Showing papers on "Chromosome 22 published in 1979"
TL;DR: Two fragments cloned from purified human satellite III DNA do not cross-react with each other and are shown to originate on chromosome 1 and from the Y chromosome.
Abstract: Two fragments cloned from purified human satellite III DNA do not cross-react with each other. One fragment, for which a partial sequence is reported, hybridises to satellite II as well as III and is shown to originate on chromosome 1. The other cloned fragment originates from the Y chromosome. This fragment has undergone considerable changes in size when cloned in lambda gt WES lambda B. Human satellite III is shown to consist of a number of non-cross-reacting sequences which nevertheless are related by the presence of closely spaced Hin F1 sites.
475 citations
TL;DR: Experimental evidence indicates that the repeating ribosomal DNA (rDNA) genes of the yeast Saccharomyces cerevisiae are located on chromosome XII, and establishes that in mitosis most of the rDNA genes in yeast are not extrachromosomal.
Abstract: Two lines of experimental evidence indicate that the repeating ribosomal DNA (rDNA) genes of the yeast Saccharomyces cerevisiae are located on chromosome XII. First, the rDNA genes are linked mitotically to genes that have been previously mapped to chromosome XII. Second, yeast strains that have two copies of the chromosome containing the rDNA genes in every strain examined also have two copies of chromosome XII; this is not true for the other yeast chromosomes. These data also establish that in mitosis most of the rDNA genes in yeast are not extrachromosomal.
222 citations
TL;DR: Cloned DNA probes were used in combination with a panel of five hybrid cell clones containing a series of different terminal deletions in human chromosome 11 to map precisely the human hemoglobin beta and delta chain structural genes contained on this chromosome.
Abstract: Cloned DNA probes were used in combination with a panel of five hybrid cell clones containing a series of different terminal deletions in human chromosome 11 to map precisely the human hemoglobin beta and delta chain structural genes contained on this chromosome. The region of deletion in each clone of the panel has been defined by biochemical, immunologic, and cytogenetic markers. DNA from clones containing successively larger terminal deletions was tested with appropriate DNA probes to determine the point on the chromosome at which DNA for these two closely linked hemoglobin genes is deleted. These genes, and by inference the closely linked G gamma and A gamma globin genes as well, have been assigned to the intraband region 11p1205 leads to 11p1208 on the short arm of chromosome 11, an interval containing approximately 4500 kilobases of DNA. The approach appears to have potential for even greater resolution and reasonably wide applicability for gene mapping.
141 citations
TL;DR: Genetic and physical characterization of rearrangements of chromosome III which result in changes of cell type in S. cerevisiae are described and it is suggested this deletion removes MATalpha and activates cryptic MATa information stored in HMalpha as proposed in the cassette model of mating type interconversion.
137 citations
01 Jan 1979
TL;DR: The Origin of Man, the Most Intelligent Ape, and The Human Paradox: Intelligence, Ape and Man, a Review of the Theory of Evolution, Genes, and Chromosomes.
Abstract: Section I. The Origin of Man.- 1. Man, the Most Intelligent Ape.- The Human Paradox.- Intelligence, Ape and Man.- References.- 2. The Fossil Record and the Emergence of Modern Man.- Africa Versus Asia Darwin Versus Haeckel.- The Fossil Record in Africa.- Yet Man Could Have Emerged in Asia.- Ramapithecus, Dryopithecus and the Great Apes.- From Homo erectus to Homo sapiens.- References.- 3. Man and His Classification.- The Conflict of Organic and Molecular Evolution.- References.- 4. The Theory of Evolution, Genes, and Chromosomes.- Natural Selection and Mendelian Genetics.- Chromosomes, the Vehicles of Inheritance.- References.- Section II. Cytotaxonomy and the Evolution of Man and the Great Apes.- 5. The Chromosomes of Man and the Great Apes. The Inference of Interspecific Homology.- Chromosome Number in the Hominidae.- Comparative Studies with Chromosome Banding Techniques.- 1. G-and R-Banding.- 2. Q-Banding.- 3. C-Banding.- 4. G-11 Staining.- 5. Methylated DNA Sequences.- 6. T-Banding.- 7. Ammoniacal Silver (Ag-AS) Staining.- The Inference of Chromosome Homology Through Different Degrees of Similarity.- 1. Chromosomes with Identical Morphology and G- (or R-) Banding Pattern in All Species.- 2. Chromosomes with Very Similar Morphology in All Species.- 3. Homologous Chromosomes Between Species Which Can Be Derived from Each Other by Chromosome Rearrangement of G- (or R-) Band Regions.- 4. Homologous Chromosomes With a Similar Morphology but With G- Banding Pattern Which Neither Coincides With Nor Can be Derived by Chromosome Rearrangement.- 5. Chromosomes Having no Similar Counterpart in Any Other Species.- The Y Chromosome.- References.- 6. Chromosome Heteromorphisms in Man and the Great Apes as a Source of Chromosome Variation Within Species.- Chromosome Heteromorphisms in Man.- Chromosome Heteromorphisms in the Great Apes.- 1. Chromosome Heteromorphisms in Pan troglodytes.- 2. Chromosome Heteromorphisms in Pan paniscus.- 3. Chromosome Heteromorphisms in Gorilla gorilla.- 4. Chromosome Heteromorphisms in Pongo pygmaeus.- Phylogenetic Implications of Chromosome Variation in the Orangutan.- References.- 7. Chromosome Rearrangement and the Phylogeny of the Hominidae.- Inversions and Telomeric Fusions.- Implications of Chromosome Rearrangement: a Comparison with Other Species.- 1. Inversions.- 2. Translocations and Centric Fission.- 3. Telomeric Fusion.- The Reconstruction of the Ancestral Karyotype of the Hominidae and the Relationship Between Man and the Great Apes.- References.- 8. Chromosome Variation Versus Chromosome Fixation.- Allopatric and Stasipatric Models of Speciation.- References.- Section III. Comparative Gene Mapping And Molecular Cytogenetics. A New Approach to Cytotaxonomy.- 9. Composition of the Human Genome.- Repetitive and Non-Repetitive DNA Sequences.- Palindromes and Tandem Repeats.- Satellite DNA and Sequence Heterogeneity.- References.- 10. Evolution of Non-Repetitive DNA Sequences in Man and the Great Apes.- Nucleotide Substitutions and Phyletic Divergence.- Man and the Great Apes: Phylogenetic Implications.- Is Man an Asian Ape?.- References.- 11. Evolution of Structural Gene Sequences.- Missense Mutations and Amino Acid Substitutions.- Molecular Evolutionary Clocks and the Human-Ape Divergence.- The Maximum Parsimony Approach and the Decelerated Rates of Molecular Evolution in the Higher Primates and Man.- Whence Come Chromosomes?.- References.- 12. Comparative Gene Mapping in Man and Other Primates.- The Evolution of Chromosomes as Syntenic Groups.- The Conservation of the Syntenic Groups Among the Hominidae and Cercopithecoidea.- Comparative Gene Mapping Between Hominidae-Cercopithe- coidea and the Possible Origin of Chromosome 1 in Man.- Are Chromosomes Frozen Accidents?.- Gene Duplication, Polyploidy, and Evolutionary Frozen Chromosomes.- References.- 13. Evolution of Repetitive DNA Sequences in Man and Other Primates.- Repetitive DNA in the Primates.- Repetitive DNA in Man.- Satellite DNAs in Man and Other Organisms. Possible Explanations of Their Evolutionary Conservation.- References.- 14. The Chromosome Distribution of Homologous Sequences to the Four Human Satellite DNAs in the Hominidae.- The Distribution of Satellite I, II, III and IV in the Human Chromosome Complement.- The Distribution of Homologous Sequences to the Four Human Satellite I, II, III, and IV DNA in the Chromosome Complement of the Great Apes.- Interspecific Chromosome Homologies in the Hominidae in Relation to Hybridisation. Independent Amplification of Highly Repetitive DNAs After Speciation.- References.- 15. DNA Composition of Constitutive Heterochromatin in the Chromosome Complement of Man and the Great Apes.- Constitutive Heterochromatin as Demonstrated by C-Banding.- G-11 Regions and Satellite III-Rich Regions.- References.- 16. The Chromosomal Distribution of Ribosomal Genes in Man and the Great Apes.- rDNA Genes in Man.- 18S and 28S Cistrons in the Great Apes and Other Primates.- 5S rDNA Cistrons in Man and the Great Apes.- References.- 17. Late DNA Replicating Patterns in the Chromosomes of Man and the Great Apes.- DNA Replication at the Chromosome Level.- DNA Replication Sites in Relation to Chromosome Banding.- The X Chromosome.- Euchromatin, Heterochromatin and DNA Replication.- References.- 18: Evolution of Genome Size in Man and the Great Apes.- The DNA Content of Man and Other Organisms.- Why Has DNA Content Changed?.- References.
80 citations
TL;DR: Results substantiate the localization of beta- and delta-globin genes to human chromosome 11 and exclude the region 11q23-qter as the site.
Abstract: DNA from a clone of a mouse-human hybrid that retained a human chromosome consisting of the major part of chromosome 11 and region q25-26-qter of the X chromosome was digested with various restriction endonucleases, subjected to electrophoresis in agarose gels, and transferred to nitrocellulose filters. The restriction digest pattern of the clone, when hybridized with a 32P-labeled plasmid fragment containing human beta-globin gene sequences, was a composite of the normal human and mouse (A9) patterns. When back-selected in 6-thioguanine to eliminate the 11 translocation chromosome, the hybrid cells showed only the A9 restriction pattern. These results substantiate the localization of beta- and delta-globin genes to human chromosome 11 and exclude the region 11q23-qter as the site.
79 citations
TL;DR: The total number of families of Y-specific sequences, calculated on the basis of reiteration frequency and total abundance in a male genome, greatly exceeds the number of Y -specific sequences present in a single 3.4-kb molecule, so it necessarily follows that the population of these 3.
Abstract: Fragments of 3.4 kilobases (kb) are released from DNA of human males, but not DNA of human females, by cleavage with restriction endonucleases HaeIII, EcoRI, or EcoRII. Most, if not all, reiterated DNA which is specific for the Y chromosome (it-Y DNA) is present within these male-specific 3.4-kb molecules. Although such 3.4-kb molecules are themselves localized to the Y chromosome, this is not true for all sequences within them. At least two distinguishable types of reiterated sequences are found within each 3.4-kb molecule. One type consists of at least two families which are highly reiterated and are not confined to the Y chromosome. The other type is composed of an estimated minimum of 39 families, each moderately reiterated and localized to the Y chromosome. Y-specific and non-Y-specific sequences are interspersed with one another in the same 3.4-kb molecule. In the average 3.4-kb molecule, three 800 nucleotide lengths of Y-specific sequences alternate with four 250 nucleotide lengths of non-Y-specific sequences. Since the total number of families of Y-specific sequences, calculated on the basis of reiteration frequency and total abundance in a male genome, greatly exceeds the number of Y -specific sequences present in a single 3.4-kb molecule, it necessarily follows that the population of these 3.4-kb molecules is heterogeneous.
57 citations
TL;DR: Experiments are described in which human cells carrying balanced reciprocal translocations involving four different regions of chromosome 9 were fused with a Chinese hamster cell line and the resulting hybrids used to obtain subchromosomal assignments of the loci ASS, AK3, and ACONS.
Abstract: Experiments are described in which human cells carrying balanced reciprocal translocations involving four different regions of chromosome 9 were fused with a Chinese hamster cell line and the resulting hybrids used to obtain subchromosomal assignments of the loci ASS, AK3, and ACONS. ASS was localized on the distal portion of the long arm of chromosome 9, in the region 9q34 leads to 9qter, and AK3 and ACONS on the short arm, in the region 9pter leads to 9p13.
52 citations
Journal Article•
TL;DR: The regional localization of AK1 locus permits the localization of the AK1-Np-ABO linkage group and the assignment of the loci for the enzymes galactose-1-phosphate uridyltransferase, soluble aconitase, and adenylate kinase-3 (AK3) to the short arm of chromosome 9.
Abstract: Somatic cell hybrids were derived from the fusion of (1) Chinese hamster cells deficient in hypoxanthine guanine phosphoribosyltransferase (HPRT) and human cells carrying an X/9 translocation and (2) Chinese hamster cells deficient in thymidine kinase (TK) and human cells carrying a 17/9 translocation. Several independent primary hybrid clones from these two series of cell hybrids were analyzed cytogenitically for human chromosome content and electrophoretically for the expression of human markers known to be on human chromosome 9. The results allow the assignment of the loci for the enzymes galactose-1-phosphate uridyltransferase (GALT), soluble aconitase (ACONs), and adenylate kinase-3 (AK3) to the short arm of chromosome 9 (p11 to pter) and the locus for the enzyme adenylate kinase-1 (AK1) to the distal end of the long arm of human chromosome 9 (hand q34). Earlier family studies have shown that the locus for AK1 is closely linked to the ABO blood group locus and to the locus of the nail-patella (Np) syndrome. Thus the regional localization of AK1 locus permits the localization of the AK1-Np-ABO linkage group.
51 citations
TL;DR: Characterization of the chromosome 21-specific RNA sequences quantitated in these experiments could help to elucidate the mechanisms by which abnormal karyotypes result in abnormal phenotypes.
Abstract: Chromosome imbalance (aneusomy) is the leading known cause of both spontaneous abortion and mental retardation in human beings. The primary abnormality is thought to result from quantitative changes of transcription products from the unbalanced genetic material. To document this point, I compared chromosome 21-specific transcription in skin fibroblasts from subjects with monosomy 21, disomy 21 (normal), and trisomy 21 (Down syndrome). Polyadenylylated RNA [poly(A)-RNA], which is enriched in messenger and messenger-precursor RNA sequences, was isolated from the above fibroblast lines. Radioactive DNA (cDNA) complementary to these RNAs was synthesized with reverse transcriptase (RNA-dependent DNA polymerase). These cDNAs were hybridized with (i) DNA from a cell line with a mouse genome plus human chromosome 21 and (ii) mouse DNA. Subtraction of the amount of hybridization in experiment ii from that in experiment i yielded a measure of human chromosome 21-specific RNA sequences. The results were consistent with gene dosage at the transcriptional level; for monosomy 21-derived cDNA, 0.6% (of the total cDNA) hybridized specifically to human chromosome 21; for disomy 21-derived cDNA, 2% hybridized; and for trisomy 21-derived cDNA, 3% hybridized. Thus, for DNA sequences on chromosome 21 in human skin fibroblasts, transcription depends on DNA dosage. Characterization of the chromosome 21-specific RNA sequences quantitated in these experiments could help to elucidate the mechanisms by which abnormal karyotypes result in abnormal phenotypes.
50 citations
TL;DR: Observations substantiate the prior tentative assignments of an ARS-A locus to chromosome 22 and a B-GAL locu to chromosome 3 and the implications of the chromosome assignments of loci for 12 human lysosomal enzymes for the cellular assembly of these organelles are discussed.
Abstract: The segregation of human lysosomal arylsulfatase A (ARS-A) has been evaluated in 50 primary hybrid clones derived from four separate fusions involving WBCs from two unrelated individuals and three hamster cell lines. ARS-A was expressed in the hybrids as a dimeric molecule of very similar or identical subunits. The expression of this enzyme was concordant with that of mitochondrial aconitase (ACON-M), an isozyme assigned to chromosome 22, in all 50 clones and with chromosome 22 segregation in all but one of the 29 karyotyped hybrids. No other human chromosome cosegregated with 22 in these clones, suggesting that this enzyme is specified in hybrid cells by a locus (or loci) on a single chromosome. β-Galactosidase (B-GAL) expression was analyzed with two different electrophoresis systems and with a number of cell extract preparation methods in 39 of the primary hybrid clones. The B-GAL isozyme expressed in these hybrid cells was concordant with the expression of glutathione peroxidase-1 (GPX-1), an isozyme assigned to chromosome 3, in all 39 clones and with the segregation of this chromosome in 97% of the 29 karyotyped hybrids. These observations substantiate the prior tentative assignments of an ARS-A locus to chromosome 22 and a B-GAL locus to chromosome 3 (Bruns et al., 1978a, b). The implications of the chromosome assignments of loci for 12 human lysosomal enzymes for the cellular assembly of these organelles are discussed.
TL;DR: Human X chromosome DNA was partially purified from a mouse-human hybrid cell line containing a single human chromosome, the X, suggesting that the remainder may have homology with mouse DNA.
Abstract: Human X chromosome DNA was partially purified from a mouse-human hybrid cell line containing a single human chromosome, the X. Enrichment of such DNA was accomplished by two sequential reassociations of radiolabeled hybrid cell DNA with large excesses of mouse DNA. Unreassociated hybrid cell DNA was used as a probe for human X chromosome sequences. The human-specific fraction of probe DNA CONTAINED THREE COMPONENTS. Two of these reassociated to human DNAs at rates proportional to the number of X chromosomes present. These two components were thus localized to the X chromosome. One of these X-specific components, representing about 80% of human-specific probe DNA, consisted of single copy or very low order reiterated DNA. The second X-specific component, representing about 10% of human-specific probe DNA, was about 20-30 times more reiterated. The remaining 10% of human-specific probe DNA, although derived from the X chromosome, reassociated to human DNAs at a rate independent of the number of X chromosomes present. This component was thus homologous to autosomal as well as X chromosome DNA. The probe DNA accounts for approximately half of the human X chromosome, suggesting that the remainder may have homology with mouse DNA.
TL;DR: Although the multiple sulfatase deficiency disorder suggests a shared relationship between ARs(A) and ARS(B), independent segregation of these enzymes in cell hybrids did not support a common polypeptide subunit or structural gene assignment.
Abstract: Genetics of human lysosomal arylsulfatases A and B (aryl-sulfate sulfohydrolase, EC 3.1.6.1), associated with childhood disease, has been studied with human-rodent somatic cell hybrids. Deficiency of arylsulfatase A (ARSA) in humans results in a progressive neurodegenerative disease, metachromatic leukodystrophy. Deficiency of arylsulfatase B (ARSB) is associated with skeletal and growth malformations, termed the Maroteaux-Lamy syndrome. Simultaneous deficiency of both enzymes is associated with the multiple sulfatase deficiency disease, suggesting a common relationship for ARSA and ARSB. The genetic and structural relationships of human ARSA and ARSB have been determined by the use of human-Chinese hamster somatic cell hybrids. Independent enzyme segregation in cell hybrids demonstrated different chromosome assignments for the structural genes, ARSA and ARSB, coding for the two lysosomal enzymes. ARSA activity showed concordant segregation with mitochondrial aconitase encoded by a gene assigned to chromosome 22. ARSB segregated with β-hexosaminidase B encoded by a gene assigned to chromosome 5. These assignments were confirmed by chromosome analyses. The subunit structures of ARSA and ARSB were determined by their electrophoretic patterns in cell hybrids; a dimeric structure was demonstrated for ARSA and a monomeric structure for ARSB. Although the multiple sulfatase deficiency disorder suggests a shared relationship between ARSA and ARSB, independent segregation of these enzymes in cell hybrids did not support a common polypeptide subunit or structural gene assignment. The evidence demonstrates the assignment of ARSA to chromosome 22 and ARSB to chromosome 5. A third gene that affects ARSA and ARSB activity is suggested by the multiple sulfatase deficiency disorder.
TL;DR: A behaviorally and clinically abnormal female orangutan was analyzed cytologically using general banding techniques and by an alkaline silver method for staining nucleolus organizer regions.
Abstract: A behaviorally and clinically abnormal female orangutan was analyzed cytologically using general banding techniques and by an alkaline silver method for staining nucleolus organizer regions. The karyotype had 49 chromosomes, including an extra chromosome 22 (49, XX, + 22). No variant chromosome types or heterozygous structural rearrangements were found. Nine of the 14 large acrocentric chromosomes, Nos. 11–17, and three of the five presumptive human G-group equivalents, i.e., two of three chromosomes 22, and one chromosome from pair 23, exhibited positive silver staining of the nucleolus organizer region (NOR).
TL;DR: Observations are consistent with the view that the instability of the Uc lines is caused by a transposable element capable of site-specific chromosome breaks and perpetual generation of mutations.
Abstract: During a study of delayed mutations, an unstable X chromosome (Uc) was detected. Spontaneous X-linked recessive lethal mutations were detected in 34 of 993 sperm sampled from 50 males carrying this chromosome. All but three of the 34 lethals originated as clusters in three of the 50 males Cytogenetic and complementation analyses revealed 14 intrachromosomal rearrangements: ten inversions, two reverse repeats, one deficiency and one transposition. Eight of the 14 rearrangements have one break in the 6F1–2 doublet and two rearrangements have a break in 6F1–5 of the X chromosome. The remaining four rearrangements have in addition to the aberrations a lethal point mutation between 6F1 and 6F5. Though each of the lethal lines was established from a single lethal-bearing female, chromosome polymorphism is evident in 17 of the 18 lines having rearrangements, with certain aberrations recurring in several lines. The lethal mutations revert frequently to the nonlethal state, and cytological evidence indicates that more than one mutational event may occur at the unstable locus of the chromosome during one generation. Two lethal lines had more than one type of chromosome rearrangement sharing a common breakpoint. These observations are consistent with the view that the instability in the Uc lines is caused by a transposable element capable of site-specific chromosome breaks and perpetual generation of mutations. The mutagenic and genetic properties of transposable elements can be related to the two-mutation theory of Knudson (1971) for cancer initiation.
TL;DR: The differential behaviour of autosomal and sex chromosome associated satellite DNAs is discussed in the light of gene regulation.
Abstract: Sex chromosome associated satellite DNAs isolated from the snakes Elaphe radiata (sat III) (Singh et al., 1976) and Bungarus fasciatus (Elapidae) (minor satellite) are evolutionarily conserved throughout the suborder Ophidia. An autosome limited satellite DNA (B. fasciatus major satellite) is not similarly conserved. Both types of satellites have been studied by in situ hybridisation in various somatic tissues and germ cells where it has been observed that the W sex chromosome remains condensed in interphase nuclei. In growing oocytes however, the W chromosome satellite rich heterochromatin decondenses completely whilst the autosomal satellite rich regions remain condensed. Later, the cycle is reversed and the W chromosome condenses whilst the autosomal satellite regions decondense. In a primitive snake (Eryx johni johni) where the sex chromosomes are not differentiated and where there is no satellite DNA specific to them, these phenomena are absent. — The differential behaviour of autosomal and sex chromosome associated satellite DNAs is discussed in the light of gene regulation.
TL;DR: A new chromosome banding technique, distamycin A plus DAPI, has been used to reexamine cases of presumed Y/autosome translocations, and shows that the Yq nature of additional material on 15p supports the previous diagnosis of a presumptive 15/Y translocation.
Abstract: A new chromosome banding technique, distamycin A plus DAPI, has been used to reexamine cases of presumed Y/autosome translocations. In contrast with the results obtained with quinacrine fluorescence (Q-banding), the satellites of acrocentric chromosomes do not fluoresce brightly with this new (DA-DAPI) method, making it more specific for the long arm of the Y chromosome. Previous cases with intensely Q-fluorescent and abnormally long short arms on a chromosome 22 were considered as presumptive 22/Y translocations: The new technique clearly shows that, in these cases, the additional material on 22p is not derived from Yq. In contrast, in other cases the Yq nature of additional material on 15p, in conjunction with the presence of an extra Y-body in interphase nuclei and the presence of a male-specific DNA, supports the previous diagnosis of a presumptive 15/Y translocation.
TL;DR: It was concluded that the gene(s) that tend to duplicate in parallel with the neoplastic transformation of the prothymocyte to an overt leukemie cell have a greater chance of duplicating and/or may have a stronger promoting effect on leukemogenesis if located on the CBA‐derived, structurally rearranged T(14:15)6 than the corresponding genes located in the C57BL‐derived normal chromosome 15.
Abstract: Trisomy of chromosome 15 is a highly regular feature of murine T-cell leukemogenesis. We have studied the chromosomal constitution of 7,12-dimethylbenza(a)anthracene (DMBA)-induced T-cell leukemias in C57BL X CBAT6T6 F1 mice. The CBAT6T6-derived chromosome T(14:15)6 was regularly duplicated whereas the C57BL-derived normal chromosome 15 was only present in one copy. It was concluded that the gene(s) that tend to duplicate in parallel with the neoplastic transformation of the prothymocyte to an overt leukemic cell have a greater chance of duplicating and/or may have a stronger promoting effect on leukemogenesis if stronger promoting effect on leukemogenesis if located on the CBA-derived, structurally rearranged T(14:15)6 than the corresponding genes located on the C57BL-derived normal chromosome 15.
TL;DR: A family with an insertional type of chromosome rearrangement involving chromosomes 7 and 13 is reported, with three subjects who were monosomic for the involved segment of chromosome 7.
Abstract: A family with an insertional type of chromosome rearrangement involving chromosomes 7 and 13 is reported. An interstitial deletion of a segment of chromosome 7 (7q32 leads to 34) had been inserted into the long arm of chromosome 13 at breakpoint q32. Segregation of this chromosome rearrangement gave rise to three subjects who were monosomic for the involved segment of chromosome 7. The karyotypes were: 46,XX, or XY,der(7)ins(13;7) (q32;q32q34). All three subjects were mentally retarded and had minor dysmorphic features. The Kidd, Colton, and Kell blood group systems were investigated, but were not informative.
TL;DR: Using a Giemsa C-banding procedure three chromosome pairs have been identified in meiosis of the F1 of a cross between two rye inbred lines and two of these chromosome pairs were heterozygous for a prominent telomeric heterochromatic band.
Abstract: Using a Giemsa C-banding procedure three chromosome pairs (3, 6 and 7) have been identified in meiosis of the F1 of a cross between two rye inbred lines. Two of these chromosome pairs (3 and 7) were heterozygous for a prominent telomeric heterochromatic band. The comparison between the frequencies of the different meiotic configurations at metaphase I, anaphase I and metaphase II presented by these two chromosome pairs has allowed the estimation of the chiasma frequency and the genetic length of the chromosome arms 3 short and 7 long.
TL;DR: The his4C transpositions are unstable and give rise to C- segregants at a high frequency, as a result of either precise excision of the his 4C gene (restoring function of the gene into which insertion had occurred) or chromosome loss.
Abstract: Unstable transpositions in yeast have been selected in which the his4C gene from chromosome III is inserted into chromosome XII. This event is associated with the generation of a recessive lethal mutation, resulting from the integration of his4C into an essential gene. Strains with these transpositions are viable as diploids or aneuploids for chromosome XII. The event that generates the transpositions does not lead reciprocally to a deletion on chromosome III, implying that synthesis of a new copy of his4C and subsequent transposition may have occurred. The his4C transpositions are unstable and give rise to C- segregants at a high frequency, as a result of either precise excision of the his4C gene (restoring function of the gene into which insertion had occurred) or chromosome loss.
TL;DR: A class of recurring, noncomplementing, recessive, temperaturesensitive mutation of BHK-21 cells has been assigned to the X chromosome by complementation, karyotypic, and enzyme analyses.
Abstract: A class of recurring, noncomplementing, recessive, temperaturesensitive mutation of BHK-21 cells has been assigned to the X chromosome. X-linkage was determined by complementation, karyotypic, and enzymatic analyses.
TL;DR: The authors' results confirm the assignment of ARSA to chromosome 22 and confirm the presence of marker enzymes in human/hamster hybrid cell cultures.
Abstract: Human/hamster hybrid cell cultures were examined for the presence of ARSA and other marker enzymes. Many of these hybrids were also analyzed for human chromosomes. Our results confirm the assignment of ARSA to chromosome 22.
TL;DR: This observation provides the first instance where two selectable markers (heat resistance and 8-azaguanine sensitivity) are found on a single human chromosome and suggests that these markers may prove to be a valuable push-pull selective system of use in determining the linear arrangement of genes on human chromosomes by somatic cell genetics.
Abstract: GM 126 human diploid fibroblasts were fused with a heat-sensitive mouse cell mutant defective in DNA synthesis, and primary hybrids were selected at permissive and nonpermissive temperatures in HAT medium. Primary hybrids, primary hybrid clones back-selected in 8-azaguanine at the permissive temperature, and subclones of heat-resistant primary hybrids isolated under nonselective conditions or after 8-azaguanine treatment were tested for heat sensitivity, the expression of 26 human enzymes assigned to 19 different human chromosomes, and the presence of human chromosomes. Only the human X chromosome and X-linked marker enzymes exhibited a clear pattern of concordant segregation with the heat-resistant phenotype. On the basis of these observations, we have defined the human genetic locus that corrects the heat-sensitive lesion in tsC1AGOH as hrC1AGOH and have assigned this locus to the X chromosome. This observation provides the first instance where two selectable markers (heat resistance and 8-azaguanine sensitivity) are found on a single human chromosome and suggests that these markers may prove to be a valuable push-pull selective system of use in determining the linear arrangement of genes on human chromosomes by somatic cell genetics.
TL;DR: Results of neuraminidase treatment of the cell lysates and immunological studies showed that in man two structural β-galactosidase loci are present and can be assigned to chromosomes 3 and 22.
Abstract: Hybrid cell lines isolated after fusions between Chinese hamster E36 cells and normal human white blood cells were analyzed for human β-galactosidase isoenzymes and for human chromosomes, especially 3, 12, and 22, the candidates for bearing a β-galactosidase locus. Results of neuraminidase treatment of the cell lysates and immunological studies showed that in man two structural β-galactosidase loci are present and can be assigned to chromosomes 3 and 22. No correlation was found between the expression of human β-galactosidase and the presence of human chromosome 12.
TL;DR: The karyotype of a spontaneous mouse B-cell leukemia passaged intravenously several times in succession into syngeneic recipients was determined and peripheral lymphocytes from a control animal and from animals in passage 1 and 7 were stimulated by the mitogen lipopoly-saccharide, and studied by Giemsa banding methods.
TL;DR: Two cases of chromosomal translocations involving the long arm of chromosome 1 were investigated for 5S ribosomal gene localisation using in situ hybridisation, confirming a previous assignment based on adenovirus-induced uncoiling and on a partial trisomy.
Abstract: Two cases of chromosomal translocations involving the long arm of chromosome 1 were investigated for 5S ribosomal gene localisation using in situ hybridisation. In the first family, there was an interstitial translocation of 1q25-32 to chromosome 5; the 5S genes remained on chromosome 1. In the second family, there was a translocation of 1q42-44 to chromosome 21q12; the 5S gene locus in this case was translocated. This shows that the 5S ribosomal genes are at position 1q42-44, confirming a previous assignment based on adenovirus-induced uncoiling and on a partial trisomy (Steffensen et al., 1977).
TL;DR: Analysis of the hybrid clones for the expression of the enzyme and the presence of the translocation chromosome 1 has permitted the assignment of the gene for human UDPGal 4-epimerase to the pter yields p32 region of chromosome 1.
Abstract: Somatic cell hybrids between mouse and human cells containing two different reciprocal translocations involving human chromosome 1, 46, X, t(l;X)(ql2;q26) and 47, XX, + 21, t(l;17)(p32;pl3), were studied for the expression of human uridine diphosphate galactose 4-epimerase (UDPGal 4-epimerase, EC 5132) by starch-gel electrophoresis Analysis of the hybrid clones for the expression of the enzyme and the presence of the translocation chromosome 1 has permitted the assignment of the gene for human UDPGal 4-epimerase to the pter→p32 region of chromosome 1
TL;DR: It was found that chromosome 17 terminated replication much earlier than chromosome 7, therefore, the relationship between the replication times of these chromosomes normally observed in human cells was maintained in the hybrids in the absence of all other human chromosomes.
Abstract: The time of termination of DNA replication of human chromosomes in human-mouse hybrids retaining only one human chromosome was analyzed. Hybrids between SV40-transformed human skin fibroblasts and mouse peritoneal macrophages were used for these studies. Data obtained from hybrids containing only human chromosome 7 or 17 were compared with data from related hybrids containing additional human chromosomes. When either human chromosome 7 or 17 was present alone, it terminated replication at the same stage of the S phase as in hybrids in which other human chromosomes were present (relative to the time of termination of replication of the mouse chromosomes). In comparing the hybrids containing single human chromosomes, it was found that chromosome 17 terminated replication much earlier than chromosome 7. Therefore, the relationship between the replication times of these chromosomes normally observed in human cells was maintained in the hybrids in the absence of all other human chromosomes. The results also indicate that the presence of SV40 gene sequences in chromosomes 7 and 17 did not alter the relative times of termination of replication of those chromosomes.