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.)Chromosome Fragility: Susceptibility of chromosomes to breakage leading to translocation; CHROMOSOME INVERSION; SEQUENCE DELETION; or other CHROMOSOME BREAKAGE related aberrations.Chromosomes: In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Chromosome Banding: 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.X Chromosome: The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.Chromosome Aberrations: Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.Chromosomes, Human, 6-12 and X: The medium-sized, submetacentric human chromosomes, called group C in the human chromosome classification. This group consists of chromosome pairs 6, 7, 8, 9, 10, 11, and 12 and the X chromosome.Chromosome Breakage: A type of chromosomal aberration involving DNA BREAKS. Chromosome breakage can result in CHROMOSOMAL TRANSLOCATION; CHROMOSOME INVERSION; or SEQUENCE DELETION.Sex Chromosomes: 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 16: A specific pair of GROUP E CHROMOSOMES of the human chromosome classification.Chromosomes, Human: Very long DNA molecules and associated proteins, HISTONES, and non-histone chromosomal proteins (CHROMOSOMAL PROTEINS, NON-HISTONE). Normally 46 chromosomes, including two sex chromosomes are found in the nucleus of human cells. They carry the hereditary information of the individual.Aphidicolin: An antiviral antibiotic produced by Cephalosporium aphidicola and other fungi. It inhibits the growth of eukaryotic cells and certain animal viruses by selectively inhibiting the cellular replication of DNA polymerase II or the viral-induced DNA polymerases. The drug may be useful for controlling excessive cell proliferation in patients with cancer, psoriasis or other dermatitis with little or no adverse effect upon non-multiplying cells.Chromosomes, Human, Pair 7: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Chromosomes, Human, Pair 1: A specific pair of human chromosomes in group A (CHROMOSOMES, HUMAN, 1-3) of the human chromosome classification.Genomic Instability: An increased tendency of the GENOME to acquire MUTATIONS when various processes involved in maintaining and replicating the genome are dysfunctional.DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Amyotrophic Lateral Sclerosis: A degenerative disorder affecting upper MOTOR NEURONS in the brain and lower motor neurons in the brain stem and SPINAL CORD. Disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. Clinical manifestations include progressive weakness, atrophy, FASCICULATION, hyperreflexia, DYSARTHRIA, dysphagia, and eventual paralysis of respiratory function. Pathologic features include the replacement of motor neurons with fibrous ASTROCYTES and atrophy of anterior SPINAL NERVE ROOTS and corticospinal tracts. (From Adams et al., Principles of Neurology, 6th ed, pp1089-94)DNA Repair: The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.Myotonic Dystrophy: Neuromuscular disorder characterized by PROGRESSIVE MUSCULAR ATROPHY; MYOTONIA, and various multisystem atrophies. Mild INTELLECTUAL DISABILITY may also occur. Abnormal TRINUCLEOTIDE REPEAT EXPANSION in the 3' UNTRANSLATED REGIONS of DMPK PROTEIN gene is associated with Myotonic Dystrophy 1. DNA REPEAT EXPANSION of zinc finger protein-9 gene intron is associated with Myotonic Dystrophy 2.Neuromuscular Diseases: A general term encompassing lower MOTOR NEURON DISEASE; PERIPHERAL NERVOUS SYSTEM DISEASES; and certain MUSCULAR DISEASES. Manifestations include MUSCLE WEAKNESS; FASCICULATION; muscle ATROPHY; SPASM; MYOKYMIA; MUSCLE HYPERTONIA, myalgias, and MUSCLE HYPOTONIA.Conflict (Psychology): The internal individual struggle resulting from incompatible or opposing needs, drives, or external and internal demands. In group interactions, competitive or opposing action of incompatibles: antagonistic state or action (as of divergent ideas, interests, or persons). (from Merriam-Webster's Collegiate Dictionary, 10th ed)Hepatitis, Infectious Canine: A contagious disease caused by canine adenovirus (ADENOVIRUSES, CANINE) infecting the LIVER, the EYE, the KIDNEY, and other organs in dogs, other canids, and bears. Symptoms include FEVER; EDEMA; VOMITING; and DIARRHEA.Workplace: Place or physical location of work or employment.Dog Diseases: Diseases of the domestic dog (Canis familiaris). This term does not include diseases of wild dogs, WOLVES; FOXES; and other Canidae for which the heading CARNIVORA is used.PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.BooksPublishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.MEDLINE: The premier bibliographic database of the NATIONAL LIBRARY OF MEDICINE. MEDLINE® (MEDLARS Online) is the primary subset of PUBMED and can be searched on NLM's Web site in PubMed or the NLM Gateway. MEDLINE references are indexed with MEDICAL SUBJECT HEADINGS (MeSH).Serial Publications: Publications in any medium issued in successive parts bearing numerical or chronological designations and intended to be continued indefinitely. (ALA Glossary of Library and Information Science, 1983, p203)Biological Science Disciplines: All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.AxisTeaching Materials: Instructional materials used in teaching.Pharmacology, Clinical: The branch of pharmacology that deals directly with the effectiveness and safety of drugs in humans.Competitive Behavior: The direct struggle between individuals for environmental necessities or for a common goal.Video Games: A form of interactive entertainment in which the player controls electronically generated images that appear on a video display screen. This includes video games played in the home on special machines or home computers, and those played in arcades.Spondylolisthesis: Forward displacement of a superior vertebral body over the vertebral body below.Physiology: The biological science concerned with the life-supporting properties, functions, and processes of living organisms or their parts.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.MedlinePlus: NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.Molecular Sequence Annotation: The addition of descriptive information about the function or structure of a molecular sequence to its MOLECULAR SEQUENCE DATA record.Botany: The study of the origin, structure, development, growth, function, genetics, and reproduction of plants.Triploidy: Polyploidy with three sets of chromosomes. Triploidy in humans are 69XXX, 69XXY, and 69XYY. It is associated with HOLOPROSENCEPHALY; ABNORMALITIES, MULTIPLE; PARTIAL HYDATIDIFORM MOLE; and MISCARRAGES.Cimicidae: A family of wingless, blood-sucking insects of the suborder HETEROPTERA, including the bedbugs and related forms. Cimex (BEDBUGS), Heamatosiphon, and Oeciacus are medically important genera. (From Dorland, 28th ed)Stevens-Johnson Syndrome: Rare cutaneous eruption characterized by extensive KERATINOCYTE apoptosis resulting in skin detachment with mucosal involvement. It is often provoked by the use of drugs (e.g., antibiotics and anticonvulsants) or associated with PNEUMONIA, MYCOPLASMA. It is considered a continuum of Toxic Epidermal Necrolysis.Desulfovibrio: A genus of gram-negative, anaerobic, rod-shaped bacteria capable of reducing sulfur compounds to hydrogen sulfide. Organisms are isolated from anaerobic mud of fresh and salt water, animal intestines, manure, and feces.Peptide Nucleic Acids: DNA analogs containing neutral amide backbone linkages composed of aminoethyl glycine units instead of the usual phosphodiester linkage of deoxyribose groups. Peptide nucleic acids have high biological stability and higher affinity for complementary DNA or RNA sequences than analogous DNA oligomers.Plants, Edible: An organism of the vegetable kingdom suitable by nature for use as a food, especially by human beings. Not all parts of any given plant are edible but all parts of edible plants have been known to figure as raw or cooked food: leaves, roots, tubers, stems, seeds, buds, fruits, and flowers. The most commonly edible parts of plants are FRUIT, usually sweet, fleshy, and succulent. Most edible plants are commonly cultivated for their nutritional value and are referred to as VEGETABLES.

How many tumor suppressor genes are involved in human lung carcinogenesis? (1/223)

To date, only a limited number of tumor suppressor genes have been identified as being inactivated in lung cancer. The p53 and RB genes are frequently inactivated by genetic alterations such as chromosomal deletions and loss-of-function mutations, while the p16 gene is inactivated not only by genetic alterations but also by transcriptional silencing due to hypermethylation. Recently, it was shown that the FHIT gene encompassing the chromosomal fragile site, FRA3B, is also inactivated in a large proportion of lung cancers. Several lines of evidence indicate the presence of additional tumor suppressor genes involved in lung carcinogenesis. Lung cancer cells often show deletions at multiple chromosomal regions, and deletion mapping studies have defined more than 30 regions dispersed on 21 different chromosome arms as candidate tumor suppressor loci. Several chromosomal regions hypermethylated in lung cancer cells and a number of chromosomal fragile sites have been mapped to the regions deleted in lung cancer. These chromosomal loci can harbor unknown tumor suppressor genes inactivated in lung cancer. Studies on the inherited susceptibility to lung cancer in mice have also indicated the presence of additional tumor suppressor genes for lung cancer. Further analyses of these loci should elucidate how many tumor suppressor genes are involved in human lung carcinogenesis. Molecular and functional analyses of those genes will make it possible to fully understand the molecular mechanism of lung carcinogenesis.  (+info)

Type and frequency of chromosome aberrations in 781 couples undergoing intracytoplasmic sperm injection. (2/223)

Cytogenetic investigations were performed in 781 couples prior to intracytoplasmic sperm injection (ICSI) because of severe male infertility or fertilization failures in previous in-vitro fertilization attempts. Out of these 1562 patients, 1012 had a normal karyotype without any aberrations (64.8%), 204 patients had an abnormal karyotypes (13.1%). These chromosome aberrations included constitutional aberrations (4.4%), fragile sites of autosomes (3.0%), low level mosaicism of sex chromosomes (4.0%) and secondary structural chromosome aberrations (4.2%). Combinations of different types of abnormalities were stated. Another 346 patients (22.1%) showed single cell aberrations; the significance of these is unclear at the moment. Constitutional chromosome aberrations were detected in 69 patients. The following chromosome aberrations were observed: 35 sex chromosomal aberrations (comprising hyperploidies of X or Y chromosomes, mosaicisms and derivative X and Y chromosomes), 34 autosomal aberrations including 14 reciprocal translocations, five Robertsonian translocations, six inversions, one marker chromosome, one trisomy 18 mosaicism and seven other structural aberrations. Three autosomal regions showed fragile sites: 6q13 in 2.9% of the patients, 17p12 and 10q24 in 0.05% each. In conclusion, our data show that a high number of infertile couples in an ICSI programme are affected by chromosome aberrations which occur in both sexes. It is suggested that a chromosomal analysis should be performed on both partners before ICSI treatment is initiated.  (+info)

CGG/CCG repeats exhibit orientation-dependent instability and orientation-independent fragility in Saccharomyces cerevisiae. (3/223)

An expansion to >200 CGG/CCG repeats (hereafter called CGG) in the 5' region of the FMR1 gene causes fragile X syndrome, and this locus becomes a folate-sensitive fragile site. We used Saccharomyces cerevisiae as a model system to study the stability and fragility of CGG repeats. Tracts of (CGG)(81)and (CGG)(160)were integrated onto a yeast chromosome in both orientations relative to the nearest replication origin. Tracts of this length are pre-mutation alleles in humans, with a high probability of expansion in future generations. The CGG tracts in yeast colonies showed a length-dependent instability with longer tracts being more prone to contraction than shorter tracts. In addition, there was an orientation bias for tract stability with tracts having fewer contractions when the CCG strand was the template for lagging strand synthesis. Expansions of the CGG tracts also occurred in an orientation-dependent manner, although at a lower frequency than contractions. To determine whether CGG tracts are fragile sites in yeast, the CGG tracts were flanked by direct repeats, and the rate of recombination between the repeats determined. Strains carrying the (CGG)(160)tract in either orientation had a large increase in their rate of recombination compared with a no-tract control strain. Because this increase was dependent on genes involved in double-strand break repair, recombination was likely to be initiated by CGG tract-induced breakage between the direct repeats. The observation of orientation-dependent instability and orientation-independent fragility suggests that at least some aspects of their underlying mechanisms are different.  (+info)

Chromosomal fragile site FRA16D and DNA instability in cancer. (4/223)

It has been proposed that common aphidicolin-inducible fragile sites, in general, predispose to specific chromosomal breakage associated with deletion, amplification, and/or translocation in certain forms of cancer. Although this appears to be the case for the fragile site FRA3B and may be the case for FRA7G, it is not yet clear whether this association is a general property of this class of fragile site. The major aim of the present study was to determine whether the FRA16D chromosomal fragile site locus has a role to play in predisposing DNA sequences within and adjacent to the fragile site to DNA instability (such as deletion or translocation), which could lead to or be associated with neoplasia. We report the localization of FRA16D within a contig of cloned DNA and demonstrate that this fragile site coincides with a region of homozygous deletion in a gastric adenocarcinoma cell line and is bracketed by translocation breakpoints in multiple myeloma, as reported previously (Chesi, M., et al., Blood, 91: 4457-4463, 1998). Therefore, given similar findings at the FRA3B and FRA7G fragile sites, it is likely that common aphidicolin-inducible fragile sites exhibit the general property of localized DNA instability in cancer cells.  (+info)

A 700-kb physical map of a region of 16q23.2 homozygously deleted in multiple cancers and spanning the common fragile site FRA16D. (5/223)

We have identified a >600-kb region at 16q23.2 that is homozygously deleted from malignant ovarian ascites using representational difference analysis. Overlapping homozygous deletions were also observed in the colon carcinoma cell line HCT116 and a xenograft established from the small cell lung cancer cell line WX330. This region coincides with that described previously by others as showing loss of heterozygosity in prostate and breast cancers (C. Li et al., Genes Chromosomes Cancer, 24: 175-182, 1999; A. Latil et al., Cancer Res., 57: 1058-1062, 1997; K. Driouch et al., Genes Chromosomes Cancer, 19: 185-191, 1997; A. Iida et al., Br. J. Cancer, 75: 264-267, 1997). In addition, the minimally deleted region spans the common fragile site FRA16D. We have constructed a 700-kb physical map encompassing the deleted region. By fluorescence in situ hybridization of aphidicolin-induced metaphase chromosomes, we have preliminary data to suggest that P1-derived bacterial artificial chromosome clones from the contig lie on both sides of FRA16D. This is confirmed by extensive fluorescence in situ hybridization analysis of the region reported in the accompanying article (M. Mangelsdorf et al., Cancer Res., 60: 1683-1689, 2000) and is consistent with an involvement of this common fragile site in the loss of 16q23.2 material in various cancer types. The minimally deleted region of approximately 210 kb has been characterized using our own markers and public domain markers. Eleven distinct expressed sequences mapped to the region, providing a basis for identifying the predicted tumor suppressor gene in this region.  (+info)

Definitive functional evidence for a tumor suppressor gene on human chromosome 7q31.1 neighboring the Fra7G site. (6/223)

We have previously shown that loss of heterozygosity (LOH) on human chromosome (hchr) 7 at q31.1 is common in a variety of tumors of epithelial origin. Frequent LOH of a specific chromosomal marker is indicative of a closely linked tumor suppressor gene (TSG). However, recent reports have also indicated that such a high frequency of LOH could be due to the presence in this region of the second most common aphidicolin-inducible fragile site in the human genome (Fra7G). To address this controversy, we introduced single copies of hchr7 or hchr12 into a highly aggressive human prostate carcinoma cell line (PC3) by microcell-mediated transfer. The tumorigenicity of six clones of PC3/hchr7 hybrids and three clones of PCRhchr12 hybrids, obtained in four separate fusion experiments, were studied in BALB/c nude mice. All but one of the PC3/hchr7 hybrids increased tumor latency by at least twofold, whereas none of the PC3/hchr12 hybrids delayed tumor onset. No differences in the in vitro growth rate were observed among any of the cell lines assayed (parental and hybrids) suggesting that the observed tumor suppression was due to factors other than cell cycle regulation. Deletion mapping of the PC3/hchr7 tumors obtained after reversion to the malignant phenotype revealed a common region of loss centred around 7q31.1, supporting the TSG hypothesis. The smallest commonly deleted region was approximately 1.5 Mb in size and flanked by the markers D7S486 and D7S655.  (+info)

Co-localisation of CCG repeats and chromosome deletion breakpoints in Jacobsen syndrome: evidence for a common mechanism of chromosome breakage. (7/223)

Folate-sensitive fragile sites are associated with the expansion and hypermethylation of CCG-repeats. The fragile site in 11q23.3, FRA11B, has been shown to cause chromosome deletions in vivo, its expression being associated with Jacobsen (11q-) syndrome. However, the majority of Jacobsen deletions are distal to FRA11B and are not related to its expression. To test the hypothesis that other unidentified fragile sites might be located in 11q23.3-24 and may cause these deletions, we have identified and characterised CCG-trinucleotide repeats within a 40 Mb YAC contig spanning distal chromosome 11q. Only eight CCG-repeats were identified within the entire YAC contig (not including FRA11B ), six of which map to the region of 11q23.3-24 that includes Jacobsen deletions. We have previously collated the deletion mapping data of 24 Jacobsen patients with the physical map of chromosome 11q, and accurately localised six breakpoints to short intervals corresponding to individual YAC clones. We now show that in each of these cases, YAC clones found to contain a deletion breakpoint also contain a CCG-repeat. The improved analysis of one of these deletions, together with those of several new Jacobsen cases, further strengthens this association by localising five breakpoints to individual PAC clones containing CCG-repeats. These data provide strong evidence for the non-random clustering of chromosome deletion breakpoints with CCG-repeats, and suggests that they may play an important role in a common mechanism of chromosome breakage.  (+info)

The expression of common fragile sites in peripheral blood lymphocytes of breast and colorectal cancer patients with aphidicolin. (8/223)

The frequency and distribution of aphidicolin induced common fragile sites was evaluated on chromosomes of peripheral blood lymphocytes in 10 breast and 10 colorectal cancer patients, and 10 healthy controls to determine correlation between specific fragile sites and cancer breakpoints. Fifty complete metaphases were screened from each culture and the results were evaluated by Student's t-test. The total number of fragile sites was found as 933 in breast cancer patients, 950 in colorectal cancer patients and 501 in control group. Both the number of aberrations per cell and number of aberrations per damaged cell were significantly higher in the patient groups. These findings indicate that genetic instability in the breast and colorectal cancer patients increased and fragile sites may play a critical role in the pathogenesis of breast and colorectal cancer.  (+info)

  • Linear order of new and established DNA markers around the fragile site at Xq27.3. (
  • So far, no microdissection markers derived from Xq28 material have been found, thus allowing a rapid screening for clones surrounding the fragile site by their presence in a somatic cell hybrid containing Xq27.2-Xqter. (
  • A total of 43 new DNA markers from Xq27 have been sublocalized within this chromosome band. (
  • Of these new DNA markers, 5 lie in an interval defined as containing the fragile X region. (
  • Azzalin CM, Reichenbach P, Khoriauli L, Giulotto E, Lingner J (2007) Telomeric repeat containing RNA and RNA surveillance factors at mammalian chromosome ends. (
  • The FHIT gene, spanning the chromosome 3p14.2 fragile site and renal carcinoma-associated t(3;8) breakpoint, is abnormal in digestive tract cancers. (
  • The FHIT locus is composed of ten exons distributed over at least 500 kb, with three 5' untranslated exons centromeric to the renal carcinoma-associated 3p14.2 breakpoint, the remaining exons telomeric to this translocation breakpoint, and exon 5 within the homozygously deleted fragile region. (
  • Since DNA sequence search shows that the FHIT gene has the E2F-1 recognition site in 5 ′ region, which regulates cell cycle, we tested the effect of E2F-1 overexpression in tumor cells. (
  • Reporter assay showed that the E2F-1 site in FHIT 5 ′ region was involved in the down-stream transcription after exogenous E2F-1 introduction. (
  • Chromatin immunoprecipitation detected exogenous E2F-1 binding to the recognition site in FHIT 5 ′ region. (
  • The role of fragile histidine triad ( fhit ) gene in the etiology of cancer is a relatively recent area of research. (
  • suggesting that the alteration of the fhit gene through damage to the associated fragile region by carcinogens may contribute in a large part to the pathophysiology of cancer. (
  • Fragile gene product, Fhit, in oxidative and replicative stress responses. (
  • Restoration of fragile histidine triad (FHIT) expression induces apoptosis and suppresses tumorigenicity in breast cancer cell lines. (
  • Restoration of fragile histidine triad (FHIT) expression induces apoptosis and suppresses tumorigenicity in lung and cervical cancer cell lines. (
  • Using such images, complete genomic sets of chromosomes can be classified ac. (
  • Structural (large scale abnormalities in genomic sequence of individual chromosomes). (
  • Inversions (top panel, right side) are where the normal order of genomic material within a chromosome is altered by the abnormal repair of chromosomal breakpoints (block arrows and dotted lines). (
  • All cases showed either loss or gain of whole chromosomes or segments of chromosome(s) with variable genomic sizes. (
  • Both of these genomic structures coincide with breakpoints in the genus Mus , suggesting that the accumulation of a large number of repeats in the centromeric region may contribute to the high level of chromosome repatterning observed in this group. (
  • Using repeat primed PCR (RP-PCR) in conjunction with a high-sensitivity pulsed-field capillary electrophoresis fragment analyzer (FEMTO-Pulse, Agilent, Santa Clara, CA) (RP-FEMTO hereafter), we successfully determined sequence content of large expansion repeats in genomic DNA of SCA10 patients and transformed yeast artificial chromosomes containing SCA10 repeats. (
  • After chromosome segregation in mitosis, the light pink cell remains heterozygous at all SNPs, while the red cell is homozygous for the YJM789 form of all SNPs distal to the invasion site. (
  • The SMC proteins were initially identified through genetic studies of chromosome segregation in Saccharomyces cerevisiae [ 13 ]. (
  • Huebner K, Druck T, Croce CM, Thiesen HJ (1991) Twenty seven non overlapping zinc finger cDNAs from human T cells map to nine different chromosomes with apparent clustering. (
  • Transmission electron micrographs of whole metaphase chromosomes isolated from Chinese Hamster Ovary (CHO) cells showing the characteristic paired chromatids and centromeric constrictions. (
  • The work begins with a look at historical themes, such as the analysis of metaphase chromosomes using microscopy and staining techniques, advances in which provided our first broad glimpse into the genetic anatomy of a malignant cell. (
  • These structures represent chromosomes that are missing the genetic material beyond that centromere. (
  • isochromosome which is a chromosome that contains the same genetic material on both arms. (
  • They believe the size of an area where X and Y genetic information mingle or recombine can serve as a strong clue that a species is at risk of losing the Y chromosome during sperm production. (
  • Traditionally, scientists have explained the loss by saying that the Y chromosome must not contain enough important genetic information and so it is dispensable. (
  • These chromosomes consist of genetic material (DNA) needed for the production of proteins, which lead to growth, development, and physical/intellectual characteristics. (
  • The analyses suggest that chromosome breakage within RSZs requires the actions of the evolutionarily conserved type II topoisomerase and condensin complex. (
  • Recently, in the WWOX (WW domain containing oxidoreductase), a candidate tumor suppressor gene, chromosome 16q23.3-24.1 was isolated. (
  • Nucleolar expansion due to abnormal increases in polyamines could disrupt nearby chromatin, such as the inactive X chromosome, leading to expression of previously sequestered DNA. (
  • In the hypothesis it was proposed that enlargement of the nucleolus in response to cellular stress could disrupt neighboring chromatin, such as the inactive X chromosome. (
  • Bacterial Artificial Chromosomes, Second Edition expands upon the previous edition with current, detailed methods developed for working with BACs. (
  • Authoritative and cutting-edge, Bacterial Artificial Chromosomes, Second Edition seeks to aid scientists in advancing their research using these exciting BAC techniques and strategies. (
  • This analysis revealed a high level of chromosome breakpoint conservation between Rattus and Peromyscus and indicated that the chromosomes of Mus are highly derived. (
  • In all diploids, BIR that is initiated by a lesion on the chromosome III homolog carrying the fragile site and in which invasion of the opposite homolog occurs at a location centromere-proximal to the marker gene ( SUP4-o or ADE2 ) will produce a sectored colony. (
  • telocentrics which are chromosomes that have a terminal centromere. (
  • MGR was applied using 107 chromosome homologies between Mus, Rattus, Peromyscus, the muroid sister taxon Cricetulus griseus, and Sciurus carolinensis as a non-Muroidea outgroup, with specific attention paid to breakpoint reuse and centromere evolution. (
  • If the inversions include the centromere of the chromosome they are called pericentric, if not, paracentric. (
  • High-resolution GTG-banded karyotype showed lack of centromeric constriction in some chromosomes, premature centromere separation in others, and repulsion of the heterochromatin regions. (
  • (13) , using two chromosome 10q markers ( D10S185 and D10S212 ), identified LOH in 1 of 19 (5.3%) benign, 4 of 21 (19.0%) atypical, and 5 of 9 (55.6%) malignant tumors. (
  • Azzalin CM, Reichenbach P, Khoriauli L, Giulotto E, Lingner J (2007) Telomeric repeat containing RNA and RNA surveillance factors at mammalian chromosome ends. (
  • In addition to these conditions, more than one pair of homologous chromosomes may be involved. (
  • The most accurate repair mechanism is based on homologous recombination (HR), in which single strands generated next to the break seek an intact replica which is copied into the broken site. (