Showing papers on "Chromosome 22 published in 1976"
TL;DR: Radiolabeled reiterated DNA specific for the human Y chromosome has been obtained by extensive reassociations between [3H]DNA prepared from men and excess DNA from women.
Abstract: Radiolabeled reiterated DNA specific for the human Y chromosome has been obtained by extensive reassociations between [3H]DNA prepared from men and excess DNA from women. These highly purifed labeled sequences reassociate only with DNA from individuals with a Y chromosome. The percentage of Y-chromosome-specific DNA isolated from individuals with differing numbers of Y chromosomes is a function of the number of chromosomes present. The purifed Y-chromosome-specific sequences may represent between 7 and 11 percent of the human Y chromosome.
102 citations
TL;DR: Findings not only confirm the assignment of the AK-1 locus to chromosome 9 made previously in somatic cell hybrids, but suggest a more precise assignment to region 9q33→qter.
Abstract: Quantitative red cell adenylate kinase (AK-1) assay has been used in 8 patients with partial duplication or deletion of chromosome 9 in an attempt to find the precise intrachromosomal location of the structural gene locus. All regions of chromosome 9 are represented in abnormal dosage in at least one patient. A 43% increase in AK-1 activity was found to be associated with duplication of the terminal band of the long arm of chromosome 9. Duplication of all other parts of chromosome 9 were associated with normal enzyme activity. These findings not only confirm the assignment of the AK-1 locus to chromosome 9 made previously in somatic cell hybrids, but suggest a more precise assignment to region 9q33→qter. This places the ABO: Np-1: AK-1 linkage group at the distal end of the long arm of chromosome 9.
102 citations
TL;DR: A large fraction of the constitutive heterochromatin of this species is present in the centromere region of the X + 3 chromosome and in the Y chromosome; these two regions possess similar amounts of DNA and therefore sort together.
Abstract: Metaphase chromosomes were isolated from a male Indian muntjac cell line, were stained with ethidium bromide and were analyzed by flow microfluorometry to establish a deoxyribonucleic acid (DNA)-based karyotype. Five major peaks were evident on the chromosomal DNA distribution corresponding to the five chromosome types in this species. The amount of DNA in each chromosome was confirmed by cytophotometric measurements of intact metaphase spreads. The five chromosome types were separated by flow sorting at rates up to several hundred chromosomes per second. The sorted chromosomes were identified by morphology and by Giemsa banding patterns. The autosomes, Numbers 1, 2 and 3, and the X + 3 composite chromosome were separated with a high degree of purity (9O� ). The centromere region of the X + 3 chromosome was fragile to mechanical shearing, and during isolation a small proportion of these chromosomes broke into four segments: the bong arm, the short arm, the short arm plus centromere and the centremere region. A large fraction of the constitutive heteroehromatin of this species is present in the centromere region of the X + 3 chromosome and in the Y chromosome; these two regions possess similar amounts of DNA and therefore sort together. Chromosome flow sorting is rapid, reproducible and precise; it allows the collection of microgram quantities of purified chromosomes.
61 citations
TL;DR: Localization of chromosome breaks in human chromosomes was analyzed in 264 peripheral lymphocyte cultures and found that three hundred and sixty-nine chromosome breaks could be exactly localized to a chromosome band or region of the Paris Conference nomenclature.
Abstract: Localization of chromosome breaks in human chromosomes was analyzed in 264 peripheral lymphocyte cultures. Three hundred and sixty-nine chromosome breaks could be exactly localized to a chromosome band or region of the Paris Conference nomenclature. The distribution of breaks in the chromosome regions was found to be nonrandom. Chromosome 3 alone had 23% of the breaks and region 3p2 had 13% of the total breaks. Some other chromosome regions, such as 5p1, 9q1, 14q2, and 16q2 also displayed clustering of breaks. Sex chromosomes had less breaks than expected. Spontaneous chromosome breaks were almost exclusively located in the lightly stained G bands.
47 citations
TL;DR: In situ hybridization of 3H-labelled ribosomal RNA to the chromosomes of rat bone marrow cells revealed that clusters of Ribosomal cistrons (rDNA) are located in the secondary constrictions of chromosomes No. 3 and 12 and near the centromere of chromosome No. 11, both associated with the late DNA-replicating regions.
Abstract: In situ hybridization of 3H-labelled ribosomal RNA to the chromosomes of rat bone marrow cells revealed that clusters of ribosomal cistrons (rDNA) are located in the secondary constrictions of chromosomes No. 3 and 12 and near the centromere of chromosome No. 11, both associated with the late DNA-replicating regions. They were not found in Nos. 1, 2, 13, 19, 20, and the Y chromosome.
44 citations
Journal Article•
TL;DR: No common marker for human melanoma was found, but in 6 of the 8 cultures the most frequently found marker was formed by a brightly banded chromatid addition, which was found in all metaphases from 2 different metastases.
Abstract: Since individual chromosomes can be accurately identified by new banding techniques, atebrin fluorescence was used for chromosome analysis in six cell lines and two primary outgrowths derived from human malignant melanoma. Gross aneuploidy was seen in all specimens, but each culture contained at least 1 distinctive marker chromosome specific for that cell line in 87 to 100% of metaphases. One of the primary explants contained a marker that was demonstrable in fresh tissue and persisted through 2 weeks of culture. The same marker was found in all metaphases from 2 different metastases, but skin fibroblasts from the same patient had a normal chromosome complement.
No common marker for human melanoma was found, but in 6 of the 8 cultures the most frequently found marker was formed by a brightly banded chromatid addition. Relative polysomy for Chromosome 7 was found in 7 of the 8 cultures and, for Chromosome 22, in 5 of the 8 cultures. The frequency of polysomy of Chromosomes 7 and 22 was significant at the 5% level.
42 citations
TL;DR: It is suggested that, during the transition from sperm head to mature pronucleus, repair of breaks and chromosome replication are two processes that occur in overlapping time intervals and it is therefore possible for chromosome breaks induced in mature sperm to give rise to chromosome and chromatid rearrangements.
Abstract: Drosophila melanogaster males with marked X and Y chromosomes were irradiated, and mature sperm sampled by mating the males to females carrying attached-X chromosomes. Induced loss and partial loss of the paternal sex chromosomes was studied. F 1 females were scored according to their phenotype, and transmitted fragments were analyzed genetically. Half of the exceptional F 1 females could be scored as “partial losses”. Of the apparent total loss exceptions, which were tested, half were carrying detectable fragments. 21% of the transmissible fragments were carrying a duplication of a paternal chromosome tip. This frequency is an under-estimate because only 6 of the 10 chromosome tips were marked in such a way that duplications could be detected. In addition, the markers used were located near, but not at, the chromosome ends. These data are interpreted as indicating that a high proportion of the chromosome loss and partial loss, induced by irradiation of mature sperm, is a consequence of chromatid rearrangements arising from chromosome breaks which stay open until replication. It is suggested that, during the transition from sperm head to mature pronucleus, repair of breaks and chromosome replication are two processes that occur in overlapping time intervals. It is therefore possible for chromosome breaks induced in mature sperm to give rise to chromosome and chromatid rearrangements.
37 citations
TL;DR: The marked inversion technique was used, and 38 major autosome sets of Drosophila melanogaster were extracted from populations of Jugoslavia, Taiwan and Japan as discussed by the authors.
Abstract: 1 (1) The marked inversion technique was used, and 38 major autosome sets of Drosophila melanogaster were extracted from populations of Jugoslavia, Taiwan and Japan Spontaneous mutations were allowed to accumulate on the major chromosomes for 25 generations Then the second chromosomes were tested to determine whether or not they were associated with such known mutator factors as the male crossing-over factor, SD, and the extrachromosomal element delta Chromosome mutations were examined by salivary gland chromosome analysis, and viability mutations were done by the marked autosomal translocation method 2 (2) In 8 out of 38 major autosome lines, 5 inversions occurred in the second chromosomes, 4 inversions in the third chromosomes, and 1 reciprocal translocation between the second and the third chromosomes Chromosome mutation rates were, therefore, 00063 per second chromosome per generation and 00053 per third chromosome per generation Since there was no significant difference in the rates, chromosome mutations seem to be occurring approximately equally in both major autosomes 3 (3) Lethal mutation rates were estimated to be 00097 per major autosome per generation 4 (4) Twenty-four second chromosome lines out of 37 demonstrated male crossing-over among the cinnabar and brown interval; the average frequencies were 00031 for all lines and 00034 when non-recombination lines were excluded 5 (5) One second chromosome exhibited delta retaining ability (ID), but no second chromosome carried SD
29 citations
TL;DR: A male infant with a partial trisomy 18 and a 46,XY, --21, t(18;21)(18qter replaced by 18q12::21 p13 replaced by 21 qter) chromosome complement is described.
Abstract: A male infant with a partial trisomy 18 and a 46,XY, --21, t(18;21)(18qter replaced by 18q12::21 p13 replaced by 21 qter) chromosome complement is described. The translocation chromosome is of special interest because it includes the satellites of chromosome 21. This was shown by differential satellite staining with the ammoniacal-silver technique.
26 citations
TL;DR: Trisomy-22 was confirmed with both Q-and G-banding in two sibs as mentioned in this paper and was interpreted as a product of a pericentric inversion on the basis of general length, arm ratio (1.4), and anomalous satellite association frequency.
Abstract: Trisomy-22 was confirmed with both Q- and G-banding in two sibs. Growth and mental retardation plus various dysmorphic features of this syndrome are described and compared with previous reports. Cytogenetic studies reveal a morphologically atypical No. 22 in cells of the phenotypically normal mother (46,XX) and in both affected children. The variant G chromosome is identified as No. 22 by Q- and G-banding and is interpreted as a product of a pericentric inversion on the basis of general length, arm ratio (1.4), and anomalous satellite association frequency. Repeated nondisjunction for No. 22 is considered to have resulted from asynapsis caused by interference of an inversion loop configuration which, though short, comprised a major part of chromosome 22.
25 citations
TL;DR: G-banding study revealed that the abnormal chromosome was produced as a result of fusion involving telomeric ends of long arms of 2 intact X chromosomes, bearing 2 C-banded areas; one around the centromere and the other at the distal end of the long arm.
Abstract: Cytological studies have been presented from a 15-year-old girl with short stature and failure of puberty. Buccal mucosa preparations revealed X-chromatin mass approximately double in size of that of a normal female. Leukocyte metaphases suggested a two cell line composition of the patient. One population of cells conformed with 45,X chromosome distribution. The chromosome complement of her other cell line had a modal number of 46. In this cell line a "C" chromosome was replaced by an exceptionally large submetacentric chromosome. This abnormal element exhibited late DNA replicating pattern. G-banding study revealed that the abnormal chromosome was produced as a result of fusion involving telomeric ends of long arms of 2 intact X chromosomes. This translocation X was bearing 2 C-banded areas; one around the centromere and the other at the distal end of the long arm. The distal C-band area did not show any evidence for centromeric function. It appears that a centromere becomes latent in the presence of another centromere in a translocation bearing 2 total chromosomes. Such a change of state in the additional centromere is vital for the stability of the translocation chromosome.
TL;DR: It is concluded that the rearrangement is of ancient origin and that it has been maintained in the populations of Pongo as a balanced polymorphism.
Abstract: A rearranged chromosome 9 was found in 12 of 23 specimens of orangutan, 4 of Bornean and 8 of Sumatran origin. Nine animals were heterozygous, and 3 were homozygous carriers for the variant chromosome
TL;DR: Chromosome counts were made on 105 spermatogonial and diakinesis cells prepared from testicular tissue taken from 10 hybrid cockerels.
Abstract: 1. Chromosome counts were made on 105 spermatogonial and diakinesis cells prepared from testicular tissue taken from 10 hybrid cockerels. 2. The modal numbers for the diploid chromosome and haploid chromosome complements were 78 and 39 respectively.
TL;DR: The absence of leukaemia or haematological disorder in members of this family suggests that the critical genetic site on chromosome 22 concerned with abnormal myeloid cell proliferation in human leukaukaemia is contained in the 22q12 band.
Abstract: A man and two of his three children carried an abnormally short chromosome 22 resembling the Philadelphia chromosome (Ph1). Giemsa banding showed that the abnormal chromosome resulted from a translocation t(11;22) (q25;q13). The breakpoint on chromosome 22 was at the q12/q13 band interface compared with the breakpoint of Ph1 at the q11/q12 band interface. The absence of leukaemia or haematological disorder in members of this family suggests that the critical genetic site on chromosome 22 concerned with abnormal myeloid cell proliferation in human leukaemia is contained in the 22q12 band.
TL;DR: The levels of DNA complementary to rRNA (normal in the father who had 10 NOR and increased in the proposita who had 11 NOR) confirmed the interpretation of the rearrangement.
Abstract: A malformed female infant was found to have a 46,XX complement with a chromosome 8 shorter than normal with a secondary constriction and satellites on the short arm. Chromosome studies on the clinically normal father showed a balanced translocation between chromosome 8 and 13, i.e., 46,XY,t(8;13) (p21 p12). The proposita, carrier of the unbalanced form of the translocation, resulted partially monosomic for short arm of chromosome 8 (8p-) and partially trisomic for short arm of chromosome 13. The levels of DNA complementary to rRNA (normal in the father who had 10 NOR and increased in the proposita who had 11 NOR) confirmed our interpretation of the rearrangement.
01 Jan 1976
TL;DR: The objective of the present paper is to review current knowledge of the nucleotype in plants, to point out its significance for understanding plant evolution, and to suggest the most promising lines of research for increasing the understanding of the role of theucleotype in evolution.
Abstract: The past ten years have seen a remarkable rejuvenation in chromosome cytology. Cytologists are justified in distinguishing between the Old Karyology, which was concerned chiefly with chromosomes as taxonomic markers and with chromosome changes that influence genetic systems through their effects on linkage and recombination, and the New Karyology, which has a much broader base. Chromosomes are now recognized to be not only the carriers of genes in a linear sequence, but simultaneously they are highly complex organelles that contain many diverse mechanisms for controlling cellular proliferation, cell enlargement, and the differential action of genes during development. Some of these mechanisms are based upon the diverse nature of DNA with respect to both structure and function, while others, perhaps the majority of them, reside in the diverse proteins that are complexed with DNA to form the chromatin of chromosomes. These include both the histones, which are associated with the condensation of chromatin and nonspecific repression of DNA transcription (Arbuzova et al., 1968), and a much larger and more diverse assemblage of acidic proteins that perform a variety of functions, including specific activation of transcription (Cameron and Jeter, 1974; Stein et al., 1975ab). Consequently, a new concept that is highly relevant to evolutionists as well as to biologists in general is that of the nucleotype (Bennett, 1972, 1974). This includes not only the genic DNA, but in addition the entire battery of control systems that are built into the nucleus of eukaryote cells. The objective of the present paper is to review current knowledge of the nucleotype in plants, to point out its significance for understanding plant evolution, and to suggest the most promising lines of research for increasing our understanding of the role of the nucleotype in evolution.
Journal Article•
TL;DR: The chromosomes of five chemical carcinogen-transformed strain 2 guinea pig fetal cell lines were identified by G and C banding techniques and were compared with the normal karyotype from secondary untreated cultures to explain their frequent participation in abnormal chromosome formation or nondisjunction.
Abstract: The chromosomes of five chemical carcinogen-transformed strain 2 guinea pig fetal cell lines were identified by G and C banding techniques and were compared with the normal karyotype from secondary untreated cultures. One line transformed by benzo( a )pyrene had a diploid constitution with no G and C band alterations. Three lines were near diploid, one was near tetraploid, and each contained abnormal chromosomes. A 3-methylcholanthrene line had an abnormal metacentric chromosome formed by centric fusion of two nonhomologous autosomes. The three N -methyl- N ′-nitrosoguanidine or diethylnitrosamine cell lines exhibited submetacentric or subtelocentric abnormal chromosomes originating from translocations between two No. 1 or a No. 1 and another autosome. The involvement of Chromosome 1 may be due to its association with nucleolar organization. The greater frequency of contact between such chromosomes, compared to other autosomes, creates an increased risk of chromatid exchange possibly explaining their frequent participation in abnormal chromosome formation or nondisjunction.
TL;DR: From data, the map position of Prt-2 has been estimated on chromosome 8, which is linked with Es-1 and Es-2 loci on chromosome8 (linkage group XVIII) and is linked very closely on the same chromosome.
Abstract: The Prt-2 locus is linked with Es-1 and Es-2 loci on chromosome 8 (linkage group XVIII). Recombination frequencies were 8.2% between Es-1 and Es-2 12.7% between Es-1 and Prt-2, and 4.5% between Es-2 and Prt-2. From these data, the map position of Prt-2 has been estimated on chromosome 8. The Prt-1 and Prt-3 loci, which are linked very closely on the same chromosome, were not determined.
TL;DR: The introduction of chromosome analysis in various blood disorders has proved the high specificity of the Philadelphia chromosome — a G22 member with deleted long arms — in the diagnosis of chronic blood disorders.
Abstract: The introduction of chromosome analysis in various blood disorders has proved the high specificity of the Philadelphia chromosome — a G22 member with deleted long arms — in the diagnosis of chronic
TL;DR: It is shown that in a23 cells the smaller chromosomes do not tend to lie nearer the metaphase plate center (as it happens in human cells), and a significant correlation between the chromosome position and the mean interchromosomal distances was not found in this type of cells.
Abstract: This study deals with a systematic chromosome position analysis of 116 anti-mitotic and hypotonic treated a23 chinese hamster cells. No chromosome or pair of chromosomes was found to be located nearer the center or the periphery of the metaphase plate than would be expected by the reference distribution. The homologous chromosomes of pair 2 lie nearer to each other but they do not form a specific angle. The same relative position was shown for the chromosome groups 1–2, 1-E1 and 2-E5 (E standing for an extra chromosome). On the other hand the chromosomes of the combinations X-7, X-8, 7–8, 8–11 and X-E2 were lying further from each other, while chromosomes 10-E1 had a greater mean angle. The non random distribution of the chromosomes 1 and 2 may be interpreted as function of their possibly more frequent participation in the organization of nucleoli. — To obtain more information about the influence of preparation techniques on the alteration of the chromosome position in metaphase plates, this study deals with some overall considerations about chromosome position. It is shown that in a23 cells the smaller chromosomes do not tend to lie nearer the metaphase plate center (as it happens in human cells). Also a significant correlation between the chromosome position with respect to the metaphase plate center and the mean interchromosomal distances was not found in this type of cells.
ARCO1
TL;DR: No quantitative correlation could be established between the degree of asynchrony in chromosome DNA replication and the extent of chromosome loss, but it appeared that telocentric chromosomes were lost more readily from those clones which started with a high hamster-to-mouse chromosome ratio.
Abstract: A number of parameters were measured in a series of 12 hybrid cell clones from Chinese hamster and mouse cells to test the hypothesis that asymmetrical chromosome loss may result from asynchrony in the replication of the two parental sets of chromosomes. All clones tended to lose telocentric (mouse) chromosomes with culture time, irrespective of the starting ratio of parental chromosomes, and in all clones, biarmed (hamster) chromosomes appeared to complete DNA replication slightly earlier than telocentrics. However, no quantitative correlation could be established between the degree of asynchrony in chromosome DNA replication and the extent of chromosome loss. It appeared that telocentric chromosomes were lost more readily from those clones which started with a high hamster-to-mouse chromosome ratio.
TL;DR: The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously.
Abstract: An infant with a typical Edwards syndrome and a modal chromosome number of 46 is reported. In all cells analyzed one chromosome G was missing and an additional chromosome similar to a pair No. 16 was present. The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously.
TL;DR: The results suggest that both chromosomes start replication simultaneously but the third chromosome appears to complete the replication earlier than the second, opening up the possibility of separate control mechanisms for the initiation and termination of DNA replication in polytene chromosomes.
Abstract: 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 complete the replication earlier than the second. These data open up the possibility of separate control mechanisms for the initiation and termination of DNA replication in polytene chromosomes.
Journal Article•
TL;DR: Monosomy 9p is reported in a boy with trigonocephaly and advanced bone age and he has been diagnosed with central giant cell granuloma.
Abstract: Monosomy 9p is reported in a boy with trigonocephaly and advanced bone age.
TL;DR: It is demonstrated in Saccharomyces cerevisiae the transposition of a gene coding for an efficient ochre (UAA) suppressor from a centromere-linked site on chromosome III to two new sites in the yeast genome.
Abstract: We have demonstrated in Saccharomyces cerevisiae the transposition of a gene coding for an efficient ochre (UAA) suppressor from a centromere-linked site on chromosome III to two new sites in the yeast genome. One site is on chromosome VI, very close to, if not allelic with, SUP11, one of eight genes coding for a tyrosine-inserting suppressor. The second site is on chromosome III, unlinked to the centromere and distal to the mating type locus. This site is very close to those mapped for the recessive lethal amber suppressors, SUP-RL1 and SUP61.
Journal Article•
Journal Article•
TL;DR: Genetic analysis of four interchanges in barley cultivar K 12 was carried out to locate the breakpoints in chromosome arms, utilizing F2 data, and average ovule sterility in inter-change heterozygotes was found to be 28.7%.
Abstract: Genetic analysis of four interchanges in barley cultivar K 12 was carried out to locate the breakpoints in chromosome arms, utilizing F2 data. T 2-6 was located in the long arm of chromosome 2 and short arm of chromosome 6 while T 6-7 was located in the long arm of the two chromosomes. T 3-7 was placed in the short arm of the two chromosomes. Location of breakpoint in T 2-4 was in the short arm of chromosome 2. Average ovule sterility in inter-change heterozygotes was found to be 28.7%.
TL;DR: In analyzing human diploid cell strain Wi-38, by the use of C-bands, it is found that hetercchromatin blocks are equal on chromosome pairs 1 and 16, but are unequal on chromosome pair 9.