSRC-funded Babraham Institute, working with the University of Cambridge and the Weizmann Institute, have produced beautiful 3D models that more accurately show their complex shape and the way DNA within them folds up.. The X-shape, often used to describe chromosomes, is only a snapshot of their complexity.. Dr Peter Fraser of the Babraham Institute explains: The image of a chromosome, an X-shaped blob of DNA, is familiar to many but this microscopic portrait of a chromosome actually shows a structure that occurs only transiently in cells - at a point when they are just about to divide.. The vast majority of cells in an organism have finished dividing and their chromosomes dont look anything like the X-shape. Chromosomes in these cells exist in a very ...
Chromosome arm legal definition of chromosome arm
Definition of chromosome arm in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is chromosome arm? Meaning of chromosome arm as a legal term. What does chromosome arm mean in law?
Shape Transitions and Chiral Symmetry Breaking in the Energy Landscape of the Mitotic Chromosome
We derive an unbiased information theoretic energy landscape for chromosomes at metaphase using a maximum entropy approach that accurately reproduces the details of the experimentally measured pairwise contact probabilities between genomic loci. Dynamical simulations using this landscape lead to cylindrical, helically twisted structures reflecting liquid crystalline order. These structures are similar to those arising from a generic ideal homogenized chromosome energy landscape. The helical twist can be either right or left handed so chiral symmetry is broken spontaneously. The ideal chromosome landscape when augmented by interactions like those leading to topologically associating domain formation in the interphase chromosome reproduces these behaviors. The phase diagram of this landscape shows that the helical fiber order and the cylindrical shape persist at temperatures above the onset of chiral symmetry breaking, which is limited by the topologically associating domain interaction strength ...
DNA, RNA and Chromosomes - Gene - histology illustration
A chromosome is composed of a very long molecule of DNA and associated proteins that carry hereditary information. The centromere, shown at the center of this chromosome, is a specialized structure that appears during cell division and ensures the correct distribution of duplicated chromosomes to daughter cells. Telomeres are the structures that seal the end of a chromosome. Telomeres play a critical role in chromosome replication and maintenance by counteracting the tendency of the chromosome to otherwise shorten with each round of replication ...
Chromosome Names in genome are incompatible with annotations
Dear community,. while creating an index for the bovine genome with STAR, the process fails because the chromosome names in the annotation file (Bos_taurus.UMD3.1.87.gtf) are incompatible with the ones in the reference file (UMD3.1_chromosomes.fa) (e.g. for chromosome 10 vs gnl,UMD3.1,GK000010.2 Chromosome 10 AC_000167.1, both should be 10).. Apparently, the solution is to change the names in the reference file. Could you suggest a tool that does this for me or a one liner that can transform the names into the chromosome number?. And also, would this affect downstream processing of my results?. I have searched through other threads and couldnt find a better answer than the one given here: Renaming Entries In A Fasta File But it renames chromosomes names in the reference file based on the order they appear.. Cheers!. ...
chromosome Archives - insight | insight
Youd be forgiven for thinking that all chromosomes are X-shaped bundles. But new research MRC-funded research has shown that they spend most of their time looking more like a tangled mass of string, as Peter Fraser, a researcher at the Babraham Institute, explains. The image of a chromosome as an X-shaped blob is familiar to many. But perhaps not everyone knows that this microscopic portrait of a chromosome shows a structure that occurs only transiently in cells, at a point when they are just about to divide by undergoing a process called mitosis.. The vast majority of cells in an organism have finished dividing and their chromosomes dont look anything like the familiar X-shape. Even cells that are still in the business of dividing, such as blood and skin cells, spend most of their time in a kind of resting non-mitotic state. But what do chromosomes in these cells look like?. So far it has been impossible to create accurate pictures of these chromosomes - existing techniques can only ...
New Research Debunks Human Chromosome Fusion | The Institute for Creation Research
Humans and great apes differ in chromosome numbers-humans have 46 while apes have 48. The difference is claimed to be due to the end-to-end fusion of two small, ape-like chromosomes in a human-ape ancestor that joined in the distant past and formed human chromosome 2. This idea was first proposed by researchers who noticed that humans and chimps share similar chromosomal staining patterns when observed under a microscope.1 However, humans and chimps also have regions of their chromosomes that do not share common staining patterns.. Supposed proof for the alleged fusion came in 1991, when researchers discovered a fusion-like DNA sequence about 800 bases in length on human chromosome 2.2 However, it was unexpectedly small in size and extremely degenerate. More importantly, this new fusion-like sequence wasnt what the researchers were expecting to find since it contained a signature never seen before. All known fusions in living animals are associated with a sequence called satellite DNA ...
Human Male Chromosome Spread Next to Cells. Brightfield Photographic Print by Michael Abbey at AllPosters.com
Human Male Chromosome Spread Next to Cells. Brightfield Photographic Print by Michael Abbey - at AllPosters.com. Choose from over 500,000 Posters & Art Prints. Value Framing, Fast Delivery, 100% Satisfaction Guarantee.
Study Links Body Fat, Weight Loss, Chromosome Length in Breast Cancer Patients
Yale Cancer Center researchers have found an explanation about how a healthy diet and exercise are key in cancer prevention and management.
Chromosomes - Stock Video Clip K005/5521 - Science Photo Library
Animation of human chromosomes. Chromosomes are structures containing an organisms DNA genetic material, which form during cell division. DNA usually exists as a long strand in the cells nucleus, and it is replicated in this form. During replication, another copy of the DNA is produced. In preparation for mitotic cell division, the DNA condenses into chromosomes, a tightly-packed form of DNA shaped like an X. The X is formed of the two identical copies of the genetic material left after replication. These are linked by a central region called the centromere. During mitosis, the two halves of the chromosome (chromatids) separate at the centromere, and each half is pulled to opposite sides of the cell. This then divides, giving rise to two identical daughter cells. Humans have 23 pairs of chromosomes, half of each pair from the mother and father. This animation has a transparent background for comping purposes. It is also available on a white background (K005 5520) and a black background (K005 5517). -
Genetics Homeworkkk!!! PLEASE HELP - Biology-Online
Glowing Green Blood Degree 3 is a rare human disorder caused by recessive allele - ggb3. the normal allele is GGB3 dominant. the gene for this disease is located on the human chromosome #1p, a large metacentric chromosome. The sex chromosomes in humans are the X and Y. A man who is a carrier for Glowing Green Blood Degree 3, but does not have the disease himself, inherited his ggb1 allele from his mother. Using the Genotype of this man, and only considering chromosomes #1, X, and Y, draw the correct configuration of chromosomes for Metaphase of Mitosis and one possibility for Metaphase of Meiosis 1. Shade in the paternal chromosomes and label the appropriate chromatid with the correct gene symbol for the Glowing Green Blood Degree 3 allele it carries. Be sure to label each allele and each chromosome. Do not show crossing over in this assignment ...
Chromosome number evolves at equal rates in holocentric and monocentric clades - Ominy Science
by Sarah N. Ruckman, Michelle M. Jonika, Claudio Casola, Heath Blackmon. Despite the fundamental role of centromeres two different types are observed across plants and animals. Monocentric chromosomes possess a single region that function as the centromere while in holocentric chromosomes centromere activity is spread across the entire chromosome. Proper segregation may fail in species with monocentric chromosomes after a fusion or fission, which may lead to chromosomes with no centromere or multiple centromeres. In contrast, species with holocentric chromosomes should still be able to safely segregate chromosomes after fusion or fission. This along with the observation of high chromosome number in some holocentric clades has led to the hypothesis that holocentricity leads to higher rates of chromosome number evolution. To test for differences in rates of chromosome number evolution between these systems, we analyzed data from 4,393 species of insects in a phylogenetic framework. We found that ...
Microdissection of lampbrush chromosomes as an approach for generation of locus-specific FISH-probes and samples for high...
Over the past two decades, chromosome microdissection has been widely used in diagnostics and research enabling analysis of chromosomes and their regions through probe generation and establishing of chromosome- and chromosome region-specific DNA libraries. However, relatively small physical size of mitotic chromosomes limited the use of the conventional chromosome microdissection for investigation of tiny chromosomal regions. In the present study, we developed a workflow for mechanical microdissection of giant transcriptionally active lampbrush chromosomes followed by the preparation of whole-chromosome and locus-specific fluorescent in situ hybridization (FISH)-probes and high-throughput sequencing. In particular, chicken (Gallus g. domesticus) lampbrush chromosome regions as small as single chromomeres, individual lateral loops and marker structures were successfully microdissected. The dissected fragments were mapped with high resolution to target regions of the corresponding lampbrush chromosomes.
Polytene chromosomes - The School of Biomedical Sciences Wiki
Polytene chromosomes, also known as giant chromosomes, are unusual chromosomes. They were discovered to be located in the nuclei of cells in the salivary gland, in third instar larvae, of two-winged (dipteran) flies and other specific tissues in Diptera. These special chromosomes are found in the two-winged (dipteran) fruit fly (Drosophila melonagaster). Polytene chromosomes are formed by the repeated replication of homologous chromosomes, in which the replicated individual sister chromatid strands do not separate. Polytene chromosomes have approximately 1000 identical DNA molecules, which are all perfectly aligned laterally within the structure. Found to be formed in the terminal cells of the larva, these Polytene structures are abnormal chromosomes. These terminal cells are removed when the dipteran move into the next stage of their life cycle: the formation of the pupa. The terminal cells cannot divide and hence, they are eliminated. The polytene chromosomes have been proven very useful ...
Interphase chromosome profiling a method for conventional banded chromosome analysis using interphase nuclei<...
TY - JOUR. T1 - Interphase chromosome profiling a method for conventional banded chromosome analysis using interphase nuclei. AU - Babu, Ramesh. AU - Van Dyke, Daniel L.. AU - Dev, Vaithilingam G.. AU - Koduru, Prasad. AU - Rao, Nagesh. AU - Mitter, Navnit S.. AU - Liu, Mingya. AU - Fuentes, Ernesto. AU - Fuentes, Sarah. AU - Papa, Stephen. PY - 2018/2/1. Y1 - 2018/2/1. N2 - Context.-Chromosome analysis on bone marrow or peripheral blood samples fails in a small proportion of attempts. A method that is more reliable, with similar or better resolution, would be a welcome addition to the armamentarium of the cytogenetics laboratory. Objective.-To develop a method similar to banded metaphase chromosome analysis that relies only on interphase nuclei. Design.-To label multiple targets in an equidistant fashion along the entire length of each chromosome, including landmark subtelomere and centromere regions. Each label so generated by using cloned bacterial artificial chromosome probes is molecularly ...
Premature chromosome condensation as a sign of oocyte immaturity<...
TY - JOUR. T1 - Premature chromosome condensation as a sign of oocyte immaturity. AU - Egozcue Cuixart, Jose. AU - Santalo Pedro, Josep. PY - 1991/1/1. Y1 - 1991/1/1. N2 - In this work we report the possibility that oocyte immaturity is associated with premature chromosome condensation (PCC) after in-vitro fertilization (IVF). Using a murine model, we have related PCC and endoreduplicated-like oocytes to oocyte immaturity as a basis for a prognosis in oocyte immaturity problems. The cytogenetic analysis was performed in 511 embryos obtained from immature oocytes that were directly fertilized in vitro and in 1363 embryos obtained from immature oocytes that were matured in vitro with different concentrations of human chorionic gonadotrophin (HCG) added to the culture medium. As a control we used 507 embryos obtained from freshly ovulated oocytes. PCC at the G1-phase-(G1-PCC) was observed only when immature oocytes were immediately fertilized in vitro (45.4%) and PCC at the S-phase (S-PCC) only ...
Autosomes def the Nanaimo sex two chromosomes are considered in
Feb 10, · Main Difference - Autosomes vs Sex Chromosomes. During the cell division, chromatin in the nucleus shrinks to a thread like structures named chromosomes. Two major types of chromosomes can be found in eukaryotic cells. They are autosomes and sex chromosomes. Humans have 22 homologous pairs of autosomes and one pair of sex chromosomes. Sex chromosome, either of a pair of chromosomes that determine whether an individual is male or female. The sex chromosomes of human beings and other mammals are designated by scientists as X and Y. In humans the sex chromosomes consist of one pair of the total of 23 pairs of chromosomes. The other 22 pairs of chromosomes are called autosomes.. The two sex chromosomes are considered autosomes def in Nanaimo
African Journal of Plant Science - chromosome numbers and karyotype in three species of the genus vernonia schreber in southern...
Detailed cytological studies were carried out on three species of the genus Vernonianamely Vernonia amygdalina (bitter leaf and non-bitter leaf), Vernonia cinerea andVernonia conferta to ascertain their chromosome number. The taxa studied showed diploid number of chromosome for V. cinerea (2n = 18) and V. conferta (2n = 20) and tetraploid number for V. amygdalina (2n = 36). The karyotype show nine (9) pairs of submetacentric chromosomes in V. cinerea and 10 pairs of submetacentric chromosomes in V. conferta. The karyotype of V. amygdalina (bitter leaf) varied from that of V. amygalina (non-bitter) by being larger in size and with a pair of telocentric chromosome. The studies of the pollen fertility suggest that V. amygdalina is an amphidiploid. Key words: Chromosome numbers, karyotype, polyploidy, Vernonia.
Differential expression of a phosphoepitope at the kinetochores of moving chromosomes | JCB
A phosphorylated epitope is differentially expressed at the kinetochores of chromosomes in mitotic cells and may be involved in regulating chromosome movement and cell cycle progression. During prophase and early prometaphase, the phosphoepitope is expressed equally among all the kinetochores. In mid-prometaphase, some chromosomes show strong labeling on both kinetochores; others exhibit weak or no labeling; while in other chromosomes, one kinetochore is intensely labeled while its sister kinetochore is unlabeled. Chromosomes moving toward the metaphase plate express the phosphoepitope strongly on the leading kinetochore but weakly on the trailing kinetochore. This is the first demonstration of a biochemical difference between the two kinetochores of a single chromosome. During metaphase and anaphase, the kinetochores are unlabeled. At metaphase, a single misaligned chromosome can inhibit further progression into anaphase. Misaligned chromosomes express the phosphoepitope strongly on both ...
The roles of long noncoding RNAs in chromosome domains | lncRNA Blog
The cell nucleus is highly organized and functionally compartmentalized. Double-stranded naked DNA is complexed with core histones and assembled into nucleosomes and chromatin, which are surrounded by nuclear domains composed of RNAs and proteins. Recently, three-dimensional views of chromosome organization beyond the level of the nucleosome have been established and are composed of several layers of chromosome domains. Only a small portion of the human genome encodes proteins; the majority is pervasively transcribed into noncoding RNAs whose functions are under intensive investigation. Importantly, the questions of how nuclear retained noncoding RNAs play roles in orchestrating the chromatin structure that have been addressed. The novel noncoding RNA clusters, Eleanors, are derived from a large chromatin domain. They accumulate at the site of their own transcription to form RNA clouds in the nucleus, and they activate gene expression in the chromatin domain. Noncoding RNAs have emerging roles ...
Interchromosomal asynchrony of DNA replication in polytene chromosomes of Drosophila pseudoobscura - Publications of the IAS...
Analysis of 3H-thymidine autoradiograms of late third instar larval salivary glands of Drosophila pseudoobscura revealed a unique example of asynchrony of replication in the autosome complement. The two autosomal arms, 2 and 3, show similar labeling pattern during the initial phases, DD to 3C, and thereafter, the chromosome 3 has fewer labeled sites than chromosome 2 until the most terminal pattern, 1D. Detailed sitewise analysis of 3H-thymidine labeling shows that while nearly 54% of the sites examined in chromosome 2 have a labeling frequency greater than 50%, only 13% of all sites in chromosome 3 have labeling frequency at that range. The number of labeled sites on chromosome 3 plotted against that on chromosome 2 shows a hyperbolic profile rather than a linear relationship. The silver grain ratio of the 2nd to 3rd increases from 1.5 to 3.1 through different stages of the cycle. These results suggest that both chromosomes start replication simultaneously but the third chromosome appears to ...
Chromosome - Simple English Wikipedia, the free encyclopedia
The chromosomes of a cell are in the cell nucleus. They carry the genetic information. Chromosomes are made up of DNA and protein combined as chromatin. Each chromosome contains many genes. Chromosomes come in pairs: one set from the mother; the other set from the father. Cytologists label chromosomes with numbers.. Chromosomes are present in every cell nucleus with very few and special exceptions. This means they are found in all eukaryotes, since only eukaryotes have cell nuclei. When eukaryote cells divide, the chromosomes also divide. When a somatic (body) cell (such as a muscle cell) divides, the process is called mitosis. Before mitosis, the cell copies all the chromosomes and then it can divide. When they duplicate, chromosomes look like the letter X. When they are doubled, the two halves are called chromatids (see diagram). The chromatids are joined at the centromere. There are 46 chromosomes in a human, 23 pairs. Everyone has a set of chromosomes from their father and a matching ...
Chromosome - Simple English Wikipedia, the free encyclopedia
The chromosomes of a cell are in the cell nucleus. They carry the genetic information. Chromosomes are made up of DNA and protein combined as chromatin. Each chromosome contains many genes. Chromosomes come in pairs: one set from the mother; the other set from the father. Cytologists label chromosomes with numbers. Chromosomes are present in every cell nucleus with very few and special exceptions. This means they are found in all eukaryotes, since only eukaryotes have cell nuclei. When eukaryote cells divide, the chromosomes also divide. When a somatic (body) cell (such as a muscle cell) divides, the process is called mitosis. Before mitosis, the cell copies all the chromosomes and then it can divide. When they duplicate, chromosomes look like the letter X. When they are doubled, the two halves are called chromatids (see diagram). The chromatids are joined at the centromere. There are 46 chromosomes in a human, 23 pairs. Everyone has a set of chromosomes from their father and a matching set ...
The Xenopus chromokinesin Xkid is essential for metaphase chromosome alignment and must be degraded to allow anapahase...
The Xenopus chromokinesin Xkid is essential for metaphase chromosome alignment and must be degraded to allow anapahase chromosome movement
Karyological Analyses on the Australian Crayfish Cherax destructor (Decapoda: Parastacidae) » Brill Online
Abstract The karyotype of the Australian crayfish Cherax destructor was studied by examining metaphase chromosome spreads from the testis tissues (TE) and the mitotic cells in division from the regeneration callus of the new forming limb (FL). The sampled tissues showed the same results. A total of 111 mitotic metaphases, 67 TE + 44 FL, were examined and the diploid chromosome number ranged from 179 to 207 per metaphase with a mode at 188, the latter being considered the diploid chromosome number (2n = 188) of the species. The karyotype consisted of 70 metacentric, 42 submetacentric, 48 subtelocentric and 28 telocentric chromosome pairs. The sex chromosomes were cytologically indistinguishable.
CellNetworks - Genetic Control of Chromatin States in Humans Involves Local and Distal Chromosomal Interactions
Deciphering the impact of genetic variants on gene regulation is fundamental to understanding human disease. Although gene regulation often involves long-range interactions, it is unknown to what extent non-coding genetic variants influence distal molecular phenotypes. Here, we integrate chromatin profiling for three histone marks in lymphoblastoid cell lines (LCLs) from 75 sequenced individuals with LCL-specific Hi-C and ChIA-PET-based chromatin contact maps to uncover one of the largest collections of local and distal histone quantitative trait loci (hQTLs). Distal QTLs are enriched within topologically associated domains and exhibit largely concordant variation of chromatin state coordinated by proximal and distal non-coding genetic variants. Histone QTLs are enriched for common variants associated with autoimmune diseases and enable identification of putative target genes of disease-associated variants from genome-wide association studies. These analyses provide insights into how genetic ...
Genetics, Continued Week 10. Meiosis Homologous- each chromosome from the male parent has a corresponding chromosome from the...
Meiosis Meiosis is a process of reduction division in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell. Meiosis is a process of reduction division in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell. Meiosis I- results in two diploid daughter cells, each with the same number of chromosomes as the original cell. Meiosis I- results in two diploid daughter cells, each with the same number of chromosomes as the original cell. Tetrad- structure formed by the pairing of homologous chromosomes Tetrad- structure formed by the pairing of homologous chromosomes Crossing-over- exchanging portions of chromatids while forming tetrads Crossing-over- exchanging portions of chromatids while forming tetrads
chromosome - DNA Methylation, Histone and Chromatin Study
As you can see in the picture, lets see the normal chromosome first, I really dont know what is chromatid in that normal chromosome, does it have two chromatids? the upper one and the lower one? Then lets see the left, replicating chromosome. My teacher said the chromosome replicated and then became two chromosomeS, for an example, 46 chromomes in the nuclear, then they replicate, so now become 92? but in the picture, i think it is still one, you need to think it is as a whole though it consists of two? Are there four chromatids there? upper two and lower two? In the example i gave, so though they replicate, still 46? BTW, how the chromosome replicates? Is that like this )( , two put together, so ) is a chromosome, ( is another chromosome Or two cross to each other, like this X, so \ is a chromosome, / is another chromosome ...
Description of the karyotype of Sphyracephala detrahens (Diptera, Diopsidae)
The eye stalks in Diopsidae (Bilberg, 1820) have been widely examined, but the evolutionary origin of this unique trait remains unclear. Thus, further studies of Sphiracephala (Say, 1828), the extant genus forming a basal branch of Diopsinae, are needed. The present study aimed to identify the karyotype of Sphyracephala detrahens (Walker, 1860) with conventional Giemsa staining. Cytogenetic analysis revealed a diploid number of 2n = 10 including two pairs of metacentric chromosomes, a pair of telocentric chromosomes, a pair of dot-like chromosomes, and a pair of sex chromosomes in S. detrahens. The congener Sphyracephala brevicornis (Say, 1817) has been reported to have the same diploid number, 2n = 10, but different chromosome formula. These results demonstrate that chromosome rearrangements often occur in the genus Sphyracephala.
Chromosome conformation maps in fission yeast reveal cell cycle dependent sub nuclear structure - CSHL Scientific Digital...
Successful progression through the cell cycle requires spatial and temporal regulation of gene transcript levels and the number, positions and condensation levels of chromosomes. Here we present a high resolution survey of genome interactions in Schizosaccharomyces pombe using synchronized cells to investigate cell cycle dependent changes in genome organization and transcription. Cell cycle dependent interactions were captured between and within S. pombe chromosomes. Known features of genome organization (e.g. the clustering of telomeres and retrotransposon long terminal repeats (LTRs)) were observed throughout the cell cycle. There were clear correlations between transcript levels and chromosomal interactions between genes, consistent with a role for interactions in transcriptional regulation at specific stages of the cell cycle. In silico reconstructions of the chromosome organization within the S. pombe nuclei were made by polymer modeling. These models suggest that groups of genes with high ...
DISTRIBUTION OF NONSTRUCTURAL VARIATION BETWEEN WHEAT CULTIVARS ALONG CHROMOSOME ARM 6Bp: EVIDENCE FROM THE LINKAGE MAP AND...
Metaphase I (MI) pairing of homologous chromosomes in wheat intercultivar hybrids (heterohomologous chromosomes) is usually reduced relative to that within the inbred parental cultivars (euhomologous chromosomes). It was proposed elsewhere that this phenomenon is caused by polymorphism in nucleotide sequences (nonstructural chromosome variation) among wheat cultivars. The distribution of this polymorphism along chromosome arm 6Bp (=6BS) of cultivars Chinese Spring and Cheyenne was investigated. A population of potentially recombinant chromosomes derived from crossing over between telosome 6Bp of Chinese Spring and Cheyenne chromosome 6B was developed in the isogenic background of Chinese Spring. The approximate length of the Chinese Spring segment present in each of these chromosomes was assessed by determining for each chromosome the interval in which crossing over occurred (utilizing the rRNA gene region, a distal C-band and the gliadin gene region as markers). The MI pairing frequencies of ...
Gene and Chromosome Mutation Worksheet Beautiful 53 Gene Mutations Worksheet Chromosome Mutation Worksheet - Chessmuseum...
Gene and Chromosome Mutation Worksheet Beautiful 53 Gene Mutations Worksheet Chromosome Mutation Worksheet one of Chessmuseum Template Library - free resume template for word education on a resume example ideas, to explore this Gene and Chromosome Mutation Worksheet Beautiful 53 Gene Mutations Worksheet Chromosome Mutation Worksheet idea you can browse by and . We hope your happy with this Gene and Chromosome Mutation Worksheet Beautiful 53 Gene Mutations Worksheet Chromosome Mutation Worksheet idea. You can download and please share this Gene and Chromosome Mutation Worksheet Beautiful 53 Gene Mutations Worksheet Chromosome Mutation Worksheet ideas to your friends and family via your social media account. Back to 50 Gene and Chromosome Mutation Worksheet. ...
Unable to Extract Variant into VCF File for a Specific Chromosome Position
Oracle Health Sciences Omics Data Bank - Version 3.0.1 and laterUnable to Extract Variant into VCF File for a Specific Chromosome Position
Chromomere - Biology-Online Dictionary
Supplement In genetics, chromomere is one of those beadlike granules arranged in a linear series on the chromosomes of eukaryotes. Chromomeres form from the local coiling of a continuous DNA thread. They become more distinct during prophase of both mitosis and meiosis. In meiosis, they are evident as early as the leptotene phase of prophase I especially because the chromosomes are starting to get condensed at this stage. In the next stage, i.e. zygotene, wherein the homologous chromosomes pair up in pairs, the chromomeres aid the homologous chromosomes to align with each other and form homologous rough pairing. Chromomeres contain genes and the arrangement of chromomere structure may be applied in controlling gene expression. Maps of chromomere structure may be made to be used for genetic as well as for evolutionary studies. They may prove useful in locating genes on a chromosome and in analyzing chromosomal aberrations. In anatomy, chromomere pertains to the central part of a blood platelet. It ...
Gene and Chromosome Mutation Worksheet Beautiful 12 Best Of Gene and Chromosome Mutation Worksheet - Chessmuseum Template...
Gene and Chromosome Mutation Worksheet Beautiful 12 Best Of Gene and Chromosome Mutation Worksheet one of Chessmuseum Template Library - free resume template for word education on a resume example ideas, to explore this Gene and Chromosome Mutation Worksheet Beautiful 12 Best Of Gene and Chromosome Mutation Worksheet idea you can browse by and . We hope your happy with this Gene and Chromosome Mutation Worksheet Beautiful 12 Best Of Gene and Chromosome Mutation Worksheet idea. You can download and please share this Gene and Chromosome Mutation Worksheet Beautiful 12 Best Of Gene and Chromosome Mutation Worksheet ideas to your friends and family via your social media account. Back to 50 Gene and Chromosome Mutation Worksheet. ...
The Role of Dicentric Chromosome Formation and Secondary Centromere Deletion in the Evolution of Myeloid Malignancy
Dicentric chromosomes have been identified as instigators of the genome instability associated with cancer, but this instability is often resolved by one of a number of different secondary events. These include centromere inactivation, inversion, and intercentromeric deletion. Deletion or excision of one of the centromeres may be a significant occurrence in myeloid malignancy and other malignancies but has not previously been widely recognized, and our reports are the first describing centromere deletion in cancer cells. We review what is known about dicentric chromosomes and the mechanisms by which they can undergo stabilization in both constitutional and cancer genomes. The failure to identify centromere deletion in cancer cells until recently can be partly explained by the standard approaches to routine diagnostic cancer genome analysis, which do not identify centromeres in the context of chromosome organization. This hitherto hidden group of primary dicentric, secondary monocentric chromosomes,
Chromosome 5, Trisomy 5p - NORD (National Organization for Rare Disorders)
In individuals with trisomy 5p, all or a portion of the short arm (p) of chromosome 5 (5p) appears three times (trisomy) rather than twice in cells of the body. Chromosomes are found in the nucleus of all body cells. They carry the genetic characteristics of each individual. Pairs of human chromosomes are numbered from 1 through 22, with an unequal 23rd pair of X and Y chromosomes for males and two X chromosomes for females. Each chromosome has a short arm designated as p, a long arm identified by the letter q, and a narrowed region at which the two arms are joined (centromere). Chromosomes are further subdivided into bands that are numbered outward from the centromere. For example, the short arm of chromosome 5 includes bands 5p10 (at the centromere or constriction of the chromosome) to 5p15, which is the end of the short arm or terminal band of 5p (also known as 5pter).. The range and severity of associated symptoms and findings may depend on the length and location of the trisomic ...
DNA image-fluorimetry of individual human chromosomes - Semantic Scholar
A microfluorimetric method has been developed for determination of DNA content in individual human chromosomes. The method is based on a preliminary identification of chromosomes with Hoechst 33258 followed by staining of the chromosomes with Feulgen reaction by using Schiffs reagent type ethidium bromide-SO2 and then by measuring the fluorescence intensity of the chromosomes by using an image analyzer. The method allows determining the DNA content of individual chromosomes with an accuracy up to 4.5 fg. The DNA content of individual human chromosomes and their p-and q-arms, as well as homologous chromosomes, were measured by using the developed method. It has been shown that the DNA content in chromosomes of the normal human karyotype is unstable and can fluctuate in some chromosomes within 35-40 fg.
Chromosome Map - Genes and Disease - NCBI Bookshelf
Our genetic information is stored in 23 pairs of chromosomes that vary widely in size and shape. Chromosome 1 is the largest and is over three times bigger than chromosome 22. The 23rd pair of chromosomes are two special chromosomes, X and Y, that determine our sex. Females have a pair of X chromosomes (46, XX), whereas males have one X and one Y chromosomes (46, XY). Chromosomes are made of DNA, and genes are special units of chromosomal DNA. Each chromosome is a very long molecule, so it needs to be wrapped tightly around proteins for efficient packaging.
Algorithm using LSP to find symmetric axes of chromosomes | (2001) | Wang | Publications | Spie
Chromosomes are the primary objects studied in cytogenetics. Recent efforts have been devoted to automating the analysis of banded metaphase chromosomes. Feature extraction is the first step to identify a chromosome. Many useful features, such as the length and the number of bands of a chromosome, can be measured along with the chromosomes longitudinal symmetric axis. Therefore, finding this axis is a necessary precursor to making those measurements. In this paper, a new algorithm for finding a symmetric axis of a chromosome is discussed. The author introduced a concept of local symmetric property of an oblong object, and, then, applied this concept to a chromosome to find the symmetric axis after the boundary of the chromosome has been found. The results of the experiments show that the algorithm works well for both straight and bent chromosomes. Since the algorithms is based on the geometric properties of an object rather than its biological properties, it also can be used to find the ...
Can changes in the number of chromosomes affect health and development? - Genetics Home Reference
Human cells normally contain 23 pairs of chromosomes, for a total of 46 chromosomes in each cell. A change in the number of chromosomes can cause problems with growth, development, and function of the bodys systems. These changes can occur during the formation of reproductive cells (eggs and sperm), in early fetal development, or in any cell after birth. A gain or loss of chromosomes from the normal 46 is called aneuploidy.. A common form of aneuploidy is trisomy, or the presence of an extra chromosome in cells. Tri- is Greek for three; people with trisomy have three copies of a particular chromosome in cells instead of the normal two copies. Down syndrome is an example of a condition caused by trisomy. People with Down syndrome typically have three copies of chromosome 21 in each cell, for a total of 47 chromosomes per cell.. Monosomy, or the loss of one chromosome in cells, is another kind of aneuploidy. Mono- is Greek for one; people with monosomy have one copy of a particular ...
Chromosomes | PeaceHealth
Chromosomes are cell structures made up of genetic material (DNA). They are a part of most types of cells in the body. Humans have 46 chromosomes (23 pairs). Half of a persons chromosomes come from the mother and half from the father. One of the 23 pairs determines a persons gender. The sex chromosomes are called X and Y. For a child to be female, she must inherit an X chromosome from each parent (XX). For a child to be male, he must inherit an X chromosome from his mother and a Y chromosome from his father (XY). The DNA of the chromosomes is divided up into genes. The genes determine the features a person inherits from his or her parents, such as blood type and other characteristics, including risks for developing certain diseases. Changes in chromosomes or genes may cause changes in certain body processes or functions. These changes may be undetectable or may cause genetic diseases, such as hemophilia or Down syndrome. Gene changes can be passed from parents to children or can occur through ...
Two chromosomes human a female male sex and Swan what body for the are Hill in
Apr 17, · In this system, the sex of an individual is determined by a pair of sex chromosomes. Females typically have two of the same kind of sex chromosome (XX), and are called the homogametic sex. Males typically have two different kinds of sex chromosomes (XY), and are called the heterogametic sex. Humans and most other mammals have two sex chromosomes, the X and the Y. Females have two X chromosomes in their cells, while males have both X and a Y chromosomes in their cells. Egg cells all contain an X chromosome, while sperm cells contain an X or Y chromosome. This arrangement means that it is the male that determines the sex of the offspring when fertilization occurs.. What are the two sex chromosomes for a human female and male body in Swan Hill
Chromosomes dance and pair up on the nuclear membrane - Healthcanal.com : Healthcanal.com
To facilitate this pairing, Dernburg has shown, each of the nematodes 12 chromosomes becomes attached by one end to patches on the nuclear membrane that envelops the chromosomes. The patches form a bridge between the chromosomes and the cytoskeleton outside the nucleus. The skeleton assists the random movement of these patches, each with a chromosome attached, around the nuclear membrane, until each chromosome encounters its homolog. Once a chromosome finds its mate and pairs up, the paired homologs remain attached to each other through recombination, separating only prior to segregation.. To many biologists, it seemed likely that synaptonemal complex formation would occur spontaneously between paired chromosomes, Dernburg said. But she and her colleagues have now shown that the cell actively prevents formation of the synaptonemal complex until it has checked and made sure the paired chromosomes are really homologs.. The punch line of our paper is that it indicates there is a check point that ...
Evidence for a relatively random array of human chromosomes on the mitotic ring<...
TY - JOUR. T1 - Evidence for a relatively random array of human chromosomes on the mitotic ring. AU - Allison, David C.. AU - Nestor, Andrea L.. N1 - Copyright: Copyright 2007 Elsevier B.V., All rights reserved.. PY - 1999/4/5. Y1 - 1999/4/5. N2 - We used fluorescence in situ hybridization (FISH) to study the positions of human chromosomes on the mitotic rings of cultured human lymphocytes, MRC- 5 fibroblasts, and CCD-34Lu fibroblasts. The homologous chromosomes of all three cell types had relatively random positions with respect to each other on the mitotic rings of prometaphase rosettes and anaphase cells. Also, the positions of the X and Y chromosomes, colocalized with the somatic homologues in male cells, were highly variable from one mitotic ring to another. Although random chromosomal positions were found in different pairs of CCD- 34Lu and MRC-5 late-anaphases, the separations between the same homologous chromosomes in paired late-anaphase and telophase chromosomal masses were highly ...
Forms of leukemia can be found on six different chromosomes. Acute leukemias can be found on chromosomes 1, 2, and 13, T-Cell developmental leukemia is found on chromosomes 3 and X, and the cause of myelogenous leukemia is in a protein coded for in chromosome 11 at 11p11.9. Chromosome 11 contains 134 million bases. Chromosome 11 has been identified with 151 diseases. Only chromosomes 1, 2, and X contain more currently identified diseases. Chromosome 11 has the most cancerous conditions of all of the chromosomes associated with it ...
Role Of Protein In Distinguishing Chromosome Ends From DNA Breaks - Redorbit
The Stowers Institutes Baumann Lab has demonstrated how human cells protect chromosome ends from misguided repairs that can lead to cancer. The work, published in The EMBO Journal, a publication of the European Molecular Biology Organization, follows the teams 2007 in vitro demonstration of the role of the hRAP1 protein in preventing chromosome ends from being fused to new DNA breaks.. Chromosomes are linear. Their ends (called telomeres) should look like DNA breaks to the proteins that repair them. But somehow, cells are able to distinguish chromosome ends from DNA breaks. In this work, the team demonstrated that the human RAP1 protein plays a key role in preventing chromosome ends from being fused to new DNA breaks. Chromosome end fusions result in genomic instability, which can cause cancer. These findings suggest that RAP1 plays a critical role in cancer prevention in humans.. Protecting naturally occurring chromosome ends from erosion and fusions may increase longevity and reduce cancer ...
chromosome, pericentric region QuickView - Correlation Engine
The region of a chromosome that includes the centromeric DNA and associated proteins. In monocentric chromosomes, this region corresponds to a single area of the chromosome, whereas in holocentric chromosomes, it is evenly distributed along the chromosome…
In sex and between distinguish quizlet chromosomes autosomes Accrington vocabulary
3. Distinguish between autosomes and sex chromosomes, state how many of each are in your diploid cells, and state the sex-chromosome combinations that are in human males and human females. 4. Describe an individuals karyotype. 5. Explain the relationship between genes and chromosomes. 6. Explain the relationship between genes and alleles. 7. Oct 04, · The chromosomes, apart from the sex chromosomes, are known as autosomes of an organism. The number of chromosomes varies from one organism to others. In humans, there is a total of 46 chromosomes or in pair of Out of these, 2 are sex chromosome (XX or XY), and 44 are autosomes.. Distinguish between sex chromosomes and autosomes quizlet vocabulary in Accrington
Flow sorting enrichment and nanopore sequencing of chromosome 1 from a Chinese individual - UAB Digital Repository of Documents
Sorting of individual chromosomes by Flow Cytometry (flow-sorting) is an enrichment method to potentially simplify genome assembly by isolating chromosomes from the context of the genome. We have recently developed a workflow to sequence native, unamplified DNA and applied it to the smallest human chromosome, the Y chromosome. Here, we modify improve upon that workflow to increase DNA recovery from chromosome sorting as well as sequencing yield. We apply it to sequence and assemble the largest human chromosome - chromosome 1 - of a Chinese individual using a single Oxford Nanopore MinION flow cell. We generate a selective and highly continuous assembly whose continuity reaches into the order of magnitude of the human reference GRCh38. We then use this assembly to call candidate structural variants against the reference and find 685 putative novel SV candidates. We propose this workflow as a potential solution to assemble structurally complex chromosomes, or the study of very large plant or animal
dna - Are human chromosomes connected or separate molecules? - Biology Stack Exchange
Each chromosome is a pair of distinct, separate DNA molecules. A chromosome of an eukaryotic cell nucleus is a (long) helix of two linear molecules and so has two ends, which are called telomeres. DNA naturally forms a double helix with its complementary DNA molecule, and the double helix can further curl in what are called supercoils.. In humans, the chromosomes occur in 23 pairs (totaling 46). Except for the sex chromosome pair, each member of the pair is identical in appearance in a karyotype (picture) and each such pair has a number assigned from 1 to 22; the numbering generally follows the size of the chromosome, with chromosome 1 being the longest. In mammals, the sex chromosomes in a male are quite different in size and are labelled X and Y; a female has two identical X chromosomes.. ...
Novel read density distribution score shows possible aligner artefacts, when mapping a single chromosome<...
TY - JOUR. T1 - Novel read density distribution score shows possible aligner artefacts, when mapping a single chromosome. AU - Naumenko, Fedor M.. AU - Abnizova, Irina I.. AU - Beka, Nathan. AU - Genaev, Mikhail A.. AU - Orlov, Yuriy L.. PY - 2018/2/9. Y1 - 2018/2/9. N2 - Background: The use of artificial data to evaluate the performance of aligners and peak callers not only improves its accuracy and reliability, but also makes it possible to reduce the computational time. One of the natural ways to achieve such time reduction is by mapping a single chromosome. Results: We investigated whether a single chromosome mapping causes any artefacts in the alignments performances. In this paper, we compared the accuracy of the performance of seven aligners on well-controlled simulated benchmark data which was sampled from a single chromosome and also from a whole genome. We found that commonly used statistical methods are insufficient to evaluate an aligner performance, and applied a novel measure of a ...
Chromosome Disorders | Harrisons Principles of Internal Medicine, 19e | AccessMedicine | McGraw-Hill Medical
Since these early discoveries, the techniques for analysis of human chromosomes, and DNA in general, have gone through several revolutions, and with each technical advancement, our understanding of the role of chromosomal abnormalities in human disease has expanded. While early studies in the 1950s and 1960s easily identified abnormalities of chromosome number (aneuploidy) and large structural alterations such as deletions (chromosomes with missing regions), duplications (extra copies of chromosome regions), or translocations (where portions of the chromosomes are rearranged), many other types of structural alterations could only be identified as techniques improved. The first important technical advance was the introduction of chromosome banding in the late 1960s, a technique that allowed for the staining of the chromosomes, so that each chromosome could be recognized by its pattern of alternating dark and light (or fluorescent and nonfluorescent) bands. Other technical innovations ranged from ...
Engineering the 1BS chromosome arm in wheat to remove the Rf (multi) locus restoring male fertility in cytoplasms of Aegilops...
Author(s): Hohn, Christopher E; Lukaszewski, Adam J | Abstract: By removing the Rf (multi) locus from chromosome 1BS of wheat via chromosome engineering we were able to generate a resource for the production of male sterile wheats in three new cytoplasms. Cytoplasmic male sterility is an essential component in the development of many hybrid crops. In wheat (Triticum aestivum L.) only the cytoplasm of T. timopheevi cytoplasm has been extensively tested even though many other cytoplasms are also known to produce male sterility. Among them are the cytoplasms of Ae. kotschyi, Ae. uniaristata and Ae. mutica but here male sterility manifests itself only when the 1RS.1BL rye-wheat translocation is present in the nuclear genome. The location of the male fertility restoring gene on the chromosome arm 1BS (Rf (multi) ) has recently been determined using a set of primary recombinants of chromosome arms 1RS with 1BS. Using this knowledge the same recombinants were used to create chromosome arm 1BS in wheat with a
Comments: Chromosome arrangement and dynamics in the budding bacterium Hyphomonas neptunium
Faithful chromosome replication and segregation are essential for every living cell and must be tightly coordinated with other cell cycle events such as cell division. Our knowledge about prokaryotic chromosome dynamics is based on studies of only a few model organisms that divide by binary fission.... Full description. ...
Elasticity Measurements Show the Existence of Thin Rigid Cores Inside Mitotic Chromosomes | Journal of Cell Biology |...
The presence of a single backbone of nonhistone proteins (a scaffold), responsible for the organization of metaphase chromosomes, has been postulated in the past (Paulson and Laemmli, 1977). However, the existence of the scaffold structure in intact mitotic chromosomes has remained controversial (Earnshaw, 1991). Indeed, the scaffold was observed only upon treatment of mitotic chromosomes with different detergents and salts and thus it was not clear whether the observed structure was not an artifact due to the precipitation of high molecular weight chromosomal proteins (Okada and Comings, 1980; Hirano and Mitchison, 1993). For example, the first biochemically defined component of the scaffold was topo II, but depletion of topo II from in vitro assembled chromosomes (using salt extraction, as in Hirano and Mitchison, 1993) did not change their elastic properties (data not shown). Additionally, within the most sophisticated version of this model, the scaffold and the chromatin loops form an ...
File:Human idiogram- X chromosome diseases.jpg - Embryology
Idiogram Chromosome Banding - The term refers to the light and dark pattern, seen after staining with a dye, of individual chromosomes identified in metaphase. It is only in meiosis and mitosis during metaphase that chromosomes can be easily identified, during the normal cell life (interphase) the chromosomes are unravelled and distributed within the nucleus in chromosome territories. A band is that part of a chromosome which is clearly distinguishable from nearby regions by appearing darker or brighter with one or more banding techniques ...
FISH of rDNA probes on polytene chromosomes of species | Open-i
FISH of rDNA probes on polytene chromosomes of species from the subgenus Chironomus with multiple localization of hybridization sites. aChironomusagilisbChirono
Chromosomes, ageing and cancer
Theres a chromosome that got lost and ended up in the wrong cell. That is how chromosome instability results in aneuploidy. Aneuploidy means that cells have the wrong number of chromosomes. A well-known form of aneuploidy is Down Syndrome, where patients have an extra copy of chromosome 21 in all of their cells.. Trained as a biotechnologist and process engineer at Wageningen University, Foijer developed a keen interest in medical research. This led to a PhD project at the Netherlands Cancer Institute NKI in Amsterdam. There I discovered a control mechanism, a sort of emergency brake to stop cell division. But the mechanism came at a price: when these cells started dividing again, they were susceptible to chromosome instability, a failure to maintain the correct number of chromosomes.. Aneuploidy probably predisposes cancer. Two thirds of cancer cells show chromosome instability resulting in aneuploidy. Aneuploidy probably predisposes cells to cancer. But not all cells with the wrong number ...
Genetic Resources, Chromosome Engineering, And Crop Improvement: Vol 5 1 Edition (ISBN) 1420047396 Lowest Price - Home & Cash...
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The Escherichia coli chromosome shows two main levels of global organization: macrodomains and replichores. Macrodomains were ...
A chromosome is rearranged to give a ring chromosome, and a linear chromosome. Hence, in hindsight, the first observation of ... Cytogenetic and FISH analyses of his chromosomes found three marker chromosomes: one was a bisatellited chromosome, and two ... Out of the two derived from chromosome 10, one formed a ring and the other a "deleted" version of chromosome 10, labelled as ... The neocentromere can either appear on the linear chromosome or on the ring chromosome, depending on which ever one lacks a ...
In E. coli chromosomes, the origin and terminus of replication divide the genome into oppositely replicated halves called ... The Escherichia coli chromosome shows two main levels of global organization, macrodomains and replichores. ... "Roles for replichores and macrodomains in segregation of the Escherichia coli chromosome". EMBO Rep. 6 (6): 557-62. doi:10.1038 ...
Sexual and reproductive health
Sperm Chromosomes. Reproductive hazards can affect the chromosomes found in sperm. The sperm and egg each contribute 23 ... The DNA stored in these chromosomes determines what someone will look like and their our bodies will function. Radiation or ... However, little is known about the effects of workplace hazards on sperm chromosomes. Pregnancy. If a damaged sperm does ...
... chromosome 1) to smallest (chromosome 22), with the sex chromosomes (X and Y) shown last. Historically, karyotypes have been ... These include: A translocation between chromosomes 9 and 22, known as the Philadelphia chromosome, occurs in about 20% of adult ... Gains on chromosomes 6 and 8 are often used to refine the predictive value of the Monosomy 3 screen, with gain of 6p indicating ... A translocation between chromosomes 4 and 11 occurs in about 4% of cases and is most common in infants under 12 months. Not all ...
The chromosome number (karyotype) of Sorex araneus varies widely, with a number of distinct "chromosomal races" being present ... The chromosomes. Chapman & Hall, London. p169 Pavlova, Svetlana; Shchipanov, Nikolay (July 2019). "New karyotypes of the common ... This an example of chromosomal polymorphism (chromosomal variability as a result of chromosome fusions or disassociations). ...
Vector (molecular biology)
Artificial chromosomes are manufactured chromosomes in the context of yeast artificial chromosomes (YACs), bacterial artificial ... an organism that transmits disease Human artificial chromosomes Yeast artificial chromosomes Bacterial artificial chromosomes ... chromosomes (BACs), or human artificial chromosomes (HACs). An artificial chromosome can carry a much larger DNA fragment than ... The four major types of vectors are plasmids, viral vectors, cosmids, and artificial chromosomes. Of these, the most commonly ...
The mole cricket chromosome number varies between 19 and 23 chromosomes depending on the part of the world in which they are ... In the fruit fly, Drosophila, one X chromosome in the male is almost the same as two X chromosomes in the female in terms of ... Polysomy of chromosomes 1, 2, 4, 5, and 25 are also frequently involved in canine tumors. Chromosome 1 may contain a gene ... Since canine chromosome 13 is similar to human chromosome 8q, research could provide insight to treatment for prostate cancer ...
Thomas Harrison Montgomery Jr.
ISBN 978-0-226-08471-8. Capanna, Ernesto (2013). "Chromosomes Yesterday: A Century of Chromosome studies". In Ettore Olmo; ... He was first to propose that chromosomes play the dominant role in sex determination, although he rejected the idea that sex ... His most notable research includes early observations of the pairing of maternal and paternal chromosomes during cell division ... was determined by chromosomes alone, and some historians claim he was the first to propose the chromosome theory of inheritance ...
Plant genome assembly
Different large-insert libraries like BACs, P1 artificial chromosomes (PAC), yeast artificial chromosome (YAC) and ... The most common type of large-insert clone is the bacterial artificial chromosome (BAC). With BAC, the genome is first split ... Next, using the map from the first step the contigs are assembled back into the chromosomes. The first complete plant genome ... The genome size of Maize, 2.3 Gb and 10 chromosomes, is significantly larger than that of rice and Arabidopsis. To assemble the ...
Bacterial Chromosomes. Washington, D.C: ASM Press. pp. 389-403. ISBN 1-55581-232-5. Amundsen SK, Taylor AF, Chaudhury AM, Smith ...
The chromosomes (karyotype) of Chilocorus stigma vary from one individual to another, in both the number of chromosomes ( ... The chromosomes. Chapman & Hall, London. p169 Detailed information on C. stigma (Articles with short description, Short ... aneuploidy) and their structure (chromosomal polymorphism). The variability occurs as a result of chromosome fusions or ...
List of polymorphisms
Painter T. S. (1933). "A new method for the study of chromosome rearrangements and the plotting of chromosome maps". Science. ... But in this group polymorphism for super-numerary chromosomes and chromosome regions is very strongly developed in many species ... The determining gene (or super-gene) for the inheritance of egg colour is believed to be carried on the W chromosome, which is ... It was found that the various chromosome types do not fluctuate at random, as they would if selectively neutral, but adjust to ...
... refers to only one copy of each chromosome. Some eukaryotes have distinctive sex chromosomes such as the X and Y chromosomes of ... Eukaryotic genomes are composed of one or more linear DNA chromosomes. The number of chromosomes varies widely from Jack jumper ... it consists of one copy of each of the 22 autosomes plus one X chromosome and one Y chromosome. A genome sequence is the ... The Bacterial Chromosome: 525-540. doi:10.1128/9781555817640.ch29. ISBN 9781555812324. "Bacterial Chromosomes". Microbial ...
Human β-globin locus
The human β-globin locus is composed of five genes located on a short region of chromosome 11, responsible for the creation of ...
During the division process, errors commonly occur in attaching the chromosomes to the spindle, estimated to affect 86 to 90 ... This arrangement enhances the likelihood of properly bi-oriented chromosomes and is sometimes referred to as a mechanism for ' ... The time delay allows for tension to be established at bi-oriented chromosomes, so that only syntelic attachments are ... Normal cell division distributes the genome equally between two daughter cells, with each chromosome attaching to an ovoid ...
Handbook of North American Indians
Y Chromosomes. Tatiana M. Karafet, Stephen L. Zegura, & Michael F. Hammer. Pages 831-839. Ancient DNA. Anne C. Stone. Pages 840 ...
Chromosomes & Cancer. 36 (2): 205-206. doi:10.1002/gcc.10159. PMID 12508249. Patton, K.; Cheng, L.; Papavero, V.; Blum, M.; ...
CS1: long volume value, Articles with short description, Short description matches Wikidata, Genes on human chromosome 9, Tumor ... located on chromosome 9 (9p21.3). This gene generates several transcript variants that differ in their first exons. At least ... Chromosomes & Cancer. 14 (3): 189-95. doi:10.1002/gcc.2870140306. PMID 8589035. S2CID 22823227. Liu L, Lassam NJ, Slingerland ...
semiteres shares the chromosome count with its parents, having a chromosome number of n = 17. The taxonomic status of D. ... Subspecies australis is distinguished by its octoploid chromosome count. Chromosomes n = 68. Occurs along the coast of Baja ... This form is diploid or tetraploid, with 17 or 34 chromosomes. A second cytological form occurs near and around the coast of El ... This form is a tetraploid with 34 chromosomes, as opposed to 17. Dudleya attenuata subsp. australis - Caudex 4 to 8 mm thick. ...
John H. Healey
Genes Chromosomes Cancer. 50 (8): 644-53. doi:10.1002/gcc.20886. PMC 3264678. PMID 21584898. Osborne TS, Ren L, Healey JH, et ...
In humans, cortactin is encoded by the CTTN gene on chromosome 11. Cortactin is a thin, elongated monomer that consists of an ... Brookes S, Lammie GA, Schuuring E, de Boer C, Michalides R, Dickson C, Peters G (April 1993). "Amplified region of chromosome ... Brookes S, Lammie GA, Schuuring E, de Boer C, Michalides R, Dickson C, Peters G (1993). "Amplified region of chromosome band ... Cortactin at the US National Library of Medicine Medical Subject Headings (MeSH) (Genes on human chromosome 11, Cell biology). ...
Genes Chromosomes Cancer. 29 (1): 9-15. doi:10.1002/1098-2264(2000)9999:9999<::AID-GCC1001>3.0.CO;2-#. PMID 10918388. S2CID ...
This translocation results in the fusion of the synovial sarcoma translocation gene on chromosome 18 to one of the SSX genes on ... v t e (Articles with short description, Short description matches Wikidata, Genes on human chromosome X, All stub articles, ... 2003). "A novel fusion gene, SS18L1/SSX1, in synovial sarcoma". Genes Chromosomes Cancer. 37 (2): 195-200. doi:10.1002/gcc. ... 2005). "The DNA sequence of the human X chromosome". Nature. 434 (7031): 325-37. Bibcode:2005Natur.434..325R. doi:10.1038/ ...
The Y is a small metacentric chromosome, while the X is a large metacentric chromosome. The hybrid camel, a hybrid between ... A 2007 study flow sorted camel chromosomes, building on the fact that camels have 37 pairs of chromosomes (2n=74), and found ... The chromosomes of two male Camelidae: Camelus bactrianus and Lama vicugna". Acta Zoologica et Pathologica Antverpiensia. 52: ... 2007). "Cross-species chromosome painting among camel, cattle, pig and human: further insights into the putative ...
... deletion of the short arm of chromosome 7, or partial deletions of chromosome 5. In addition, it has been shown that ... The EVI1 gene is located in the human genome on chromosome 3 (3q26.2). The gene spans 60 kilobases and encodes 16 exons, 10 of ... Since it was first identified in murine myeloid leukemia as a common site of retroviral integration into the chromosome, EVI1 ... CS1: long volume value, Genes on human chromosome 3, All articles with unsourced statements, Articles with unsourced statements ...
... is located within the 7th intron of the EGFL7 gene which resides on human chromosome 9. mir-126* is the complementary ... Genes Chromosomes Cancer. 47 (11): 939-46. doi:10.1002/gcc.20596. PMC 2739997. PMID 18663744. Harris TA, Yamakuchi M, Ferlito M ...
v t e (Articles with short description, Short description is different from Wikidata, Genes on human chromosome, Proteins, All ... Genes Chromosomes Cancer. 2 (2): 103-8. doi:10.1002/gcc.2870020205. PMID 2126193. S2CID 22489747. Toyonaga B, Yoshikai Y, ...
The responsible gene was predicted to be located on the Z chromosome and since male birds are homogametic (ZZ), they can be ... Chromosomes & Cancer. 46 (8): 751-760. doi:10.1002/gcc.20461. ISSN 1045-2257. PMID 17492760. S2CID 9324923. (Chicken plumage ... and recessive white skin on the chicken Z chromosome". Poult. Sci. 67 (4): 530-533. doi:10.3382/ps.0670530. PMID 3165529. ...
Chromosomes & Cancer. 50 (10): 812-22. doi:10.1002/gcc.20902. PMID 21748820. S2CID 9746594. Akçakaya P, Ekelund S, Kolosenko I ...
MedlinePlus: Chromosomes & mtDNA
Parcourir par sujet "ABERRATIONS DES CHROMOSOMES SEXUELS"
Final Report Summary - EPIGEFXY (Epigenetic regulation of the sex chromosomes and male infertility) | FP7 | CORDIS | European...
Slx and Sly are multicopy genes present on the X and Y chromosomes, respectively. We have demonstrated that Slx and Sly are ... The aim of our project was to better understand the epigenetic regulation of sex chromosomes during sperm differentiation and ... Final Report Summary - EPIGEFXY (Epigenetic regulation of the sex chromosomes and male infertility). Human infertility affects ... sperm differentiation requires a high proportion of genes located on the sex chromosomes (i.e. the X and the Y). Expression of ...
Deletion on Chromosome 2 Linked to Epilepsy, Autism
genes Archives - Chromosome Disorder Outreach, Inc
Donate now to increase awareness and research into chromosome disorders. Chromosome Disorder Outreach is a 501(c)(3) non-profit ... You are donating to : Chromosome Disorder Outreach, Inc, a 501(c)(3) non-profit organization. How much would you like to donate ... Chromosome Disorder Outreach is asked frequently how to learn more about the genes associated with human diseases involved in ... Chromosome Disorder Outreach, Inc.. P.O. Box 724. Boca Raton, FL 33429-0724. [email protected] ...
DNA and Chromosomes
Properly condensed chromosomes are necessary for accurate segregation of the sisters after DNA replication. The Escherichia ... MukB is a structural maintenance of chromosome-like protein required for DNA condensation. The complete condensin is a large ... MukBEF, a structural maintenance of chromosome-like protein complex consisting of an ATPase, MukB, and two interacting subunits ... The MukB-topoisomerase IV interaction is required for proper chromosome compaction. Journal of Biological Chemistry ...
Chromosomes walk the line | Nature Cell Biology
This alignment is important for accurate chromosome segregation to daughter cells and startling new data show that chromosomes ... replicated DNA condenses into chromosomes that conspicuously align at the equator of the microtubule-based spindle. ... Chromosome segregation is mediated by a complex microtubule-based spindle1. Spindle microtubules attach to chromosomes through ... This alignment is important for accurate chromosome segregation to daughter cells and startling new data show that chromosomes ...
Distribution of DYZ2 repetitive sequences on the human Y chromosome
Unzipped chromosomes pass on parental stress | New Scientist
The chromosome may contain regions that promote their DNAs spread by killing sperm that carry Y chromosomes. However, Y ... A rat without a Y chromosome could be a glimpse of our genetic future ... Modern humans evolved a selfish X chromosome after Africa exodus. ... the densely packed DNA that makes up chromosomes. ... Unzipped chromosomes pass on parental stress. Health 27 June ...
... to observable changes in its chromosomes. These experiments led to the construction of ... Other articles where chromosome map is discussed: Calvin Blackman Bridges: … ... to observable changes in its chromosomes. These experiments led to the construction of "gene maps" and proved the chromosome ... In principle at least, such maps could be prepared even if the chromosomes, not to speak of the chiasmata at meiosis, were ...
Browsing by Subject "Chromosomes, Insect"
Knowledge of Chromosomes Founded Synthetic Species | Science News
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).. ...
Medical Definition of Acentric chromosome
Acentric chromosome: A fragment of a chromosome (one of the microscopically visible carriers of the genetic material DNA) that ... of the chromosome essential for the division and the retention of the chromosome in the cell) and so is lost when the cell ... Medical Definition of Acentric chromosome. *Medical Editor: Charles Patrick Davis, MD, PhD ...
Chromosomes (article) | Khan Academy
NIMH » Adults: X & Y Chromosome Variations
Lists IRP clinical trials on X and Y chromosome variations recruiting adults. ... Adults: X & Y Chromosome Variations. Brain Imaging of Childhood Onset Psychiatric Disorders, Endocrine Disorders and Healthy ... We will also look at brain changes and development in people with different developmental disorders, including sex chromosome ...
Category:Human chromosome 1 - Wikimedia Commons
... human chromosome 1; صبغي 1; χρωμόσωμα 1; Chromosoma 1; cromosoma umano; মানব ক্রোমোজম; chromosome humain; 人類染色體; humant ... Human chromosome 01 with ASD genes from IJMS-16-06464.png 644 × 2,828; 582 KB. ... Media in category "Human chromosome 1". The following 50 files are in this category, out of 50 total. ... Human chromosome 01 from Gene Gateway - with label.png 1,301 × 2,340; 403 KB. ...
Chromosomes of Garden Roses
Chromosome Surveys of Human Populations: between Epidemiology and Anthropology | MPIWG
All about Chromosome. FACTS: Chromosomes are threadlike structures inside of cells that store genetic information. They are ... Thus, "chroma" or color is the basis of the word chromosome.. The DNA within chromosomes contains the genetic code that ... The ends of chromosomes are marked with DNA sequences called telomeres. These are like plastic tips at the ends of shoelaces, ... DNA is so tightly wound in each chromosome that the entire human genetic code of 3 billion base pairs fits in an area of just 6 ...
chromosome | Office for Science and Society - McGill University
Chromosome 2 Fusion 2
The available genomic data shows that the sequence features encompassing the purported chromosome 2 fusion site are too ... The chromosome 2 fusion is thought to account for the fact that humans have only 46 (2N) chromosomes and the great apes, ... Fan, Y. et al., Gene content and function of the ancestral chromosome fusion site in human chromosome 2q13-2q14.1 and ... The numbers refer to chromosome bands-sections of the chromosome that can be visualized by stains and dyes or other techniques ...
Chromosome News, Articles and Research - Page 3
... the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled ... Y chromosome loss in men can lead to deadly heart failure, research shows The loss of the male sex chromosome as many men age ... Sometimes cleaved chromosomes do not recover and genomic stability is compromised - which in the long run might promote cancer ... Men with hematopoietic mosaic loss of Y chromosome have worse prognosis for heart failure research group led by Dr. Soichi Sano ...
Y chromosome - Scope
Sequencing all 24 human chromosomes uncovers rare disorders | National Institutes of Health (NIH)
A trisomy is a condition in which there are three instances of a certain chromosome instead of the standard two. ... Sequencing all 24 human chromosomes uncovers rare disorders Study from NIH and other institutions may help improve prenatal ... "Extending our analysis to all chromosomes allowed us to identify risk for serious complications and potentially reduce false- ... Conceptual image of a cell karyotype exhibiting trisomy, three copies of one chromosome. Darryl Leja, NHGRI. ...
Sex Chromosomes Hold the Secret to Female Longevity | UC San Francisco
... suggests an important role for the second X chromosome, which is present in female mammals. The X chromosome contains many ... Sex Chromosomes Hold the Secret to Female Longevity Female Biology - Two Xs and Ovaries - Extends Life and Protects Mice From ... In the FCG mice, Sry has been moved to a different chromosome that does not determine sex, so it can be inherited whether or ... The Y chromosome, present only in males, contains very few genes other than those that create secondary sex characteristics, ...
A rare gene variant in the X chromosome TLR7 | EurekAlert!
Life sciences/Genetics/Molecular genetics/Genetic material/DNA/Chromosomes/Sex chromosomes/X chromosomes ... A rare gene variant in the X chromosome TLR7 gene is associated with a five times greater risk of severe COVID-19, in study of ... A rare gene variant in the X chromosome TLR7 gene is associated with a five times greater risk of severe COVID-19, in study of ... A rare gene variant in the X chromosome TLR7 gene is associated with a five times greater risk of severe COVID-19, in study of ...
Stabilizing chromosome ends may treat age-related disease
"Our genetic material is tightly packed into thread-like structures called chromosomes and at the ends of the chromosomes are ... The study, published in the journal Cell Metabolism, demonstrates that shortening of telomeres - the ends of the chromosomes - ... Telomeres work like the plastic tips at the end of shoelaces; they prevent chromosomes from unraveling or sticking to each ... play an important role in maintaining cell fitness by affecting many metabolic processes and repairing damaged chromosomes. The ...
Analysis of Chromosome Information | 13 | Plant Chromosomes | Kiichi F
This chapter describes the flow of a chromosome analysis using an IBAS (Zeiss/Kontron) image analyzer. NIH Image is constructed ... This chapter describes the flow of a chromosome analysis using an IBAS (Zeiss/Kontron) image analyzer. NIH Image is constructed ... The chapter also describes a basic image analysis procedure for plant chromosomes to obtain the density distribution of a ... The application of image technology to human chromosome research began in the 1960s as diagnostic demands increased. Automatic ...
Medical Genetics: Chromosome Studies | University Hospitals
Medical Genetics: Chromosome Studies. What are chromosome studies?. Chromosomes are stick-shaped structures in the middle of ... Special tests called chromosome studies can look at chromosomes to see what type of problem a person has. Chromosome studies ... The chromosomes are stained so that they can be seen with a microscope. The chromosomes look like strings with light and dark ... Extended banding chromosome studies. These types of studies are also known as high resolution chromosome studies. These studies ...
PairsAbnormalitiesChimpanzee chromosomes 2A and 2BHumansDiploidStructuresLearn more about rare chromosome disordersHaploidGenome assemblyAberrationsDifferent combinations of chromosomesChanges in chromosomesGeneticChromosomalResearchersRare chromosomeEnds of chromosomesPair of chromosomesStudy of chromosomesTrisomyAneuploidySegregationPrevent chromosomesSequencesHybridizationAbnormalCellsHomologousGeneticsKaryotypeGenomesDisordersTelomeresMicrotubulesCopiesDeletionFluorescenceKaryotypingMitoticShoelacesDisorder Outreach2021ChimpanzeesPhiladelphiaGenomicSequencingGenes locatedContentSpeciesChromatinInheritanceTissueStructuralMtDNASequenceMalesMicroscopeCellDeletionsDrosophilaActive genesPaternal
- Most human cells have two pairs of 23 chromosomes, one pair from your mother and the other from your father, for a total of 46 chromosomes. (giantmicrobes.com)
- DNA is so tightly wound in each chromosome that the entire human genetic code of 3 billion base pairs fits in an area of just 6 microns, 10 times smaller than the diameter of hair! (giantmicrobes.com)
- Each cell has 46 chromosomes grouped in 23 pairs. (uhhospitals.org)
- Cells prefer to have matching pairs of chromosomes, with an even number in total. (thetech.org)
- There are twenty-two pairs of chromosomes which are referred to as autosomes, because they do not determine the sex of an individual. (ntsad.org)
- Chromosome 15 is one of the 23 pairs of chromosomes in humans. (bionity.com)
- Chromosome 15 spans about 106 million base pairs (the building material of DNA ) and represents between 3% and 3.5% of the total DNA in cells . (bionity.com)
- For these reasons, it wasn't until 1956 that the correct number of 46 human chromosomes (23 pairs) was clearly demonstrated. (the-scientist.com)
- Key to connecting chromosomes to symptoms and traits is the karyotype, a size-order alignment of chromosome pairs in a chart. (the-scientist.com)
- 1) There are 23 pairs of chromosomes found in the nucleus of our cells - one set from each parent. (exploringnature.org)
- I Technically, these chromosomes could be any of the 22 pairs of chromosomes (out of 23 pairs humans have). (sciencejewelry1824.shop)
- Every human cell contains 23 pairs of chromosomes. (cdc.gov)
- Diploid organisms, such as humans, have chromosomes that come in homologous pairs (except for the sex chromosomes), with each parent contributing one chromosome per homologous pair. (maplesoft.com)
- The order of bases on all twenty-three pairs of human chromosomes. (flashcardmachine.com)
- Extending noninvasive prenatal screening to all 24 human chromosomes can detect genetic disorders that may explain miscarriage and abnormalities during pregnancy, according to a study by researchers at the National Institutes of Health and other institutions. (nih.gov)
- FISH can be used to find chromosome abnormalities that may not show up in an extended banding chromosome study. (uhhospitals.org)
- Since then, the field of cytogenetics-linking chromosome abnormalities with syndromes-has proceeded more or less in fits and starts, with key developments in chromosome preparation explaining more and more once mysterious medical conditions. (the-scientist.com)
- This arrest is caused by an abnormal expression of genes, often as a result of chromosomal translocations or abnormalities of chromosome number. (medscape.com)
- RUNX1T1 FISH for the detection of cryptic and complex rearrangements when abnormalities involving chromosome band 8q22 are observed in patients with AML. (bvsalud.org)
- The test looks for abnormalities in the baby's chromosomes. (medlineplus.gov)
Chimpanzee chromosomes 2A and 2B3
- In addition, no ortholog for a cryptic centromere homologous to the alphoid sequence at human chromosome 2 exists on chimpanzee chromosomes 2A and 2B. (creation.com)
- Depiction of a hypothetical scenario where chimpanzee chromosomes 2A and 2B supposedly fuse to form human chromosome 2. (creation.com)
- It is so obvious that scientists have renamed these chimpanzee chromosomes 2a and 2b! (thetech.org)
- Dresden and Leipzig researchers find that stem cells in the developing brain of modern humans take longer to divide and make fewer errors when distributing their chromosomes to their daughter cells, compared to those of Neanderthals. (news-medical.net)
- How did humans go from 48 to 46 chromosomes? (thetech.org)
- I've been reading about how humans went from 48 to 46 chromosomes. (thetech.org)
- Humans have 46 chromosomes in each diploid cell. (nature.com)
- In turn, this must mean the Y chromosome has lost 900-55 active genes over the 166 million years that humans and platypus have been evolving separately. (oniscience.com)
- Homologous chromosomes, sister chromatids, and haploid/diploid. (khanacademy.org)
- Diploid describes a cell that contain two copies of each chromosome. (nature.com)
- In diploid cells, one set of chromosomes is inherited from the individual's mother, while the second is inherited from the father. (nature.com)
- The total number of chromosomes in diploid cells is described as 2n, which is twice the number of chromosomes in a haploid cell (n). (nature.com)
- Spindle microtubules attach to chromosomes through kinetochores - paired structures that are associated with the centromeric heterochromatin of each sister chromatid on a chromosome. (nature.com)
- Chromosomes are threadlike structures inside of cells that store genetic information. (giantmicrobes.com)
- Our genetic material is tightly packed into thread-like structures called chromosomes and at the ends of the chromosomes are particular pieces of DNA called telomeres. (bcm.edu)
- Chromosomes are stick-shaped structures in the middle of each cell in the body. (uhhospitals.org)
- Ji, Y. and Wei, J. (2013) Isoform Inference From RNA-Seq Samples Based on Gene Structures on Chromosomes. (scirp.org)
- Telomeres are structures at the ends of chromosomes that contain repetitive stretches of DNA. (cdc.gov)
Learn more about rare chromosome disorders2
- Physicians, genetic counselors, therapists and other healthcare professionals, register now to help us learn more about rare chromosome disorders: the associated symptoms, new research and evolving treatments. (chromodisorder.org)
- All medical information is held strictly confidential and helps researchers learn more about rare chromosome disorders. (chromodisorder.org)
- A haploid base number of × = 16 chromosomes is likely. (mendeley.com)
- Germ line cells are haploid, which means they contain a single set of chromosomes. (nature.com)
- Key protocols for chromosome-level genome assembly of the Scapharca (Anadara) broughtonii. (protocols.io)
- Outcomes evaluated included sperm parameters, DNA damage and numerical chromosome aberrations (aneuploidy (disomy, nullisomy) or diploidy). (cdc.gov)
Different combinations of chromosomes2
- The researchers gave experimental mice four different combinations of chromosomes and gonads: the two found in nature - XX with ovaries and XY with testes - and two others created in the laboratory - XX testes and XY ovaries. (ucsf.edu)
- For example, wild mice have many different combinations of chromosomes because their chromosomes can so easily stick together. (thetech.org)
Changes in chromosomes2
- This test is another way to look for changes in chromosomes. (uhhospitals.org)
- As a major form of genomic instability, chromosomal instability comprises aberrant chromosome numbers (i.e., aneuploidy or polyploidy) and structural changes in chromosomes. (frontiersin.org)
- Read about each of the human chromosomes and mitochondrial DNA (mtDNA) and the health implications of genetic changes. (medlineplus.gov)
- A fragment of a chromosome (one of the microscopically visible carriers of the genetic material DNA) that is lacking a centromere (the "waist" of the chromosome essential for the division and the retention of the chromosome in the cell) and so is lost when the cell divides. (medicinenet.com)
- The DNA within chromosomes contains the genetic code that describes the physical characteristics of every known life form. (giantmicrobes.com)
- Extending our analysis to all chromosomes allowed us to identify risk for serious complications and potentially reduce false-positive results for Down syndrome and other genetic conditions," said Diana W. Bianchi, M.D., senior author of the study and chief of the Prenatal Genomics and Therapy Section at NIH's National Human Genome Research Institute (NHGRI). (nih.gov)
- Now, scientists at UC San Francisco have zeroed in on a possible genetic mechanism for this highly durable phenomenon, that - while it does not preclude the influence of other biological, social and environmental factors - suggests an important role for the second X chromosome, which is present in female mammals. (ucsf.edu)
- As the cell's machinery raced to put the chromosome(s) back together, bits of genetic material might be left out and others re-assembled in the wrong order - or even from the wrong chromosome. (scienceinschool.org)
- Identifying genes on each chromosome is an active area of genetic research. (bionity.com)
- 4) Because we get two sets of chromosomes , it means that we actually have two sets of genetic instructions - so two genes for each potential trait. (exploringnature.org)
- Within organisms , genetic information generally is carried in chromosomes , where it is represented in the chemical structure of particular DNA molecules . (wikipedia.org)
- It works by triggering a genetic pathway starting with a gene called SOX9 which is key for male determination in all vertebrates, although it does not lie on sex chromosomes. (oniscience.com)
- For example, children with Down syndrome can be born with a heart defect and Down syndrome is a genetic condition in which children have extra genetic material known as chromosome number 21 in every cell of their body, and it's thought that this extra genetic material causes the infant's heart not to develop normally during the pregnancy. (cdc.gov)
- In other circumstances, the testing method was neither germline or somatic, but used other means for identifying genetic risk (e.g., family history), or diagnosis, including biomarkers (objective measures of a biological state or condition within cells or organisms) and cytogenetics (the study of chromosomes and their inheritance). (cdc.gov)
- Of 57 children with a medical condition, 54 percent had a neurological disorder, 30 percent had pulmonary disease, 25 percent had a chromosome or genetic disorder and 19 percent had congenital heart disease or other cardiac disease. (cdc.gov)
- MukB also interacts with the ParC subunit of the cellular chromosomal decatenase topoisomerase IV, an interaction that is required for proper chromosome condensation and segregation in Escherichia coli , although it suppresses the MukB ATPase activity. (jbc.org)
- This chromosomal change deletes the region of chromosome 15 that includes the UBE3A gene. (bionity.com)
- The researchers applied a method called 'Hi-C' (High-throughput Chromosome Conformation Capture) to samples from patients with developmental disorders suspected to be caused by chromosomal rearrangements. (mpg.de)
- The classical analysis of chromosomal defects is done by a karyogram, which is a microscopic view of stained chromosomes. (mpg.de)
- For each, researchers calculated a normalized chromosome denominator quality (NCDQ), which measures the likelihood that a sample has the standard two copies of each chromosome. (nih.gov)
- The researchers found that having both female sex chromosomes and female gonads extended life in mice that were 12 to 30 months old, the mouse equivalent of midlife to old age. (ucsf.edu)
- Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. (bionity.com)
- Researchers are working to identify genes on chromosome 15 that are responsible for the characteristic features of Prader-Willi syndrome. (bionity.com)
- Since the 1 920s, when researchers began to study chromosomes, the analysis of human chromosomes has presented a particularly tough technological challenge, simply because there are so many of them. (the-scientist.com)
- Help us in our efforts to raise awareness of rare chromosome disorders by visiting our online store. (chromodisorder.org)
- We now support 30,000 people with rare chromosome & gene disorders. (rarechromo.org)
- Sharing for #CarersRightsDay in support of all carers, including those caring for people with rare chromosome & gene disorders, who are so often forgotten. (rarechromo.org)
- Rare Chromosome Disorder Support Group. (rarechromo.org)
Ends of chromosomes2
- The ends of chromosomes are marked with DNA sequences called telomeres. (giantmicrobes.com)
- Scientists know that TP53 helps prevent chromosomes from fraying at the ends, by protecting telomeres - the caps that keep the ends of chromosomes together. (scienceinschool.org)
Pair of chromosomes2
- People get one of each pair of chromosomes from their mother and one of each pair from their father. (cdc.gov)
- This suggests the mammal X and Y were an ordinary pair of chromosomes not that long ago. (oniscience.com)
Study of chromosomes1
- Cytogenetics is the study of chromosomes. (uhhospitals.org)
- Conceptual image of a cell karyotype exhibiting trisomy, three copies of one chromosome. (nih.gov)
- A trisomy is a condition in which there are three instances of a certain chromosome instead of the standard two. (nih.gov)
- It is primarily caused by trisomy of chromosome 21 (see the image below), which gives rise to multiple systemic complications as part of the syndrome. (medscape.com)
- Accurate chromosome segregation is essential in cell division to ensure that aneuploidy is avoided, which causes birth defects and contributes to cancer initiation and progression. (nature.com)
- This alignment is important for accurate chromosome segregation to daughter cells and startling new data show that chromosomes cooperate with one another to achieve this alignment. (nature.com)
- Within bundles, filament overlap length marked by the cross-linking protein PRC1 decreases during anaphase as chromosome segregation slows. (nih.gov)
- Chromosome segregation distance and rate are increased in two human cell lines when microtubule bundle assembly is prevented via PRC1 knockdown. (nih.gov)
- they prevent chromosomes from unraveling or sticking to each other," said Dr. Ergun Sahin , lead investigator and assistant professor in the Huffington Center on Aging and the Department of Molecular Physiology and Biophysics at Baylor. (bcm.edu)
- Chromosome length assembly sequences were aligned to the genomes of related species to reveal corresponding chromosomes. (researchgate.net)
- Recently published research papers are now demonstrating how Human cells can rewrite RNA sequences into DNA Chromosomes. (ethealing.com)
- In other words, the linkage maps of the chromosomes are really summaries of many statistical observations on the outcomes of hybridization experiments. (britannica.com)
- Chromosome staining and hybridization techniques do not provide detailed DNA sequence information, but rather indicate putative areas of homology. (creation.com)
- Most embryos stop developing and perish within days of fertilization, usually because they have an abnormal number of chromosomes. (news-medical.net)
- When a chromosome is abnormal, it can cause health problems in the body. (uhhospitals.org)
- The study can look for abnormal amounts or shapes of chromosomes. (uhhospitals.org)
- This leukemia occurs when genes on chromosome 15 switch places with some genes on chromosome 17 and an abnormal gene called PML-RARA is made. (cancer.gov)
- these abnormal chromosomes are often observed in cancer cells. (cdc.gov)
- BACKGROUND: Isodicentric Y chromosome (idic(Y)) is the most commonly reported aberration of the human Y chromosome, which is an important cause of abnormal sexual development. (bvsalud.org)
- We have developed an antibody to study its pattern of expression and observed that SSTY is specifically express in differentiating germ cells where it colocalizes with the sex chromosomes. (europa.eu)
- In mammalian cells, each kinetochore binds directly to the ends of 10-30 microtubules, which then bundle together to form kinetochore-fibres that link chromosomes to spindle poles. (nature.com)
- research group led by Dr. Soichi Sano, a specially appointed lecturer in the Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka Metropolitan University, revealed that men with hematopoietic mosaic loss of Y chromosome (mLOY) - meaning men with an increase, in the blood, of cells that have lost the male sex chromosome - have a worse prognosis for heart failure due to fibrosis progression in the heart. (news-medical.net)
- The cells in the sample are stained with fluorescent dyes that will only attach to certain parts of chromosomes. (uhhospitals.org)
- Here, we use high-resolution live-cell imaging to analyze individual microtubule bundles, growing filaments, and chromosome movement in dividing human cells. (nih.gov)
- We propose that microtubule overlap length reduction, typically linked to pushing forces generated within filament bundles, is needed to properly restrict spindle elongation and position chromosomes within daughter cells. (nih.gov)
- Nearly all the cells in the human body carry two homologous, or similar, copies of each chromosome. (nature.com)
- The PPL scientists introduced a gene in the chromosomes of livestock cells in culture. (wired.com)
- Usually the total chromosome count was determined in 10-15 cells, but if mosaicism was suspected then 30 or more cell counts were undertaken . (who.int)
- Chromosomes are parts of cells that contain your genes. (medlineplus.gov)
- Each chromosome in a given homologous pair represents the same genes, but with different expressions (called alleles ) of those genes. (maplesoft.com)
- Chromosomes are analyzed by healthcare providers trained in cytogenetic technology and genetics. (uhhospitals.org)
- The development and application of new techniques for the study of human chromosomes has revealed that the genetics of sex determination in man appears to be different from any other system so far known and may still be accommodated within the limits of a balance theory. (semanticscholar.org)
- A karyotype is a single person's set of chromosomes. (uhhospitals.org)
- Two patients showed a t(8;14) and a t(8;10) variation, respectively, with a morphologically normal-appearing chromosome 21 in each initial karyotype. (bvsalud.org)
- DNA, chromosomes, and genomes. (khanacademy.org)
- The advent of high-throughput DNA sequencing and its accompanying technologies has largely replaced these earlier technologies for comparing both chromosomes and genomes. (creation.com)
- Donate now to increase awareness and research into chromosome disorders. (chromodisorder.org)
- We will also look at brain changes and development in people with different developmental disorders, including sex chromosome variations. (nih.gov)
- The data actually suggest that the core ~800 bp region containing the fusion site is not a unique cryptic and degenerate head-to-head fusion of telomeres, but a distinct motif that is represented throughout the human genome with no orthologous counterpart in the chimpanzee genome on either chromosome 2A or 2B. (creation.com)
- Telomeres are end-cap DNA repeat motifs (TTAGGG) n located at the termini of linear mammalian chromosomes, recently reviewed by Tomkins and Bergman. (creation.com)
- The study, published in the journal Cell Metabolism , demonstrates that shortening of telomeres - the ends of the chromosomes - impairs a class of enzymes called sirtuins, which play an important role in maintaining cell fitness by affecting many metabolic processes and repairing damaged chromosomes. (bcm.edu)
- If TP53 is faulty, Jan and colleagues speculate, telomeres could be compromised, and chromosomes could stick to each other. (scienceinschool.org)
- To segregate faithfully, all chromosomes must form bi-oriented attachments to spindle microtubules in which each of the paired kinetochore fibres extend to opposite spindle poles. (nature.com)
- In the spindle midzone, microtubules from opposite half-spindles form bundles between segregating chromosomes. (nih.gov)
- Because of the way data have been analyzed, typical genomic tests performed during pregnancy have targeted extra copies of chromosomes 21, 18 and 13, but rarely evaluated all 24 chromosomes. (nih.gov)
- People normally have two copies of this chromosome. (bionity.com)
- The following conditions are caused by changes in the structure or number of copies of chromosome 15. (bionity.com)
- Because the copy of the UBE3A gene inherited from a person's father (the paternal copy) is normally inactive in the brain, a deletion in the maternal chromosome 15 results in no active copies of the UBE3A gene in the brain. (bionity.com)
- In 3% to 7% of cases, Angelman syndrome occurs when a person has two copies of the paternal chromosome 15 instead of one copy from each parent. (bionity.com)
- People with paternal UPD for chromosome 15 have two copies of the UBE3A gene, but they are both inherited from the father and are therefore inactive in the brain. (bionity.com)
- People normally have two copies of this chromosome in each cell, one copy from each parent. (bionity.com)
- While all DNA is stained blue, a specific sequence stained pink appears duplicated in one of the two copies of chromosome 17, but not the other. (mpg.de)
- A female has two copies of the FMR1 gene, one on each of her two X chromosomes. (cdc.gov)
- A region of a chromosome that contains multiple copies of a core DNA sequence that are arranged in a repeating fashion. (flashcardmachine.com)
- In most cases (about 70%), people with Angelman syndrome have a deletion in the maternal copy of chromosome 15. (bionity.com)
- Therefore, a person with a deletion in the paternal chromosome 15 will have no active genes in this region. (bionity.com)
- A boy with 13.34-Mb interstitial deletion of chromosome 4p15. (lww.com)
- Chromosomes stained with fluorescence dyes under the microscope. (mpg.de)
- Karyotyping is a way of looking at the set of chromosomes a person has. (uhhospitals.org)
- CMA can find chromosome problems with more detail than karyotyping or FISH. (uhhospitals.org)
- Rapid degradation of condensin I and condensin II - two essential regulators of mitotic chromosome structure - revealed that both complexes are individually required for cell division in precursor lymphocytes, but not in their differentiated peripheral lymphocyte derivatives. (elifesciences.org)
- These are like plastic tips at the ends of shoelaces, protecting chromosomes from fraying and degenerating. (giantmicrobes.com)
- Chromosome Disorder Outreach is asked frequently how to learn more about the genes associated with human diseases involved in any chromosome disorder. (chromodisorder.org)
- Chromosome Disorder Outreach is a 501(c)(3) non-profit organization. (chromodisorder.org)
- On October 29, 2021, the Food and Drug Administration granted accelerated approval to asciminib (Scemblix, Novartis AG) for patients with Philadelphia chromosome-positive chronic myeloid leukemia (Ph+ CML) in chronic phase (CP), previously treated with two or more tyrosine kinase inhibitors (TKIs), and approved asciminib for adult patients with Ph+ CML in CP with the T315I mutation. (fda.gov)
- Retrieved from https://www.hematology.org/education/clinicians/drug-resources/fda-alerts/2021/fda-approves-asciminib-for-philadelphia-chromosome-positive-chronic-myeloid-leukemia . (hematology.org)
- In fact, when you compare human and chimpanzee chromosomes, you can pretty easily see how chromosomes 12 and 13 of chimpanzees stuck together to give our chromosome 2. (thetech.org)
- The treatment regimen for patients with ALL is determined primarily by the Philadelphia chromosome status of the leukemia and the age of the patient. (medscape.com)
- Patients with Philadelphia chromosome-positive (Ph+) ALL receive a tyrosine kinase inhibitor (TKI) in combination with chemotherapy. (medscape.com)
- Philadelphia-chromosome positive ALL, ie. (who.int)
- Our analysis of the available genomic data shows that the sequence features encompassing the purported chromosome 2 fusion site are too ambiguous to accurately infer a fusion event. (creation.com)
- While the chromosome 2 fusion model has been routinely discussed in reviews of human evolution, very little new supporting genomic data, although readily available for analysis, has been forthcoming. (creation.com)
- Sometimes cleaved chromosomes do not recover and genomic stability is compromised - which in the long run might promote cancer. (news-medical.net)
- Human DNA gene sequencing has long been known for Chromosome 8, commonly known as the God Gene for its specific effect on Human Behaviors (see definition in next section). (ethealing.com)
- All "Vaccine" Injections contain the spiked protein which has the same sequencing (coding) as Chromosome 8, VMAT2. (ethealing.com)
- Copy number variation sequencing showed the duplication of whole Y chromosome. (bvsalud.org)
- In mice and men, sperm differentiation requires a high proportion of genes located on the sex chromosomes (i.e. the X and the Y). Expression of these genes is tightly controlled by epigenetic processes which remain to be studied. (europa.eu)
- Chromosome staining used to achieve visible banding markers yields information related to GC base content, repeat content, CpG island density, and degree of condensation over large areas rather than specific sequence homology. (creation.com)
- Conclusions: A basic chromosome number of x = 16 is reported for the first time for the species M. officinalis. (mendeley.com)
- The mole voles of eastern Europe and the spiny rats of Japan each boast some species in which the Y chromosome, and SRY, have completely disappeared. (oniscience.com)
- His team have shown that chemical or environmental stress detaches a protein called activating transcription factor 2 (ATF-2) from chromatin, the densely packed DNA that makes up chromosomes. (newscientist.com)
- Chromosomes and Inheritance. (bcgcertification.org)
- Chromosome studies are usually done from a small sample of tissue from a person's body. (uhhospitals.org)
- MukBEF, a structural maintenance of chromosome-like protein complex consisting of an ATPase, MukB, and two interacting subunits, MukE and MukF, functions as the bacterial condensin. (jbc.org)
- It is likely that MukBEF compacts DNA via an ATP hydrolysis-dependent DNA loop-extrusion reaction similar to that demonstrated for the yeast structural maintenance of chromosome proteins condensin and cohesin. (jbc.org)
- MukB is a structural maintenance of chromosome-like protein required for DNA condensation. (jbc.org)
- Human Chromosome Explorer™ (HCE) is an advanced, cloud-based, whole genome map assembly and structural variation (SV) analysis software for Bionano Genomics and Nabsys HD-mapping platforms. (structuralvariation.bio)
- The structural chromosome alterations may arise at the chromosome level (e.g., translocations and gains or losses of large portions of chromosomes) or at the nucleotide level, which influence gene structure or expression such as mutations, insertions, deletions, gene amplifications, and gene silencing by epigenetic effects ( Jefford and Irminger-Finger, 2006 ). (frontiersin.org)
- Around 7.000 y.a., human populations from the entire world went through a strong decrease of Y chromosome diversity compared to mtDNA. (openedition.org)
- In order to confront this scenario to other hypotheses, we developed a model of populations displaying different descent and residence rules, with or without competition between lineages, and for each scenario, we computed diversity estimators on the Y chromosome and mtDNA. (openedition.org)
- Obtained results suggest that if violent competition between lineages strongly decreases diversity on the Y chromosome, patrilineality alone generates a major bottleneck on the Y chromosome with respect to mtDNA. (openedition.org)
- The DNA sequence evidence for a purported inactivated cryptic centromere site on chromosome 2, supposedly composed of centromeric alphoid repeats, is even more ambiguous and untenable than the case for a fusion site. (creation.com)
- From a DNA sequence perspective, it is claimed that human chromosome 2 contains two key regions in its landscape. (creation.com)
- This protein has the identical amino acid coding (sequence) found in Human DNA-Chromosome 8. (ethealing.com)
- The PCR test template (gene sequence) for the "lab test" also is the same as that found on Chromosome 8, and it has also been found in Swabs used to collect nasal cell samples. (ethealing.com)
- Because the enzymes that copy DNA aren't able to continue to the very end of the sequence, a bit of DNA is lost each time the chromosome is copied. (cdc.gov)
- The Y chromosome, present only in males, contains very few genes other than those that create secondary sex characteristics, like male genitals and facial hair, and it is not necessary for survival. (ucsf.edu)
- Females have two X chromosomes (XX), and males have one X and one Y chromosome (XY). (cdc.gov)
- The chromosomes are stained so that they can be seen with a microscope. (uhhospitals.org)
- A pair of stained chromosomes under the microscope. (mpg.de)
- During cell division, replicated DNA condenses into chromosomes that conspicuously align at the equator of the microtubule-based spindle. (nature.com)
- Brain tumours are one of the most common causes of death in children - and may begin when chromosomes are torn apart during cell division. (scienceinschool.org)
- This makes us suspect that these three events are connected," says Jan. "We believe that a TP53 mutation may cause chromosomes to explode, or possibly prevent the cell from reacting properly when they do. (scienceinschool.org)
- In such a scenario, when that cell came to divide, chromosomes that were stuck together could run into problems. (scienceinschool.org)
- Previously interstitial deletions of chromosome 4p have only been rarely described. (lww.com)
- The results reveal several puzzling aspects of Drosophila dot chromosome biology to be possible remnants of its former life as a sex chromosome, such as its minor feminizing role in sex determination or its targeting by a chromosome-specific regulatory mechanism. (semanticscholar.org)
- Prader-Willi syndrome is caused by the loss of active genes in a specific part of chromosome 15, the 15q11-q13 region. (bionity.com)
- In about 70% of cases, Prader-Willi syndrome occurs when the 15q11-q13 region of the paternal chromosome 15 is deleted. (bionity.com)
- The genes in this region are normally active on the paternal copy of the chromosome and are inactive on the maternal copy. (bionity.com)
- To better understand the molecular architecture and origin of the Croatian Bayash paternal gene pool, 151 Bayash Y chromosomes were analyzed for 16 SNPs and 17 STRs and compared with European Romani and non-Romani majority populations from Europe, Turkey, and South Asia. (blogspot.com)