• Whether the morbidity associated with Klinefelter syndrome is a result of hypogonadism and hyperestrogenism or due to abnormal function of X chromosome linked genes is unclear. (medscape.com)
  • 12) and Morgan (Science, '12) have reported the linkage relations of two non-sex-linked genes, black and vestigial. (caltech.edu)
  • Well-known examples are some chromosomal translocations or sex-chromosomal abnormalities and Y-chromosome deletions. (virascience.com)
  • 2] The addition of more than one extra X or Y chromosome to a male karyotype results in variable physical and cognitive abnormalities. (medscape.com)
  • In general, the extent of phenotypic abnormalities, including mental retardation, is directly related to the number of supernumerary X chromosomes. (medscape.com)
  • The genetic controversy about LSD started in 1967 when Cohen, Marinello and Back (22) published a paper suggesting that LSD should be added to the list of substances capable of causing abnormalities in the chromosomes. (druglibrary.net)
  • Of those, 116 (13.2%) had sex chromosome abnormalities and 20(2.3%) had autosomal chromosome abnormalities. (ijfs.ir)
  • In addition to these basic issues concerning leukemia pathogenesis, we are devising new diagnostic procedures for detecting and monitoring leukemia patients based on molecular genetic abnormalities in the malignant cells. (stanford.edu)
  • Chromosomal abnormalities are changes to the number or structure of chromosomes that can lead to birth defects or other health disorders. (solarpoultry.com)
  • Other evidence of chromosomal abnormalities include abnormal sexual development, behavioral disturbances, malignancy (e.g., the Philadelphia chromosome in chronic myelocytic leukemia), and spontaneous abortion. (solarpoultry.com)
  • Trisomy of sex chromosomes is compatible with life, but will cause phenotypic abnormalities. (mindmeister.com)
  • These studies will also examine how aberrations in these mechanisms lead to related diseases such as infertility and genetic abnormalities in offspring. (kyoto-u.ac.jp)
  • Finally, using mouse PGCLCs as our model, we are investigating oocyte development, meiosis, and the effects of sex chromosome abnormalities on fertility. (kyoto-u.ac.jp)
  • The overall incidence of chromosome abnormalities was 5.1% (40 cases), and it contains 27 cases (3.4%) of numerical abnormalities and 13 cases (1.7%) of structural abnormalities. (ogscience.org)
  • Of the sex chromosomal abnormalities, three cases of Turner syndrome and three cases of Kleinefelter syndrome were found. (ogscience.org)
  • Comparative genomic hybridization (aCGH) is a powerful diagnostic tool for detecting DNA copy number gains and losses associated with chromosome abnormalities. (enzolifesciences.com)
  • Similarly, errors can also result in cells with missing or extra chromosomes, a condition known as 'aneuploidy', and can cause severe abnormalities. (biologyideas.com)
  • It seems probable that the scheme outlined in this paper will apply for the case of inversions that do not include the locus of the spindle attachment and for other chromosome aberrations in which crossing-over gives rise to chromatids with two spindle attachments, and where the conditions of meiosis are such that (a) the meiotic spindles are oriented so that the reduced nuclei lie approximately on a single straight line, and (b) only one of the terminal nuclei functions in further development. (caltech.edu)
  • Chromosomal recombination during meiosis and subsequent sexual reproduction play a significant role in genetic diversity . (wikipedia.org)
  • Golic and Hawley are progeny of the Larry Sandler lineage, steeped in the traditions of meiosis, hard-core chromosome mechanics, fly lore and scholarship. (silverchair.com)
  • The failure of homologous CHROMOSOMES or CHROMATIDS to segregate during MITOSIS or MEIOSIS with the result that one daughter cell has both of a pair of parental chromosomes or chromatids and the other has none. (nih.gov)
  • State two ways in which meiosis gives rise to genetic variation. (collepals.com)
  • Cyril Darlington pioneered plant cytogenetics in 1920-30 and made important advances in our understanding of mechanisms of chiasma formation and the behavior of sex chromosomes in meiosis [ 7 ]. (biomedcentral.com)
  • Not limited to mitosis, anaphase also takes place in meiosis, another type of cell division that leads to the creation of sex cells. (biologyideas.com)
  • Both in mitosis and meiosis, anaphase ensures each newly formed cell has a complete and accurate set of chromosomes, thus safeguarding the genetic integrity of an organism. (biologyideas.com)
  • Aberrations in autosomal genes can give rise to a wide range of genetic disorders. (biologyonline.com)
  • Studying autosomal genetic disorders provides valuable insights into disease mechanisms and paves the way for targeted therapies and genetic counseling for the human creed. (biologyonline.com)
  • In his famous textbook The Cell in Development and Heredity , Wilson linked together the independent work of Boveri and Sutton (both around 1902) by naming the chromosome theory of inheritance the Boveri-Sutton chromosome theory (the names are sometimes reversed). (wikipedia.org)
  • Heredity refers to the transmission of genetic information, more precisely genes, from parents to offspring. (freebookcentre.net)
  • Topics covered includes: historical perspective of genetics, inheritance patterns and the chromosomal basis of heredity, sex chromosomes in sex determination and sexual dimorphism, cells reproduce through DNA and nucleic acids, DNA transcribes into RNA that ultimately translates into protein, prokaryotic and eukaryotic genes, genetic basis of cancer and how it relates to the cell cycle. (freebookcentre.net)
  • Using one sentence for each example, explain five lines of evidence in support of the chromosome theory of heredity. (collepals.com)
  • In 1944 it was realized that genetic transformation in bacteria was due to DNA and not protein and that DNA was the molecule responsible for heredity in genes and chromosomes [ 8 ]. (biomedcentral.com)
  • Before fertilization, the cytoplasm of the eggs deposited by race B females is so influenced by the chromosomes present in it, that an interaction between this cytoplasm and the autosomes of race A (introduced by the spermatozoon) results in the development of small testes in males arising from such eggs. (caltech.edu)
  • The mother and father each contribute one set of 22 autosomes and one sex chromosome. (solarpoultry.com)
  • Presentation Summary : Human Chromosomal Disorders Human disorders due to chromosome alterations in autosomes (Chromosomes 1-22). (solarpoultry.com)
  • A ring chromosome is an extremely rare chromosomal aberration, which can occur in autosomes and sex chromosomes. (juniperpublishers.com)
  • Autosomes can be described as the non-sex chromosomes that play diverse roles in the human body like harboring genes for the body's metabolism, functioning, and growth. (biologyonline.com)
  • An important point to note here is that certain autosomes do play a role in phenotypic sex determination! (biologyonline.com)
  • So, we can't say that autosomes have no role in phenotypic sex determination in humans because they play an integral and indispensable role! (biologyonline.com)
  • Human autosomes , the non-sex human chromosomes, are integral components of the human genome . (biologyonline.com)
  • Consisting of 22 pairs, autosomes carry a wealth of genetic information that governs numerous biological processes. (biologyonline.com)
  • The human genome is composed of 23 pairs of chromosomes, with autosomes (22 pairs) comprising the majority. (biologyonline.com)
  • This is why autosomes form the backbone of human genetics as they hold the key to our intricate biological processes and susceptibility to genetic disorders. (biologyonline.com)
  • Conclusion: We observed high frequency of aneuploidy and sex chromosomal mosaicism in azoospermic men and high structural aberrations in males with low sperm quality. (ijfs.ir)
  • So that, high chromosomal aneuploidy was detected in males with lower sperm count and high structural aberration was detected in males with low sperm quality. (ijfs.ir)
  • Aneuploidy - failure of segregation of chromatids during cell division cycle results in the gain or loss of chromosome. (solarpoultry.com)
  • 2. New linkage maps of all the chromosomes are presented. (caltech.edu)
  • Five of these lie in the X-chromosome, and a study of their linkage relations was shown to indicate that the sequence of the five loci concerned is the same in both species, and that the percentages of crossing over in comparable regions, while not indentical, is still not very different. (caltech.edu)
  • Chromosome structure, chromosomal aberrations, linkage and cross-over, and their significance in recombination breeding. (chanakyamandal.org)
  • Morgan, Sturtevant, Bridges and Muller constructed the first genetic linkage maps from recombination studies in crosses made in the fruit fly and from cytological preparations of its polytene salivary gland chromosomes [ 4 - 6 ]. (biomedcentral.com)
  • Topics covered includes: structure and function of genes, chromosomes and genomes, biological variation resulting from recombination, mutation, and selection, population genetics, use of genetic methods to analyze protein function, gene regulation and inherited disease. (freebookcentre.net)
  • Even if they are considered to be intersexual, the abnormality may be induced by any one of at least seven different Minutes, or by other independent combinations of genes, and therefore cannot be used to support the view that there are very few loci involved in the determination of sex. (caltech.edu)
  • The common belief is that they don't have any role to play in sex determination. (biologyonline.com)
  • Figure 2: SOX9 gene on the autosome 17 (long arm) plays an integral role in gonadal sex determination. (biologyonline.com)
  • This finding further highlights the importance of DMRT1 gene in sex determination and differentiation in males. (biomedcentral.com)
  • Sex determination and development in males occurs during the embryonic period, and is initiated by the expression of SRY gene located on the short arm of the Y chromosome. (biomedcentral.com)
  • Elaborating its molecular defects play an imperative role in understanding sex determination and development in the embryo. (biomedcentral.com)
  • Belling(1) suggested that the chromosome rings found in Oenothera by Cleland(2) and others are to be explained as resulting from exchanges of ends between non-homologous chromosomes, so that one chromosome of a given complex is homologous at one end to one chromosome of a second complex, and at the other end to a different chromosome of the second complex. (caltech.edu)
  • Origin, evolution and domestication of crop plants, center of origin, law of homologous series, crop genetic resources- conservation and utilization. (chanakyamandal.org)
  • Using different colors to distinguish chromosomes of maternal and paternal origin, draw a metacentric set of homologous chromosomes at: b. (collepals.com)
  • A recent paper in this journal by Detlefsen(1) is introduced as follows: "There is a well intrenched concept of recent genetics that hereditary factors or genes may be given fairly definite loci on chromosome maps and that these maps correspond to or represent, roughly perhaps, the actual conditions in the chromosome. (caltech.edu)
  • This PDF covers the following topics related to Population Genetics : Introduction to Genetics, Hardy-Weinberg Equilibrium, Genetic Drift and Mutation, Selection, Nonrandom Mating. (freebookcentre.net)
  • This note covers the following topics: quantitative versus qualitative genetics, Hardy-Weinberg law for gene frequency stability in large populations, Relationship and inbreeding, Estimation of breeding values, Inbreeding, crossing and bred structure, Chromosomes and chromosome aberrations, Genetics on hair and coat colour in mammals, Estimating- and biotechnology and disease resistance. (freebookcentre.net)
  • The objective of this note is have a greater awareness and appreciation of classical and molecular genetics with emphasis on genetic material and its formation, transmission, function and organization. (freebookcentre.net)
  • A gene is a segment of deoxyribonucleic acid (DNA) and contains the code for a specific protein that functions in one or more types of cells in the body (see Genes and Chromosomes for a discussion about genetics). (solarpoultry.com)
  • When we discuss the core concepts of Genetics , chromosomes are the first word that pops into our minds. (biologyonline.com)
  • A number of scientific papers have been published indicating that LSD might cause structural changes in the chromosomes, genetic mutations, disturbances of embryonic development, and malignant degeneration of cells. (druglibrary.net)
  • Usurping these processes to deregulate functional pathways is likely simpler than generating mutations or chromosomal aberrations (unless DNA repair is deficient and genetic instability is present). (aacrjournals.org)
  • With no alternative alleles to compensate for those with lethal mutations, haploid drones carrying harmful alleles act as genetic martyrs, leaving behind a population of males with more robust genes to pass on to the next generation. (americanbeejournal.com)
  • Although SLE is generally a complex genetic illness, there are several examples of mutations that can produce a monogenetic form of the illness. (medscape.com)
  • Genetic diseases that are linked to gene mutations on the X CHROMOSOME in humans (X CHROMOSOME, HUMAN) or the X CHROMOSOME in other species. (bvsalud.org)
  • The most common mutations that cause Pelizaeus-Merzbacher disease are duplications of a region of the X chromosome that includes the entire PLP1 gene. (medscape.com)
  • In most cases, Pelizaeus-Merzbacher disease is caused by mutations of PLP1 on the long arm of the X chromosome (Xq22). (medscape.com)
  • Chromosome Duplication" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (harvard.edu)
  • Gonadal development is particularly susceptible to each additional X chromosome, resulting in seminiferous tubule dysgenesis and infertility, as well as hypoplastic and malformed genitalia in polysomy X males. (medscape.com)
  • These matings included at least 500 mass cultures, of which 74 produced hybrid offspring -- a total of 532 females and 635 males, all wild type for the sex -- linked mutant characters used. (caltech.edu)
  • It was shown by Lancefield (1929) that D. pseudoobscura A-B hybrid females, when back-crossed either to A or to B males, give sex-ratios among their offspring that may deviate widely (in either direction) from 1:1. (caltech.edu)
  • Sex chromosomes determine an individual's sex: females have two X chromosomes (XX), and males have an X and a Y chromosome (XY). (solarpoultry.com)
  • Y-chromosome microdeletion syndrome occurs in approximately 7,5% of males with confirmed infertility. (cloudhealthlabs.com)
  • Male cells have only one X chromosome, meaning normally, males are just one color. (joewongcomedy.com)
  • Male calico cats are rare because like human males with Kleinfelter's Syndrome, they suffer from a chromosomal abnormality in which they have 2 X chromosomes along with the Y, instead of one. (joewongcomedy.com)
  • Producing larger sex cells and, in the case of mammals, nurturing a developing fetus, are costly activities, thus limiting the number of offspring females can produce relative to males. (americanbeejournal.com)
  • This mosaicism, due to the presence of the ring Y chromosome and depending upon on the presence or absence of the SRY gene can result in a wide spectrum of manifestations ranging from females with a Turner syndrome-like phenotype to phenotypic males. (juniperpublishers.com)
  • In males, who have only one X chromosome, a mutation in the only copy of the gene in each cell is sufficient to cause the condition. (medlineplus.gov)
  • Psoni S, Sofocleous C, Traeger-Synodinos J, Kitsiou-Tzeli S, Kanavakis E, Fryssira-Kanioura H. Phenotypic and genotypic variability in four males with MECP2 gene sequence aberrations including a novel deletion. (medlineplus.gov)
  • Souyris et al reported that in both females and males with Klinefelter syndrome, substantial fractions of primary B lymphocytes, monocytes, and plasmacytoid dendritic cells express TLR7 on both X chromosomes, leading to greater immunoglobulin secretion. (medscape.com)
  • Mutagenic studies consisted of unscheduled DNA synthesis in human diploid WI-38 cells, mutation frequency in host mediated assays, sex linked recessive lethal mutation and loss of X or Y chromosomes in Drosophila melanogaster, spermhead abnormality in rats and mice, chromosomal aberrations in rat bone marrow, and rat dominant lethal experiments. (cdc.gov)
  • 3.3 Concept of Human Genome : nuclear genome, mitochondrial genome, Chromosome and chromosomal aberrations in man (Numerical and structural aberrations, point mutation), Satellite DNA. (souravsirclasses.com)
  • Like deletions, duplications can happen anywhere along the chromosome. (solarpoultry.com)
  • A post-natal karyotype and chromosomal SNP microarray revealed deletions of both terminal regions of the Y chromosome, consistent with the prenatal diagnosis of the ring Y chromosome. (juniperpublishers.com)
  • Chromosome 9 aberrations involving the terminal end of p arm, such as terminal p deletions or ring chromosomes have been reported to cause 46,XY DSD. (biomedcentral.com)
  • This consists of a failure in the chromosome pairs or the chromatids to separate in the first or second meiotic divisions or during mitosis. (solarpoultry.com)
  • of someones chromosomes (while a cell is in mitosis), cut them out and match them up using size, banding pattern and centromere position as guides. (solarpoultry.com)
  • Because of the instability of a ring Y chromosome during mitosis, a second monosomic cell line is often present in these patients [ 2 ]. (juniperpublishers.com)
  • This intricate phase, located within the larger mechanism of mitosis, is responsible for acting as a guarantor that each nascent cell obtains A precise set of chromosomes. (biologyideas.com)
  • By definition, anaphase is a phase of mitosis wherein the replicated chromosomes, known as sister chromatids, separate from one another and move toward opposite poles of the cell. (biologyideas.com)
  • Anaphase marks a pivotal stage in mitosis, crucially ensuring each resulting daughter cell inherits an accurate set of chromosomes. (biologyideas.com)
  • It has been shown above that crossovers between X chromosome segments inverted with respect to one another influence the orientation of the meiotic tetrads in such a way as to eliminate the single crossover chromatids, leaving a normal non-crossover one in the reduced egg nucleus. (caltech.edu)
  • We now recognize that, following DNA replication, the metaphase chromosome consists of two chromatids held together by a centromere and by cohesin. (biomedcentral.com)
  • Walter Sutton (left) and Theodor Boveri (right) independently developed the chromosome theory of inheritance in 1902. (wikipedia.org)
  • Aided by the rediscovery at the start of the 1900s of Gregor Mendel 's earlier work, Boveri was able to point out the connection between the rules of inheritance and the behaviour of the chromosomes. (wikipedia.org)
  • Cytoplasmic inheritance, sex-linked, sex-influenced and sex-limited characters. (chanakyamandal.org)
  • The risk of developing SLE is at least in part genetic, but it is a complex genetic illness with no clear mendelian pattern of inheritance. (medscape.com)
  • In 1959, these men with Klinefelter syndrome were discovered to have an extra X chromosome (genotype XXY) instead of the usual male sex complement (genotype XY). (medscape.com)
  • Structures like centromere, kinetochore, secondary constriction and chromosomal arms are not formed in prokaryotic chromosomes. (oracleias.org)
  • Eukaryotic chromosome contains centromere kinetochore and chromosomal arms. (oracleias.org)
  • [4] Before this happens, each chromosome is duplicated ( S phase ), and both copies are joined by a centromere , resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. (wikipedia.org)
  • Iso-chromosomes: A new type of chromo-some may arise from a break (i.e., a misdivision) at the centromere. (solarpoultry.com)
  • A 46,XY sex reversal syndrome is characterized by discordant genetic and phenotypic sex, leading to normal external female genitalia, undeveloped gonads and presence of Müllerian structures in an otherwise 46,XY individual. (biomedcentral.com)
  • Whether a human embryo develops as a male or a female is determined by the presence of the Y chromosome. (nih.gov)
  • 2) If the normal X's of such hyperploids carry the recessive gene for yellow, the flies are wild-type in appearance because of the presence of +y in the duplicating chromosome. (caltech.edu)
  • Assuming that plant height is controlled by a single gene, use genetic symbols to explain the F1 phenotype, and indicate the relationship between the two alleles (e.g., dominant, or recessive, or Éetc. (collepals.com)
  • The salivary gland chromosome technique has made it possible to demonstrate not only that these are inverted sections, but also that there are many different inversions present in wild populations inhabiting different geographical regions. (caltech.edu)
  • Each eukaryotic chromosome contains a linear DNA with two ends. (oracleias.org)
  • Eukaryotic chromosome contain many origin of replications and the genetic material will only replicate at the S phase of cell cycle. (oracleias.org)
  • Telomere is present in the tip of eukaryotic chromosome. (oracleias.org)
  • The most common chromosomal aberrations associated especially with severe oligo- and azoospermia are sex chromosome aneuploidies and chromosomal translocations. (virascience.com)
  • Trisomy 21, also referred to as Down's syndrome, is a chromosomal aberration characterized by the presence of an additional chromosome 21.Trisomy 21 is associated with a rate of incidence of 1:600 among newborns and is one of the most common chromosomal … However, they can also have detrimental effects. (solarpoultry.com)
  • Under ordinary conditions there is so little crossing over in the fourth chromosome of Drosophila melanogaster that the usual method of constructing a map is not practicable. (caltech.edu)
  • Genetic studies showed several years ago that the third chromosomes of wild strains of Drosophila pseudoobscura often carry suppressors of crossing-over. (caltech.edu)
  • In a series of papers, Serebrovsky (1930), Dubinin (1929), Agol (1930) and their colleagues have described an extremely interesting group of bristle-reducing mutant genes lying at the scute locus of the X-chromosome of Drosophila melanogaster. (caltech.edu)
  • In September, 1913, a wild female Drosophila of a stock from Liverpool, Nova Scotia, was crossed to a male bearing the second chromosome mutant characters vestigial and speck. (caltech.edu)
  • The first group includes papers describing structural changes of the chromosomes produced by LSD in vitro , ** in these experiments various concentrations of LSD are added to cultures of cells from human, animal, or plant tissues in a test-tube. (druglibrary.net)
  • In this case, possible clastogenicity is examined in an in vitro and in vivo chromosome aberration study and therefore not considered necessary in the Ames test. (europa.eu)
  • Moreover, a reliable in vitro study (Murie and Innes, 1997 K3 CSR) is available in which the potential of LAS Na to cause chromosomal aberrations in mammalian cells was examined. (europa.eu)
  • It is defined classically by a 47,XXY karyotype with variants that demonstrate additional X and Y chromosomes. (medscape.com)
  • Consequently, Genetic testing and counselling is indicated for infertile men with abnormal semen parameters with either abnormal karyotype or normal karyotype before applying assisted reproductive techniques. (ijfs.ir)
  • On karyotype, the presumptive ring Y chromosome was present in 29% of the cells and a single X chromosome was present in the other 71% of cells. (juniperpublishers.com)
  • The attached sheet shows the karyotype of four human individuals (A through D). Complete the following table to identify the sex, and the chromosomal aberration or name of the syndrome. (collepals.com)
  • Perchloroethylene caused spermhead abnormality in mice, positive responses in host mediated assay, and weak or borderline responses in tests for unscheduled DNA synthesis and bone marrow aberrations. (cdc.gov)
  • and (iv) induces chromosomal aberrations and sister chromatid exchange in mice in vivo. (who.int)
  • Amniocentesis is the most commonly used invasive method for prenatal diagnosis of genetic disorders. (ogscience.org)
  • The dystrophin gene is located on the short arm of chromosome X near the p21 locus and codes for the large protein Dp427, which contains 3685 amino acids. (medscape.com)
  • This indicates that the genetic distance between the Factor IX gene and the fra(X) locus is too great for Factor IX probes to be used alone for carrier detection in the fra(X) syndrome. (mcmaster.ca)
  • The higher risk of SLE in women and men with Klinefelter syndrome may be associated with enhanced expression of toll-like receptor 7 (TLR7), a key pathogenic factor in SLE that is encoded on an X chromosome locus. (medscape.com)
  • Therefore, we conducted a case study of a 46,XY female to better understand the genotypic and phenotypic characteristics related to 9p24.3 aberration and DMRT1 loss. (biomedcentral.com)
  • As the number of X chromosomes increases, somatic and cognitive development are more likely to be affected. (medscape.com)
  • These chromosomes exist in pairs in the somatic cells in contrast to their solo presence in germinal or sex cells , i.e. gametes . (biologyonline.com)
  • The review provides a brief account of the structure of somatic and meiotic chromosomes, stressing the high conservation of structure in plants and animals, with emphasis on aspects that require further research. (biomedcentral.com)
  • These studies reaffirmed that chromosome structure and behavior in somatic and germ cell divisions were common to all plants and animals. (biomedcentral.com)
  • Smokers produce sperm with the wrong number of chromosomes, a DNA error that leads to miscarriages and Down Syndrome . (susansmithjones.com)
  • As most people know, procreation depends on the fusion of two germ cells, sperm and oocytes, which transfers genetic and epigenetic information of the parents to the offspring. (kyoto-u.ac.jp)
  • We have localized an essential part of the sex-determining function to a portion of interval 1A, on the basis of the discovery of a female with a reciprocal Y;22 translocation and part of 1A deleted at the translocation breakpoint. (nih.gov)
  • The gene loci coding for each of the DAG complex proteins is located outside the X chromosomes. (medscape.com)
  • CGH array revealed a deletion around 1.25 Mb at 9p24.3 loci [arr 9p24.3(204,193-1,457,665)× 1] and three duplications around 13 Mb [9p24.3p22.3(1,477,660-14,506,754)× 3] near the breakage point that formed the ring chromosome 9. (biomedcentral.com)
  • Genome-wide association studies have identified more than 100 genetic loci for SLE susceptibility across populations, with most of the genetic risk shared across borders and ethnicities. (medscape.com)
  • In eukaryotes the genetic material is organized as distinct structural entities called chromosomes. (oracleias.org)
  • 22) * After my arrival in the United States, I participated in a major study concentrating on structural changes of the chromosomes in the white blood cells following LSD administration. (druglibrary.net)
  • The possibility of inducing structural changes in the chromosomes by exogenous agents such as radiation, viruses, and a variety of chemicals, has been a subject of great scientific interest for a long time. (druglibrary.net)
  • General designation for syndromes due to chromosomal aberrations, typically associated with mental … Thus, there are normally 23 pairs of chromosomes in the fertilized egg. (solarpoultry.com)
  • These chromosomes occur in pairs (22 pairs) and are 44 in number in human beings. (biologyonline.com)
  • The sequence of base pairs in DNA/RNA is thus the universal genetic code in all forms of life that descended from a common progenitor 4.5 billion years ago. (biomedcentral.com)
  • Because of the various life-threatening medical problems surrounding this condition, the majority of infants with trisomy 13 … 12.24, the two resultant telocentric chromosomes may open up to produce chromosomes with two identical arms (i.e., iso-chromosomes). (solarpoultry.com)
  • The switch from metaphase to anaphase is a critical event, powered by the Anaphase-Promoting Complex/Cyclosome (APC/C). Essentially, this is a signal within the cell stating that the chromosomes have been properly aligned on the metaphase plate, signifying their readiness for separation. (biologyideas.com)
  • If such deductions are to be of value, it is desirable that there be available a satisfactory arrangement of the species into some scheme of classification that can be taken as indicating their degree of genetic relationship. (caltech.edu)
  • Genetic toxicologists as experts should consider data quality and reliability, and give a critical review of all available information for sup- port of classification. (cdc.gov)
  • The 2016 World Health Organization (WHO) classification of lymphoid neoplasms incorporates genetic data, clinical features, cell morphology, and immunophenotype, all of which have important implications for disease prognosis and management. (msdmanuals.com)
  • METHODS: We retrospectively analyzed 785 cases of midtrimester prenatal genetic amniocentesis which were performed in the cytogenetics laboratory using in situ coverslip culture at Dong-A University Hospital from January 1995 to March 2003. (ogscience.org)
  • The future of molecular cytogenetics is likely to depend on a better knowledge of chromosome structure and function. (biomedcentral.com)
  • One of the purposes of this review is to encourage research into chromosome structure as this could help advance molecular cytogenetics. (biomedcentral.com)
  • The prokaryotic chromosome is comparatively shorter. (oracleias.org)
  • Prokaryotic chromosomes code for few proteins. (oracleias.org)
  • Due to the absence of the nucleus ,the prokaryotic chromosomes stay in direct contact with the cytoplasm. (oracleias.org)
  • Prokaryotic chromosome contains only a single origin of replication and can occur at any stage of life cycle. (oracleias.org)
  • Like many aspects of a drone's life, haploid susceptibility could be viewed as a sacrificial act, helping to sustain higher species fitness through a form of genetic cleansing. (americanbeejournal.com)
  • Phylogenomic studies using chromosome painting confirms the high conservation of DNA between even distantly related species [ 13 ]. (biomedcentral.com)
  • Anaphase, a fundamental step in the process of cell division, plays a crucial role in ensuring accurate genetic information transfer. (biologyideas.com)
  • Furthermore, we delve into the significant role of the mitotic spindle, the complex that serves as the catalyst for moving chromosomes during anaphase, and observe the consequential fallout in case of anaphase errors, putting emphasis on common mishaps like non-disjunction which could potentially trigger chromosomal disorders including cancer and Down syndrome. (biologyideas.com)
  • Anaphase holds vast importance in the division of cells and ensuring genetic continuity. (biologyideas.com)
  • In spite of the meticulous processes that normally ensure accurate chromosome separation, errors during anaphase can still occur, leading to chromosomal instability and disease. (biologyideas.com)
  • Thus, anaphase and its precise execution are crucial for maintaining genetic stability and cellular health. (biologyideas.com)
  • X chromosome inactivation is the the process by which most genes on one of the two X chromosomes in females are silenced epigenetically and randomly, and so fail to produce any product. (solarpoultry.com)
  • Be it for development, differentiation, stemness, or sex chromosome dosage compensation, stable, cell specific regulation of gene expression is essential for normal function ( 1 ). (aacrjournals.org)
  • Therefore, DMRT1 is suggested to have an important role in sex differentiation. (biomedcentral.com)
  • The frequency of a ring chromosome in clinically detectable conceptions is 1/25,000 however, the incidence of the ring Y chromosome is unknown [ 1 ]. (juniperpublishers.com)
  • Females, therefore, have fewer opportunities to propagate their genes, and are under strong selection to maximize their genetic contributions in other ways. (americanbeejournal.com)
  • In females, who have two copies of the X chromosome, one altered copy of the gene in each cell can lead to less severe features of the condition or may cause no signs or symptoms at all. (medlineplus.gov)
  • We are investigating the genetic and epigenetic mechanisms that determine the development of germ cells. (kyoto-u.ac.jp)
  • The mechanisms of transmission of both discontinuous and continuous characteristics across the generations were unknown before Mendel's laws were explained at the turn of the 20th Century by the behavior of chromosomes in germ cells [ 2 , 3 ]. (biomedcentral.com)
  • The result is an abnormal number of chromosomes. (solarpoultry.com)
  • chromosomal disorders It is caused due to absence or excess or abnormal arrangement of one or more chromosomes. (solarpoultry.com)
  • Some medical authorities assert that homosexuality is either the result of genetic problems (abnormal chromosome variations) or psychological aberrations. (christiancourier.com)
  • A chromosome is a long DNA molecule with part or all of the genetic material of an organism. (wikipedia.org)
  • Genetic causes have a considerable involvement in infertility. (virascience.com)
  • Presence of microdeletions can cause different disorders such as infertility, genetic diseases, neuropsychiatric disorders and testicular cancer. (cloudhealthlabs.com)
  • In trying to breed the perfect tomato plant (a diploid flowering plant), I have been carrying out some simple genetic experiments. (collepals.com)
  • Nonetheless, phenotype-genotype correlations suggest that two or more genetic elements in interval 1A may contribute to the sex-determining function of the Y chromosome. (nih.gov)
  • The X,t(Y;22) female lacks the ZFY gene but does not exhibit the complex phenotype known as Turner's syndrome, arguing against the hypothesis that ZFY is the Turner's syndrome gene on the Y chromosome. (nih.gov)
  • Variability of phenotype depends on the percentage of monosomic cells in different tissues and on the genetic material deleted during the formation of ring Y chromosome. (juniperpublishers.com)
  • Inclusion of other genes in the duplicated region, or inclusion of aberrations of genes at the duplication endpoints, may potentially affect the phenotype. (medscape.com)
  • The sex-determining function lies entirely in interval 1A, inasmuch as most XX individuals with descended testes and normal male external genitalia carry this small region of the Y chromosome. (nih.gov)