bluuebunny/crossref_metadata_2025 huggingface dataset:
A human 9;20 reciprocal translocation associated with male infertility analyzed at prophase and metaphase I of meiosis
Authors: Chandley A.C. , Speed R.M. , McBeath S. , Hargreave T.B.
Published: May 2008

Details are given of a meiotic prophase analysis, carried out by spreading, of a human 9;20 reciprocal translocation ascertained in a subfertile, oligospermic male. Air-dried meiotic preparations revealed the presence of translocation quadrivalents at metaphase I. Germ-cell degeneration was evident from the early prophase of meiosis onward. Associations between the translocation quadrivalent and XY bivalent at pachytene were seen in only 20% of the cells and seemed not to be the prime cause of germ-cell failure. Pairing disruption around the breakpoints of the translocation at pachytene and/or pairing failure in one arm of the pachytene cross was observed in a total of 87% of all cells analyzed. This could have contributed significantly to germ-cell atresia.
Reduced oocyte numbers in tertiary trisomic mice with male sterility
Authors: Setterfield L.A. , Mittwoch U.
Published: May 2008

Oocyte counts carried out in 3- to 5-day-old tertiary trisomic Ts(512)31H mice revealed a mean reduction of 71% in the number of oocytes as compared with that of normal littermates. The pool of small oocytes was reduced by 75%, and the number of growing oocytes by 8%. The sperm count of the trisomic males was less than 1% of normal, with most spermatozoa being abnormal (Beechey et al., 1980). These results indicate that the presence of the extra 512 chromosome, which causes male sterility, also has a marked effect on oogenesis. Possible reasons for the difference in severity of the gametogenic impairment in males and females are discussed.
The gene for clotting factor 10 is mapped to 13q32→qter
Authors: Royle N.J. , Fung M.R. , MacGillivray R.T.A. , Hamerton J.L.
Published: May 2008

The structural gene for the human clotting factor 10 (F10) has been mapped to chromosome 13 with a cDNA probe hybridized to DNAs from a panel of human × hamster hybrids. In situ hybridization was used to assign F10 to region 13q32→qter of chromosomes from normal human lymphocytes.
Chromosome elimination in the Japanese hagfish, Eptatretus burgeri (Agnatha, Cyclostomata)
Authors: Kohno S. , Nakai Y. , Satoh S. , Yoshida M. , Kobayashi H.
Published: May 2008

The modal number of chromosomes in Eptatretus burgeri was 36 in 297 (81.8%) of 363 somatic cells, 52 in 13 (30.2%) of 43 spermatogonia, and 25 (46.8%) or 26 (40.3%) in 162 of 186 first spermatocytes. The relative amount of DNA in a somatic cell to that in a spermatogonium averaged 79.2%. C-band-positive chromatin was observed along almost the entire length of the associated dumbbell-shaped bivalents and part of two other bivalents in the metaphases of first spermatocytes, but was rarely observed in somatic cells. These results indicate that, in E. burgeri, chromosome elimination takes place during the early stages of cleavage, except for the ancestral germ-line cells.
Phenotypic heterogeneity in three cases of lymphoid malignancy with chromosomal translocations in 14q11
Authors: Dubé I.D. , Greenberg M.L.
Published: May 2008

Lymphoid malignancies bearing translocations involving the region 14q 11 are thought to have a T-cell phenotype because their pathogenesis is postulated to involve the aberrant juxtaposition of DNA sequences active in T-cell differentiation (T-cell antigen receptor genes) and proto-oncogenes. We present here three lymphoid malignancies with translocations involving 14q11. Although one had a T-cell phenotype, the other two had B-cell lineage phenotypes. Our findings confirm that not all lymphoid malignancies with translocations involving 14q 11 represent T-cell clonal expansions.
Multistranded organization of the lateral elements of the synaptonemal complex in the rat and mouse
Authors: del Mazo J. , Gil-Alberdi L.G.
Published: May 2008

Using electron microscopy, we have analyzed the structure of the lateral elements (LEs) of the synaptonemal complex (SC) in rat and mouse spermatocytes under different spreading conditions. Our observations indicate that in nearly 50% of the cells it is possible to detect more than one structural component of the LEs in the XY pair. When the same spreading conditions are used, the structure of the LEs is not the same in the autosomes and the XY pair. Moreover, the correlation between different spreading conditions and the detection of more than one sublateral element (subLE) was different in pachytene and diplotene spreads; it also varied depending on the species and meiotic stage. Our study supports the notion that the LEs of the SC are multistranded.
The XYY condition in a wild mammal: an XY/XYY mosaic common shrew (Sorex araneus)
Authors: Searle J.B. , Wilkinson P.J.
Published: May 2008

XY/XYY sex-chromosome mosaicism was demonstrated in both bone marrow and germ cells of a wild adult common shrew. Secondary sexual characteristics were those of a normal male, but the testes were small, and the sperm count was only about 3% of normal. Most of the seminiferous tubule cross-sections examined revealed serious spermatogenic impairment and a reduced diameter. A range of sex-chromosome pairing configurations was observed in XYY primary spermatocytes, including configurations involving the X and both Y chromosomes in a linear or radial array. The presence of metaphase II (MII) spreads with an XY sex-chromosome complement indicated that XYY primary spermatocytes could contribute products to MII. Following Burgoyne (1979) and Burgoyne and Biddle (1980), a number of models of spermatocyte loss were tested. The data indicated that there was an association between the sex-chromosome complement of primary spermatocytes and their contribution to MII The best fit to the observed MII frequency data was provided by a model which assumed that all XYY primary spermatocytes with a univalent Y chromosome and a high proportion of XYY primary spermatocytes with an unpaired X chromosome failed to contribute products to MII.
DNA polymorphisms indicate loss of heterozygosity for chromosome 11 of D98AH2 cells
Authors: Kaelbling M. , Roginski R.S. , Klinger H.P.
Published: May 2008

Studies with cell hybrids of normal diploid cells fused with tumorigenic D98AH2 (D98) cells had implicated human chromosome 11 of a normal cell as carrying tumorigenicity suppressing information. The cervical carcinoma-derived D98 (HeLa) cells contain two copies of chromosome 11. In this study, analysis of restriction fragment length polymorphism of DNA from D98 cells digested with one of nine restriction endonucleases and hybridized with five DNA probes for highly polymorphic regions on the short arm of chromosome 11 detected no heterozygosity at the insulin (INS), Harvey murine sarcoma virus 1 (HRAS1), and the β-globin cluster (HBBC) regions. The low probability of an individual being homozygous at all these loci suggests that the Nos. 11 of the D98 cells are both copies of only one of the original homologs, or at least of the short arm segment examined. This indicates that the D98 cells could express altered or lost genes associated with tumorigenicity, even if such changes were recessive. In tumorigenically suppressed hybrids the Nos. 11 of the normal cell could then be complementing this genetic defect of the D98 cells.
Human genes for insulin-like growth factors I and II and epidermal growth factor are located on 12q22→q24.1, 11p15, and 4q25→q27, respectively
Authors: Morton C.C. , Byers M.G. , Nakai H. , Bell G.I. , Shows T.B.
Published: May 2008

The genes coding for insulin-like growth factors I and II and epidermal growth factor have been localized to human chromosomes 12q22→q24.1, 11p15, and 4q25→q27, respectively.
XY sex-reversal syndrome in the domestic horse
Authors: Kent M.G. , Shoffner R.N. , Buoen L. , Weber A.F.
Published: May 2008

The XY sex-reversal syndrome occurs when a phenotypic mare is born that has the karyotype of a stallion. The syndrome is manifested by both genotypic and phenotypic heterogeneity. The sex-reversed genetic condition occurs frequently within certain pedigrees where XY females have been found and can be readily detected by chromosome karyotyping. The phenotypic spectrum ranges from the feminine mare with a reproductive tract that is within normal limits to the greatly masculinized mare. Pedigree analysis suggests that there are two modes of inheritance: (1) an X-linked recessive or autosomal sex-limited dominant transmitted through the female and (2) an autosomal sex-limited dominant or a Y chromosomal mutation with variable expression transmitted through the male.
Lithium chloride as an enhancing agent for metaphase preparations from rodent lymphocytes
Authors: Dowling P.K. , Landry, Jr. S.O.
Published: May 2008

Circulating lymphocytes of many mammals, especially rodents, have proven refractory to PHA stimulation of mitotic activity. Addition of small amounts of lithium chloride to the culture medium removes the refractoriness and increases the yield of metaphase cells 7 fold. This simple procedure makes possible the routine use of circulating lymphocytes in rodent karyology.
Chromosomal localization of human and rat Aα, Bβ, and γ fibrinogen genes by in situ hybridization
Authors: Marino M.W. , Fuller G.M. , Elder F.F.B.
Published: May 2008

In situ hybridization of radiolabeled fibrinogen cDNAs to human and rat metaphase chromosomes has shown that the genes encoding the Aα, Bβ, and γ fibrinogen subunits are syntenic in both species. Our data localize the human fibrinogen gene cluster to band q31 on chromosome 4, thereby confirming and extending previous map assignments of these genes in man. We have also assigned these genes to the q31→q34 region of rat chromosome 2. This is the first map assignment of these genes in the rat and also the first report to clearly establish linkage of the Bβ subunit gene to the Aα and γ genes in this species.
Analysis of translocations observed in three different populations
Authors: Schwartz S. , Palmer C.G. , Yu P.-L. , Boughman J.A. , Cohen M.M.
Published: May 2008

A sample of 437 reciprocal translocations was classified into three groups according to their method of ascertainment (Group I = couples with repeated abortions; Group II = karyotypically unbalanced carriers; Group III = balanced translocation heterozygotes). Statistical analysis showed that the distributions of chromosome breaks observed in the three groups could not be accounted for by chromosome arm length alone. In couples with repeated abortions, an excess of breaks in 7p, 17p, and 22q was found, whereas in the balanced translocation heterozygotes an excess of breaks was found only in 11q. An excess of breaks was found in arms 9p, 14p, 18p, 18q, 21q, and 22q in karyotypically unbalanced probands. A significant decrease of breaks in the medial chromosome regions was accompanied by a concomitant increase in the terminal regions in all groups. The three groups demonstrated different distributions of chromosome arm involvement in the observed translocations. Balanced translocation heterozygotes had the highest frequency of large (greater than the length of 4p) translocated segments and an excess in the frequency of large-large translocations, whereas karyotypically unbalanced probands had the highest frequency of small (shorter than 21q) translocations and an excess in the frequency of small-small translocations. For each type of chromosomal imbalance observed, the balanced translocation heterozygotes demonstrated the greatest potential imbalance and the karyotypically unbalanced probands the least.
An investigation of human sperm pronuclear chromosome “gaps” using scanning electron microscopy
Authors: Chernos J.E. , Rattner J.B. , Martin R.H.
Published: May 2008

A common cytogenetic finding in both Q-banded and solid Giemsa-stained preparations of pronuclear chromosomes obtained from cross-species fertilization of hamster oocytes by human sperm is the presence of a variable-length “gap” in the centromeric region. Scanning electron microscopy was used to investigate these altered chromosomal regions. The centromere in most eukaryotic organisms appears as a constricted region approximately 200–300 nm in diameter. In contrast, the gap portion of the centromeric region of pronuclear chromosomes was found to contain a chromatin fiber with a diameter of 80–150 nm. The detection of this fiber confirms that the chromosome arms are continuous, and the size of the fiber explains the gap appearance in the light photomicrographs. The morphology of the fiber is consistent with the concept that the normal chromatin packaging has been altered in varied regions within the centromere of these chromosomes.
Chromosomal localization of group-specific component by in situ hybridization
Authors: McCombs J.L. , Yang F. , Bowman B.H. , McGill J.R. , Moore C.M.
Published: May 2008

Group-specific component (GC), an alpha2-globulin plasma protein synthesized primarily in the liver, is the major vitamin D-binding protein in plasma. It has two common phenotypes, GC1 and GC2, which appear in all human populations. Using the cDNA insert containing the entire coding sequence of GC2, the GC gene was mapped to human chromosomal bands 4q13→q21.1 by in situ hybridization.
Linkage of human keratin genes
Authors: Blumenberg M. , Savtchenko E.S.
Published: May 2008

Two families of keratins, type I and type II, can be distinguished within the intermediate filament family of proteins, and at least 20 genes in the human genome code for the 20 known human keratin proteins. In epithelial intermediate filaments, keratins from both families appear to be coordinately expressed. We have screened a library of human genomic DNA and have identified several cases of linkage among homologous and heterologous pairs of keratin genes. Genes coding for type I keratins were found linked to those coding for type II keratins. Linkage was discovered also among homologous genes coding for type I keratins and among genes encoding type II keratins. In addition, we found genes coding for glycine-rich keratins linked to genes coding for those that do not contain glycine-rich regions. Our results raise the possibility that all keratin genes are linked in a single region of the human genome.
Banded chromosome studies and B chromosomes in wild-caught raccoon dogs, Nyctereutes procyonoides viverrinus
Authors: Wurster-Hill D.H. , Ward O.G. , Kada H. , Whittemore S.
Published: May 2008

Cytogenetic studies were made on Japanese raccoon dogs (Nyctereutes procyonoides viverrinus) that were caught in the wild in southern Kyushu and northern Honshu. G-banding, C-banding, acridine orange (AO) staining following BudR incorporation, and silver staining for nucleolar organizer regions (NORs) were performed on chromosomes from fibroblast cultures. Modal numbers varied from 40 to 42. The karyotype comprised 26 mediocentric and 10 acrocentric autosomes, a submetacentric X, and a minute submetacentric Y. Unpaired B chromosomes which differed in number between animals accounted for the variable modal numbers. B chromosomes stained indistinctly with G-banding but showed a variety of positive patterns with C-banding and differentiated staining with AO. NORs were observed on the telomeric ends of the long arms of chromosomes 11, 12, and 18. No cytogenetic differences were seen between the northern and southern animals.
The gene for human transforming growth factor α is on the short arm of chromosome 2
Authors: Tricoli J.V. , Nakai H. , Byers M.G. , Rall LB. , Bell G.I. , Shows T.B.
Published: May 2008

Transforming growth factor α is a polypeptide growth factor that participates in the reversible transformation of cells in vitro and is secreted by many transformed cell lines. It also shares sequence and functional homologies with epidermal growth factor. Working with a cloned cDNA probe (λhTGFl-10) and derivatives, we have mapped this gene (TGFA) to 2p13 with the use of somatic cell hybrids and in situ hybridization. This is the same region involved in the 2;8 translocations of Burkitt lymphoma. Such a rearrangement could orient c-myc (8q24) adjacent to TGFA, resulting in activation of one or both of these genes.
In situ hybridization of an acetylaminofluorene-modified probe recognized by Z-DNA antibodies in vitro
Authors: Viegas-Péquignot E. , Malfoy B. , Leng M. , Dutrillaux B. , Tchen P.
Published: May 2008

An in situ hybridization procedure, based on the chemical modification of DNA by acetylamino-fluorene (AAF), followed by a specific immunoreaction was used to localize a Z-DNA sequence isolated from the satellite DNA of Cebus appella. The AAF probe is localized on the R-band-positive heterochromatic segments of Cebus chromosomes, which strongly react with Z-DNA antibodies. The use of a nonradioactive single-stranded labeled probe confirms the reliability and the rapidity of immunochemical methods for the detection of DNA sequences on chromosomes.
Assignment of pancreatic ribonuclease gene to mouse chromosome 14
Authors: Elliott R.W. , Samuelson L.C. , Lambert M.S. , Meisler M.H.
Published: May 2008

A pancreatic ribonuclease cDNA was used as a probe for Southern blot hybridization of genomic DNA from recombinant inbred strains of mice. The results indicated that the gene coding for pancreatic ribonuclease (Rib-1) can be assigned to mouse chromosome 14. Analysis of the congenic strain BIO.D2(57N)Sn confirmed this assignment and indicated that Rib-1 is closely linked to the genes encoding the T-cell receptor alpha subunit (Tcra) and nucleoside phosphorylase-2 (Np-2).
A DNA marker for human chromosome 8 that detects alleles of differing sizes
Authors: Wood S. , Poon R. , Riddell D.C. , Royle N.J. , Hamerton J.L.
Published: May 2008

A random, unique DNA sequence has been isolated and assigned to human chromosome 8. This sequence (D8MGV1) recognizes two alleles that differ in size by 700 bp.
Chromosomal localization of leukocyte interferon gene in the pig (Sus scrofa domestica L.) by in situ hybridization
Authors: Yerle M. , Gellin J. , Echard G. , Lefevre F. , Gillois M.
Published: May 2008

Using as a probe pig genomic DNA, including the complete interferon α gene, we have mapped the leukocyte interferon gene on pig chromosome 1 by in situ hybridization. A total of 196 silver grains were noted on the 106 metaphases scored: 31% of the grains were observed on chromosome 1, and 67% of these were localized in the region 1q2.2→q2.7.
Prophase chromosome unique band sequences: definition and utilization
Authors: Lockwood D.H. , Riccardi V.M. , Johnston D.A. , Zimmerman S.O.
Published: May 2008

Extensive experience with the analysis of human prophase chromosomes and studies into the complexity of prophase banding patterns have suggested that at least some prophase chromosomal segments can be accurately identified and characterized independently of the morphology of the chromosome as a whole. The feasibility of identifying and analyzing specified prophase chromosome segments was thus investigated as an alternative approach to prophase chromosome analysis based on whole-chromosome recognition. Through the use of prophase idiograms at the 850-band stage (Francke, 1981) and a systematic comparison system, we have demonstrated that it is possible to divide the 24 human prophase idiograms into a set of 94 unique band sequences, each of which has a banding pattern that is recognizable and distinct from any other nonhomologous chromosome portion. The use of a unique band sequence approach in prophase chromosome analysis is expected to increase efficiency and sensitivity through more effective use of available banding information.
Diploid spermatids: a manifestation of spermatogenic impairment in XOSxr and T31H/+ male mice
Authors: Levy E.R. , Burgoyne P.S.
Published: May 2008

Microdensitometry of Feulgen-stained spermatogenic cell preparations from six XOSxr and four T31H/+ male mice revealed large numbers of spermatids with a diploid amount of DNA. In XOSxr mice, where the diploid spermatids usually constituted the majority of the spermatid population, there were large differences from mouse to mouse in the proportion of diploid spermatids (range, 35%-94%). There were large losses of both haploid and diploid spermatids during spermiogenesis, and the later condensed spermatids of both types were grossly misshapen. It is suggested that the omission of one meiotic division, and the other spermiogenic anomalies may be manifestations of a meiotic “quality control” mechanism that destroys the products of those pachytene spermatocytes which have unsynapsed or incompletely synapsed chromosomes.
Chromosomal evolution in Malagasy lemurs
Authors: Rumpler Y. , Ishak B. , Dutrillaux B. , Warter S. , Ratsirarson J.
Published: May 2008

The karyotypes of three Lepilemuridae species, Lepilemur mustelinus, L. edwardsi, and L. dorsalis, are described and compared to those of three Lepilemur species previously reported. The phylogenetic relationships between the six species and their presumed last common ancestor are given. The results obtained, and the comparison with other groups, strongly suggest a monophyletic origin for all Malagasy lemurs.
Assignment of a processed mouse Aprt pseudogene to the same chromosome as the functional gene
Authors: Farber R.A. , Zielinski D.
Published: May 2008

A novel genetic system has been used to demonstrate that a processed adenine phosphoribosyltransferase (Aprt) pseudogene is located on mouse chromosome 8, which is the same chromosome that carries the functional Aprt gene. A restriction fragment length polymorphism associated with the pseudogene was found to segregate concordantly with chromosome 8 in APRT– mutants of a near-diploid cell line that had lost one copy of the chromosome.
The fate of XO germ cells in the testes of XO/XY and XO/XY/XYY mouse mosaics: evidence for a spermatogenesis gene on the mouse Y chromosome
Authors: Levy E.R. , Burgoyne P.S.
Published: May 2008

A cytogenetic and histological study of nine XO/XY or XO/XY/XYY mosaic mice revealed that XO germ cells were selectively eliminated from the spermatogenic epithelium. Although the XO contribution to the bone marrow in seven mice exceeded 50%, in only two cases were significant numbers of dividing XO spermatogonia present. These XO germ cells only occasionally progressed to meiosis and then degenerated prior to first meiotic metaphase. It was concluded that the mouse Y chromosome carries a “spermatogenesis gene” (or genes) which acts autonomously in the germ cells.
Submicroscopic interstitial deletion of the X chromosome explains a complex genetic syndrome dominated by Norrie disease
Authors: Gal A. , Wieringa B. , Smeets D.F.C.M. , Bleeker-Wagemakers L. , Ropers H.H.
Published: May 2008

Norrie disease (ND), an X-linked recessive disorder, is characterized by congenital blindness followed by bulbar atrophy. We have examined a three-generation family in which ND is part of a complex X-linked syndrome with severe mental retardation, hypogonadism, growth disturbances, and increased susceptibility to infections as additional features. This syndrome is apparently due to an interstitial deletion, as evidenced by the failure of the L1.28 DNA probe (DXS7 locus, Xp11.3) to detect complementary DNA sequences on the defective X chromosome of an affected male and of several obligatory heterozygotes. Attempts to further define this deletion with other DNA probes from the proximal short arm of the X chromosome or by prometaphase chromosome analysis were unsuccessful.
Suppression of tumorigenicity in somatic cell hybrids
Authors: Klinger H.P. , Kaelbling M.
Published: May 2008

An analysis for cosegregation of chromosomes and tumorigenicity in 52 hybrids of human diploid × D98AH2 human carcinoma-derived cells reveals the consistent presence of four copies of chromosome 11 in all nontumorigenic hybrids (two from each of the parental cells) and a consistent loss of one or two copies of the 11 in all tumor cells derived from tumorigenic hybrids that grow in nude mice. In our earlier study, assays with restriction fragment length polymorphic (RFLP) markers for the cell parent origin of the chromosomes 11 in the hybrids indicated that at least one of the Nos. 11 lost in the tumor cells is from the diploid. Thus both Nos. 11 of the diploid seem to be required for complete and stable suppression of the tumorigenic phenotype. The results of the present study suggest that chromosome 2 may also carry suppressor information, but this causes only partial suppression of the tumorigenic phenotype in the absence of both Nos. 11. On the other hand, when the hybrids contain full complements of the 2 and the 11, suppression is very stable. All other chromosomes except for Nos. 1, 16, 17, 19, and 21 are clearly discordant with suppression. The latter chromosomes are not discordant often enough to allow their exclusion as possible carriers of suppressor information, particularly in the absence of RFLP evaluations. It is clear, however, that if they do carry such information it is not adequate for maintaining a stably suppressed phenotype in the absence of both Nos. 11 of the diploid.
Interordinal conservatism of chromosome banding patterns in Gallus domesticus (Galliformes) and Melopsittacus undulatus(Psittaciformes)
Authors: Ansari H.A. , Takagi N. , Sasaki M.
Published: May 2008

Chromosome banding homologies were studied between the domestic chicken, Gallus domesticus (Galliformes), and the budgerigar, Melopsittacus undulatus (Psittaciformes). In spite of large karyological differences, the G-banding patterns were found to be conserved to a considerable extent between the two species. There were some differences in C- and Hoechst 33258/Q-banding patterns.
Sex chromosome-autosome translocations in the leaf-nosed bats, family Phyllostomidae
Authors: Tucker P.K. , Bickham J.W.
Published: May 2008

Analyses of meiotic pairing and synaptonemal complexes of the composite sex chromosomes of male phyllostomid bats with X-autosome or X- and Y-autosome translocations were performed using Giemsa and silver staining procedures. Typical mammalian sex vesicles were absent in all species analyzed. Stenoder-matine species with X-autosome translocations possessed an open ring and tail configuration of the XY1Y2 trivalent. Species with both X- and Y-autosome translocations possessed a closed ring and tail configuration of the neo-XY bivalent. In both cases, the tail represented the autosomal short arm of the X paired with its homologue, either the Y2 in XY1Y2 species or the autosomal arm of the composite Y in neo-XY species. Autosomal pairing of the composite sex bivalent in neo-XY species replaced an association between the original X and Y in late prophase I. The absence of a sex vesicle, the unusual pairing configurations of the composite sex chromosomes, and the presumed absence of meiotic nondisjunction in these species is discussed in light of current hypotheses of sex chromosome behavior in male gametogenesis in mammals.
Evolution of the ZZ/ZW system in Leporinus (Pisces, Anostomidae)
Authors: Galetti, Jr. P.M. , Foresti F.
Published: May 2008

The presence of constitutive heterochromatin on the Z and W chromosomes of four Leporinus species (L. elongatus, L. ohtusidens, L. reinhardti, and Leporinus sp.) was studied by C -banding. A hypothetical role of the heterochromatin in the differentiation of the sex determination system in these fishes is proposed.
Owl monkey gene mapping: the assignment of gene loci for catalase, β-globin gene cluster, HRAS1, insulin, and parathyroid hormone
Authors: Ma N.S.F. , Gerhard D.S. , Housman D.E. , Orkin S. , Bruns G.
Published: May 2008

Using somatic cell genetics and Southern blot hybridization, we have mapped five structural genes in the owl monkey, coding for catalase (CAT), the β-globin gene cluster (HBBC), c-Ha-ras 1 (HRAS1), insulin (INS), and parathyroid hormone (PTH). All five loci are mapped to chromosome 19 of karyotype VI (2n = 49,50) of the owl monkey; CAT, HBBC, INS, and PTH can be assigned to chromosome 4 of karyotype V (2n = 46), while CAT and HBBC can be assigned to chromosome 2 of karyotype III (2n = 53). Using in situ hybridization, the CAT gene was precisely mapped on the mid-region and the β-globin gene cluster on the telomeric end of chromosome 2q(K-ΠI). Our results provide significant insight into the evolutionary history of these gene loci. While these loci are separated into at least two major segments in rodents such as the mouse, our results suggest conservation of a single chromosome arm among higher primates.
An evolutionarily conserved early replicating segment on the sex chromosomes of man and the great apes
Authors: Weber B. , Schempp W. , Wiesner H.
Published: May 2008

Replication studies on prometaphase chromosomes of man, the chimpanzee, the pygmy chimpanzee, the gorilla, and the orangutan reveal great interspecific homologies between the autosomes. The early replicating X chromosomes clearly show a high degree of conservation of both the pattern and the time course of replication. An early replicating segment on the short arm of the X chromosomes of man (Xp22.3) which escapes inactivation can be found on the X chromosomes of the great apes as well. Furthermore, the most early replicating segment on the Y chromosomes of all species tested appears to be homologous to this segment on the X chromosomes. Therefore, these early replicating segments in the great apes may correspond to the pseudoautosomal segment proposed to exist in man. From further cytogenetic characterization of the Y chromosomes it is evident that structural alterations have resulted in an extreme divergence in both the euchromatic and heterochromatic parts. It is assumed, therefore, that, in contrast to the X chromosomes, the Y chromosomes have undergone a rapid evolution within the higher primates.
Chromosome 1 localization of the human alpha-L-fucosidase structural gene with a homologous site on chromosome 2
Authors: Fowler M.L. , Nakai H. , Byers M.G. , Fukushima H. , Eddy R.L. , Henry W.M. , Haley L.L. , O’Brien J.S. , Shows T.B.
Published: May 2008

Two cDNA clones coding for human α-L-fucosidase, one from the coding region and the other primarily from the 3’ untranslated region, were used to map the location of the α-L-fucosidase gene. Southern filter analysis of somatic cell hybrid lines mapped the structural gene to the short arm of human chromosome 1, and in situ hybridization to chromosomes of human leukocytes further localized the homologous area to the 1p36.1→p34.1 region, with the most likely location being the distal region of lp34. Further Southern filter analysis detected a second site of homology on chromosome 2. This α-L-fucosidase-like site has been designated FUCA1L.
Statistical decision rules concerning synteny or independence between markers
Authors: Chevalet C. , Corpet F.
Published: May 2008

Data on the segregation of human markers in somatic hybrids between permanent rodent cell lines and primary human cells were gathered and statistically analyzed, using various criteria of association. The analysis provides evidence that human chromosomes do not segregate independently in somatic cell hybrids. A statistical decision rule concerning synteny or independence between markers is proposed, and its utility in developing the gene maps of other species by means of somatic cell hybridization is explored.
Chromosomal localization of the human oncogene ERBA2
Authors: Gosden J.R. , Middleton P.G. , Rout D. , De Angelis C.
Published: May 2008

The human ERBA2 gene has been mapped to chromosome 17q21.3 by in situ hybridization. A second hybridization site at 17q25 was greatly reduced by high stringency washes, indicating the presence of an additional member of the ERBA2 family at this location. Southern blot hybridization using identical conditions did not reveal additional bands, and hybridizations done at sufficiently low stringency to reveal further bands produced multiple bands rather than the single additional band expected from the in situ results. Direct comparisons of in situ and Southern hybridizations should therefore be treated with caution. The location of these two oncogenes may be significant in cases of acute promyelocytic leukaemia and acute nonlymphocytic leukaemia.
Meiotic association between the XY chromosomes and the autosomal quadrivalent of a reciprocal translocation in two infertile men, 46, XY, t(19;22) and 46, XY, t(17;21)
Authors: Gabriel-Robez O. , Ratomponirina C. , Dutrillaux B. , Carré-Pigeon F. , Rumpler Y.
Published: May 2008

An electron microscopy study of synaptonemal complexes in two men carrying reciprocal translocations, a t(19;22) and a t(17;21), is reported. It is shown that a delay in synapsis affects the segments corresponding to the short arms of the acrocentrics involved in the formation of quadrivalents. This appears to provoke an interaction with the sex bivalent which could lead to a failure of spermatogenesis. A study of the literature comparing reciprocal translocations that do and do not involve acrocentrics in sterile and fertile men shows the existence of a significant association between the presence of an acrocentric in the rearrangement and sterility. These results on reciprocal translocations involving at least one acrocentric chromosome correspond to those obtained in cases of Robertsonian translocations.
Synaptonemal complexes in Gerbillidae: probable role of intercalated heterochromatin in gonosome-autosome translocations
Authors: Ratomponirina C. , Viegas-Péquignot E. , Dutrillaux B. , Petter F. , Rumpler Y.
Published: May 2008

A study of sex chromosomes and synaptonemal complexes in male specimens of Gerbillus chiesmaní, G. nigeriae, G. hoogstrali, and Taterillus pygargus is reported. In each of these Gerbillidae species there are two or three translocations of autosomes with X and Y chromosomes. Analysis of mitotic chromosomes consistently shows the presence of constitutive heterochromatin on the der t(X;autosome) at the X-autosome junction and on the der t(Y;autosome). Analysis of the synaptonemal complexes shows the existence of an unusual structure, lightly stained, at the X-autosome junction and at the Y-autosome junction, which is probably heterochromatic in nature, thus corresponding to the mitotic patterns. This heterochromatin separates the autosomal and gonosomal segments, which behave independently and normally. By analogy with findings from humans and other mammals, a general hypothesis is proposed on the role of intercalated heterochromatin between translocated gonosomes and autosomes. This hypothesis explains why the pathological consequences of these translocations may be very different in males and females. The role of intercalated heterochromatin would be to avoid the pathological consequences of gonosome-autosome translocations resulting from inactivation of the sex chromosomes in female somatic cells and male germinal cells.
Chromosomal homoeologies in hamster species of the genus Phodopus (Rodentia, Cricetinae)
Authors: Schmid M. , Haaf T. , Weis H. , Schempp W.
Published: May 2008

The karyotypes of the two hamster species Phodopus sungorus and P. roborovska were analyzed with several banding techniques and compared. The homoeologies found between all chromosomes led to the proposal of the most likely common ancestral karyotype of these two species. The differences in the karyotypes were found to be a result of seven independent centric fusions, three inversions, and one possible telomeric fusion, as well as changes in the quantity and DNA-base pair composition of the constitutive heterochromatin.
Detection of two TaqI polymorphisms in the VTR region of the human HRAS1 oncogene
Authors: Pierotti M.A. , Radice P. , Biunno I. , Borrello M.G. , Cattadori M.R. , Della Porta G.
Published: May 2008

Restriction enzyme analysis of the variable tandem repetition (VTR) region of the human HRAS1 oncogene revealed two Taql polymorphisms. The first polymorphism overlaps that detected with MspliHpaW restriction enzymes and is due to a variable number of repeat units which form the VTR region at the 3’ end of the oncogene. The second polymorphism appears to be due to two new Taql restriction sites created within the VTR region itself. This novel polymorphism was detected in 26 of 145 human DNA samples and was found to segregate in a Mendelian fashion.
The cellular homologue of the transforming gene of SKV avian retrovirus maps to human chromosome region 1q22→q24
Authors: Chaganti R.S.K. , Balazs I. , Jhanwar S.C. , Murty V.V.V.S. , Koduru P.R.K. , Grzeschik K.-H. , Stavnezer E.
Published: May 2008

We report the chromosomal localization of the cellular oncogene SKI, the putative oncogene of the Sloan-Kettering viruses (SKVs), a group of transforming retro viruses that had been isolated from chicken embryo cells infected with the avian leukosis virus tdB77. Southern blot analysis of DNA from mouse × human somatic cell hybrids with the v-SKI probe established synteny with chromosome 1 but excluding the region 1pter→q21. In situ hybridization of the same probe both to human spermatocyte pachytene and lymphocyte metaphase chromosomes enabled precise localization of the gene to the region 1q22→q24, a region that frequently is involved in translocations and other rearrangements in diverse human tumor types. In situ hybridization studies of metaphase spreads from a small noncleaved cell lymphoma that exhibited a t(1; 14)(q21 ;q32) translocation showed that SKI translocates to the der(14) chromosome. Cytogenetic analysis of 65 prospectively ascertained non-Hodgkin’s lymphomas revealed that the SKI region undergoes nonrandom breakage leading to translocations. Further analysis of the chromosome breaks in this group of lymphomas suggested that those involving the SKI site probably are of importance in tumor progression.
Recombination nodules in the oocytes of the chicken, Gallus domesticus
Authors: Rahn M.I. , Solari A.J.
Published: May 2008

Chicken oocytes at pachytene were processed with the microspreading technique (Moses, 1977), and their synaptonemal complex (SC) complements were analyzed by electron microscopy. Ellipsoidal nodules, 140 × 120 nm in diameter, were associated with the central space of synaptonemal complexes. The average number of nodules per pachytene oocyte was 57.5. The number of nodules per bivalent showed a clear linear relationship with SC length, except for the microchromosomes, which showed a single obligatory nodule. The distribution of nodules along the 10 longest SCs was nonrandom, with low frequencies in the vicinity of kinetochores and high frequencies near the telomeres. The microchromosomes showed a single nodule whose average location was 1.21 µm from the kinetochore. In the ZW pair there was a single nodule whose average location was 0.31 µm from the paired telomeres and not more than 0.65 µm from them. The total number of nodules per cell and the number of nodules in each of the five major bivalents showed good agreement with the total number of chiasmata and the number of chiasmata of the major bivalents of roosters. Thus, these nodules share the characteristics of recombination nodules described in other organisms. The single, obligatory, strictly localized recombination nodule found in the pairing end of the ZW pair strongly suggests that recombination between the Z and W chromosomes in the female chicken is a regular process that may be similar to the obligatory recombination between the pairing ends of the human X and Y chromosomes that was recently described in studies using DNA probes.
A new type of nonhomologous synapsis in T(X;4)1R1 translocation male mice
Authors: Ashley T. , Russell L.B.
Published: May 2008

The synaptonemal complexes of T(X;4)1R1 (abbreviated Rl) translocation heterozygotes have been examined by electron microscopy and compared with those of two X-7 translocations: R5 and R6. The X chromosome breakpoint of Rl is estimated to lie between 78 and 82% from the proximal end of the X, in the same general region as the R5 and R6 breakpoints. The position of the autosomal breakpoint of Rl, like that of R6, is about 30% from the proximal end of the respective autosome. Rl is also similar to R6 in that there is extensive nonhomologous synapsis both in quadrivalents and heteromorphic bivalents. We have recently found that the location of breakpoints with respect to the position of the G-bands appears to be related to the synaptic behavior seen in translocation heterozygotes. If both breaks of a reciprocal translocation lie in G-light bands, as was the case with R5, synapsis is confined to homology. However, if one break lies in or immediately adjacent to a G-dark band, there is nonhomologous synapsis, as occurs with Rl and R6. Comparison of the synaptic behavior of Rl with R5 and R6 leads to the conclusion that this G-band-related nonhomologous synapsis is of a different type than the “synaptic adjustment” phenomenon that has been described by Moses (1977a). This G-band-related nonhomologous synapsis is not substage-specific, but competes with homologous synapsis during zygotene-early pachytene.
Centromere pattern in different mouse seminiferous tubule cells
Authors: del Mazo J. , Martín-Sempere M.J. , Kremer L. , Avila J.
Published: May 2008

Centromere arrangement in different mouse seminiferous tubule cells was analyzed using an anticentromere antiserum from a patient with the CREST syndrome of scleroderma. A peptide of 18 kd was recognized by this serum on immunoblotting of mouse nuclear proteins from seminiferous tubule cells. In the cells studied by immunofluorescence, different patterns of centromere arrangement were observed. A speckled arrangement of centromeres was found in spermatogonia, double spots corresponding to meiotic bivalents were found in pachytene cells, and clusters of a haploid numer of centromeres were found in early and acrosome phase spermatids. In Sertoli cells, only three centromeric spots were detected, corresponding to the nucleolar organizer chromosome pairs. A relationship between the functional stage of the cell and the arrangement of and conformational changes in the centromeres is considered.
Easy transfer of selected mitoses from light to electron microscopy
Authors: Messier P.-E. , Jean P. , Richer C.-L.
Published: May 2008

A method is described whereby any given chromosome spread selected by light microscopy can be transferred to a grid and studied by electron microscopy.
Localization of the human oestrogen receptor gene to chromosome 6q24→q27 by in situ hybridization
Authors: Gosden J.R. , Middleton P.G. , Rout D.
Published: May 2008

The oestrogen receptor gene (ER) was mapped by in situ hybridization. Using a human cDNA probe containing the coding sequence for the oestrogen receptor, the gene was localized to 6q24→q27.
Mapping of human cellular retinol-binding protein to chromosome 3
Authors: Colantuoni V. , Rocchi M. , Roncuzzi L. , Romeo G.
Published: May 2008

The gene for human cellular retinol-binding protein (CRBP) has been assigned to chromosome 3, based on an analysis of genomic DNA from human-hamster somatic cell hybrids using a cDNA probe for CRBP.
Ethanol-induced aneuploidy in male germ cells of the mouse
Authors: Hunt P.A.
Published: May 2008

The administration of alcohol to male mice 2–6 h before the preparation of second meiotic metaphases from testes resulted in an approximately six-fold increase in aneuploidy. The timing employed indicates that the observed chromosome abnormalities were a result of nondisjunction and/or anaphase lagging at the first meiotic division. A similar effect has been described in the female mouse; however, the present results suggest that the aneuploidy-inducing effect of ethanol may be substantially greater in the female than in the male.
Folate-sensitive fragile sites on the X-chromosome heterochromatin of the Indian mole rat, Nesokia indica
Authors: Tewari R. , Juyal R.C. , Thelma B.K. , Das B.C. , Rao S.R.V.
Published: May 2008

Folate-sensitive fragile sites have been demonstrated on the X chromosome of the Indian mole rat, Nesokia indica (subfamily Murinae), utilizing peripheral blood lymphocyte cultures. All normal female individuals expressed fragile sites on the constitutive heterochromatic long arm of one of their two X chromosomes (heterozygous expression); in contrast, no fragile sites were found on the single X chromosome of normal males. Preferential transmission of the maternal fragile X to the daughters is therefore suggested. Four sites have been detected so far: fra Xq1, fra Xq2, fra Xq3, and fra Xc (centromeric). It is significant that their location corresponds to the regions where constitutive heterochromatic deletions occur that result in a variety of polymorphic X chromosomes in natural populations of Nesokia. Thus there is a correlation between fragile sites, deletion sites, and karyotypic changes. In individuals that did not reproduce in the laboratory, there were more fragile sites on both X chromosomes of the females (homozygous/double heterozygous expression) and also on the X of the males (hemizygous expression). This difference in fragile site expression from the normal situation could be attributed to one or more new mutations. However, the mechanism by which fragile sites influence reproductive performance is unclear.
DNase I hypersensitive sites along the XY bivalent at meiosis in man include the XpYp pairing region
Authors: Chandley A.C. , McBeath S.
Published: May 2008

The DNase I nick translation technique has been applied to human meiotic chromosomes in situ. At metaphase I, distinct hot spots of autoradiographic labelling occur at three positions along the XY bivalent; over the Xpter and Ypter pairing tips, over Xq and Yq terminal/telomeric segments, and at a site just below the centromere in Xq. The latter might correspond to the postulated human inactivation centre. Compared with somatic chromosomes, human meiotic bivalents in general exhibit a greater accessibility to DNase I. Site-specific conformational changes in the DNA between somatic and germ line cells could be a necessary prerequisite for crossing-over.
Comparison of cytologic and genetic distances between long arm subtelomeric markers of human autosome 14 suggests uneven distribution of crossing-over
Authors: Purrello M. , Alhadeff B. , Whittington E. , Buckton K.E. , Daniel A. , Arnaud P. , Rocchi M. , Archidiacono N. , Filippi G. , Siniscalco M.
Published: May 2008

The analysis of two rodent × human somatic cell hybrids, carrying different inborn translocations of the human chromosome 14 long arm, has permitted us to narrow down the localization of the structural locus for alpha-1-antitrypsin (PI) to band 14q32.1, proximally to the highly polymorphic DNA locus D14S1 which has been localized by previous studies between 14q32.1 and 14q32.2. These data, evaluated in conjunction with other published information, suggest that the D14S1 locus is cytologically equidistant from both the PI locus and the complex locus for the immunoglobulin heavy chains (IGH) but, genetically, it appears much closer to the latter since the recombination frequency reported between the IGH complex and PI is six times greater than that between the IGH complex and D14S1 (lod score peaks respectively at 26% and 4% with narrow fiducial limits). The present report adds further strength to the frequently proposed hypothesis of a nonlinear relationship between cytologic and genetic distances of human genes. The possibility that this phenomenon may be a feature of frequent occurrence throughout the entire human genome is discussed.
Mapping of the oncogenes Myc, Sis, and int-1 to the distal part of mouse chromosome 15
Authors: Adolph S. , Bartram C.R. , Hameister H.
Published: May 2008

Two proto-oncogenes, Myc and Sis, as well as a putative mouse oncogene, int-1, were localized by in situ hybridization to the distal third of mouse chromosome 15. The respective loci of these genes map to different cytogenetic sites with Myc in 15D2-D3, Sis in 15E, and int-1 in 15F1-F3. These data may be of considerable impact as to the correlation of mouse neoplasias with chromosomal aberrations involving chromosome 15.