bluuebunny/crossref_metadata_2025 huggingface dataset:
Assignment of the gene coding for both the β-subunit of prolyl 4-hydroxylase and the enzyme disulfide isomerase to human chromosome region 17p11→qter
Authors: Pajunen L. , Myllylä R. , Helaakoski T. , Pihlajaniemi T. , Tasanen K. , Höyhtyä M. , Tryggvason K. , Solomon E. , Kivirikko K.I.
Published: May 2008

The chromosomal location of the human gene coding for both the β-subunit of prolyl 4-hydroxylase (P4HB) and the enzyme disulfide isomerase (PDI) was determined using mouse × human somatic cell hybrids and three different methods for identifying either the human P4HB/PDI protein or the respective gene: immunoblotting with species-specific monoclonal antibodies; radioimmunoassay with species-specific polyclonal antibodies; and (3) Southern blotting after cleavage of the DNA with EcoRI, HindIII, or BamHI, followed by hybridization with a mixture of two cDNA probes for human P4HB. All three methods gave identical data, demonstrating complete cosegregation of the human protein or its gene in all 17 cell hybrids tested with human chromosome 17. A cell hybrid lacking an intact chromosome 17 localized the gene to 17p11→qter.
Assignment of the human protein C gene (PROC) to chromosome region 2q14→q21 by in situ hybridization
Authors: Kato A. , Miura O. , Sumi Y. , Aoki N.
Published: May 2008

The protein C gene (PROC) was mapped by in situ hybridization. A genomic DNA probe containing the first three exons was 3H-labeled by nick translation, and this was then hybridized in situ to human chromosome preparations. The results localize the gene to 2q14→q21.
Meiotic segregation of human sperm chromosomes in translocation heterozygotes: report of a t(9;10)(q34;q11) and a review of the literature
Authors: Martin R.H.
Published: May 2008

Meiotic segregation products were studied in sperm from a man who was heterozygous for a reciprocal translocation, t(9;10)(q34;ql 1). A total of 171 sperm chromosome complements were studied by in vitro fertilization of hamster eggs. All possible 2:2 and 3:1 meiotic segregations were observed with the following frequencies: alternate, 41%; adjacent-1, 48%; adjacent-2, 5%; 3:1, 6%. Within alternate segregations, the number of normal sperm (35) was not significantly different from the number of sperm carrying a balanced form of the translocation (33), as expected. The proportion of sperm with an unbalanced form of the translocation was 60%. There was no evidence for an interchromosomal effect, since the frequencies of numerical (8%) and structural (15%) chromosomal abnormalities (both unrelated to the translocation) were within the normal range of control donors. The literature on a total of 10 translocation heterozygotes studied by sperm chromosome analysis was reviewed.
Human NORs show correlation between transcriptional activity, DNase I sensitivity, and hypomethylation
Authors: Ferraro M. , Prantera G.
Published: May 2008

Active human ribosomal gene clusters (NORs) are distinguishable from inactive ones by silver staining. By sequentially applying deoxyribonuclease I (DNase I)-directed in situ nick-translation and silver staining to fixed chromosome preparations, we found that active NORs are more sensitive to DNase I than inactive ones. Use of the two restriction isoschizomeres Mspl and Hpall to modify the nick-translation technique showed that active NORs are significantly less methylated than inactive ones. Taken as a whole, our results indicate that ribosomal gene activity. DNase I sensitivity, and DNA methylation are closely interrelated.
Somatic cell mapping and restriction fragment analysis of bovine alpha and beta interferon gene families
Authors: Adkison L.R. , Leung D.W. , Womack J.E.
Published: May 2008

DNA from bovine × hamster hybrid cells preferentially segregating bovine chromosomes has been analyzed by blot hybridization with alpha and beta interferon probes. Retention or loss of bovine interferon genes was compared to segregation of bovine isozyme loci representing previously described syntenic groups. Families of bovine alpha (IFNA) and beta (IFNB) interferon genes were segregated in concordance with each other and with aconitase-1 (ACO1) on bovine syntenic group U18. This syntenic relationship is conserved on human chromosome 9p and on the portion of mouse chromosome 4 proximal to the centromere. In addition, cattle restriction fragment length polymorphisms were identified with both IFNA and IFNB probes. Of particular interest is a polymorphism apparently due to duplication of IFNB genes.
Human α2-HS-glycoprotein localized to 3q27→q29 by in situ hybridization
Authors: Magnuson V.L. , McCombs J.L. , Lee C.-C. , Yang F. , Bowman B.H. , McGill J.R.
Published: May 2008

Human plasma protein α2-HS-glycoprotein (AHSG) is composed of two polypeptide chains, A and B, encoded by a single mRNA. Southern blot analysis of mouse × human somatic cell hybrids has mapped the AHSG gene to human chromosome 3 in the region 3q21→qter (Lee et al., 1987). Using a recombinant plasmid containing a 1,538 bp insert spanning the entire AHSG coding region, AHSG was localized to chromosomal bands 3q27→q29 by in situ hybridization.
Evidence for in situ amplification of a germ line homogeneously staining region in the mouse
Authors: Boldyreff B. , Winking H. , Weith A. , Traut W.
Published: May 2008

A cloned DNA sequence that is specific for a germ line homogeneously staining region (HSR) on chromosome 1 of the mouse was found to be homologous to a single copy sequence in non-HSR mice. By in situ hybridization, the sequence in non-HSR mice was localized to approximately the same site as the insertion site of the HSR on chromosome 1 of HSR mice, indicating in situ amplification of the HSR.
DNA analysis by flow cytometry
Authors: Kent M. , Chandler R. , Wachtel S.
Published: May 2008

Accurate quantification of DNA from cells of several species is possible with flow cytometry. When one species is used as a reference, cytometric readings from two or more different species can be compared to obtain relative percent DNA or DNA indices. Differences in DNA from the male and female of the same species also can be measured. The method allows rapid screening of chromosomal abnormalities among large clinical populations, and evaluation of errors of sex determination such as XY sex reversal.
X-linked lymphoproliferative disease: a karyotype analysis
Authors: Harris A. , Docherty Z.
Published: May 2008

X-linked lymphoproliferative disease (XLP) is triggered by Epstein-Barr virus. This virus is also associated with Burkitt lymphoma, a tumor that carries specific chromosome translocations. No such chromosome translocations have been observed in an analysis of XLP-derived cell lines. One XLP patient was found also to have Klinefelter syndrome, having inherited two copies of his maternal XLP-carrying X chromosome.
Human corticotropin releasing hormone gene is located on the long arm of chromosome 8
Authors: Arbiser J.L. , Morton C.C. , Bruns G.A.P. , Majzoub J.A.
Published: May 2008

The chromosomal locus of the human corticotropin releasing hormone (hCRH) gene was assigned to chromosome 8 using Southern blot analysis of human × rodent cell hybrids and was localized to band 8q 13 using in situ hybridization to metaphase chromosomes. The absence of secondary hybridization strongly suggests that hypothalamic and placental CRH are transcribed from the same gene.
Human chromosome banding specific for electron microscopy
Authors: Drouin R. , Messier P.-E. , Richer C.-L.
Published: May 2008

Electron microscopy (EM) provides much higher resolution than that obtained with light microscopy (LM). Until now, however, no chromosome banding procedure specifically adapted for EM was available. To produce an easy and reproducible banding method that would allow accurate chromosome identification, we investigated the applicability of an immunochemical method. BrdU-substituted chromosomal regions can be accurately visualized by applying a monoclonal antibody against BrdU, followed by a gold-tagged secondary antibody. Since BrdU is incorporated during the last part of the S-phase, regions of darkly stained G- and C-bands are substituted. A characteristic C-banding pattern is revealed, and the G-banding obtained is sharp and allows discrimination between subbands. Its similarity with the classical G-banding observed by LM makes it easy to interpret and facilitates karyotyping.
Localization of mouse phenylalanine hydroxylase locus on chromosome 10
Authors: Ledley F.D. , Ledbetter S.A. , Ledbetter D.H. , Woo S.L.C.
Published: May 2008

Mo use phenylalanine hydroxylase has been localized on chromosome 10C2→D1 by in situ hybridization using a mouse phenylalanine hydroxylase cDNA clone. This locus is distinct from the hyperphenylalaninemia locus on chromosome 14 and the locus for tyrosine hydroxylase on chromosome 7.
The human liver-type pyruvate kinase (PKL) gene is on chromosome 1 at band q21
Authors: Satoh H. , Tani K. , Yoshida M.C. , Sasaki M. , Miwa S. , Fujii H.
Published: May 2008

Pyruvate kinase (PK) is an important enzyme for ATP production in the glycolytic pathway. Deficiency of this enzyme in erythrocytes is characterized by hemolytic anemia. Using in situ hybridization, we have mapped the human liver-type pyruvate kinase gene (PKL) to band q21 of chromosome 1.
A fertile mule and hinny in China
Authors: Rong R. , Chandley A.C. , Song J. , McBeath S. , Tan P.P. , Bai Q. , Speed R.M.
Published: May 2008

Anecdotal reports of fertility in female mules (jack donkey × mare) and hinnies (stallion × jenny donkey) have appeared in the literature over the years, but scientists have generally regarded them with scepticism. The fact that some of these hybrids can come into estrous and ovulate makes fertility conceivable, given that opportunity for mating arises. In China, where mules are bred extensively for work on the farms, a fertile female mule and a fertile female hinny have now been verified by chromosomal investigation. Each had mated with a donkey and produced a filly foal. The foals show unique hybrid karyotypes different from the mule’s or hinny’s and different from each other’s. The studies make it clear that mule and hinny fertility, at least for the female hybrid, is a real possibility.
Clarification of chromosomal abnormalities associated with sexual ambiguity by studies with Y-chromosomal DNA sequences
Authors: Stalvey J.R.D. , Erickson R.P. , Dasouki M. , Glover T. , Shokir M.
Published: May 2008

Cases of gonadal dysgenesis, both Turner syndrome and mixed, were studied with Y centromeric and short-arm probes. The Y-centromeric alphoid repeat clone, Y97, allowed sensitive detection of Y-chromosomal material in marker chromosomes or mosaics by in situ analysis or Southern hybridization with purified DNA. The Y short-arm probe, p75/79, allowed detection of sequences normally associated with proximal Yp by Southern analysis. The presence of DNA fragments characteristic of Yp correlates well with partial male sexual differentiation in the cases of mixed gonadal dysgenesis. Thus, the combined use of molecular and cytogenetic techniques has proven to be a powerful approach to the analysis of chromosomal sex disorders.
Isolation and characterization of alphoid DNA sequences specific for the pericentric regions of chromosomes 4, 5, 9, and 19
Authors: Hulsebos T. , Schonk D. , van Dalen I. , Coerwinkel-Driessen M. , Schepens J. , Ropers H.H. , Wieringa B.
Published: May 2008

We have cloned and characterized two distinct types of alphoid DNA elements. Probe pG-Xbal 1/340 was obtained by random cloning of human satellite DNA and contains two basic units with overall 88% homology to the 171 -bp consensus alphoid sequence. pG-Xball/340-like elements are represented about 2,000-4,000 times in the haploid genome and, by in situ hybridization, are found exclusively at the primary constrictions of chromosomes 4 and 9. Probe pG-A16 was cloned from a chromosome 19-specific cosmid library and represents a 2.25-kb higher-order DNA element which is present at roughly 75-150 copies per haploid genome and which hybridizes to the centromeres of chromosomes 5 and 19. Using the pG-A16 probe, further genetic and physical dissection of the central area of chromosome 19 can be envisaged.
Centric fission in the karyotype of a mother-daughter pair of donkeys (Equus asinus)
Authors: Trommershausen-Bowling A. , Millon L.
Published: May 2008

A mother-daughter pair of donkeys was found to have identical karyotypes with a diploid number of 63. The difference from the species karyotype could be explained by a centric fission event in the third largest autosomal pair.
Somatic cell mapping and restriction fragment analysis of bovine genes for fibronectin and gamma crystallin
Authors: Adkison L.R. , Skow L.C. , Thomas T.L. , Petrash M. , Womack J.E.
Published: May 2008

DNAs from cow-hamster and cow-mouse somatic hybrid cells segregating bovine chromosomes have been analyzed by Southern blotting and hybridization with human fibronectin and gamma crystallin probes. Concordancy of retention of these bovine genes was compared to cattle isozyme loci representing previously described syntenic groups. Bovine fibronectin (FN1) and gamma crystallin (CRYG) fragments were concordant with each other and with isocitrate dehydrogenase 1 (IDHl), representing the bovine syntenic group U17. The syntenic relationship of these genes is conserved on human chromosome 2q and also on mouse chromosome 1. In addition, bovine RFLPs were identified with both fibronectin and gamma crystallin probes. These polymorphisms will be used to study recombination between the syntenic loci in pedigreed herds and to mark a segment of the bovine genome that is likely homologous to the Lsh region of mouse chromosome 1, which confers resistance in mice to several intracellular parasites.
Pachytene analysis in males heterozygous for a familial translocation (9;12;13) (q22; q22; q32) ascertained through a child with partial trisomy 9
Authors: Johannisson R. , Löhrs U. , Passarge E.
Published: May 2008

A family with four male and three female heterozygotes for a three-way translocation (9; 12; 13) (q22; q22; q32) in three generations was ascertained through a chromosomally unbalanced newborn with an additional derivative chromosome 9 resulting from nondisj unction. Three heterozygous males from two generations with apparent differences in their fertility status were investigated using pachytene spreads and testicular histology. Pachytene analysis in all three individuals, the fertile (II-2) as well as the subfertile (III–7) and infertile (III–9), showed a hexavalent with central nonpairing around the translocation breakpoints in nearly all spermatocytes. Thus, the observed hexavalen configurations in pachytene do not seem to have caused impaired fertility. This rather may have been the result of sperm carrying unbalanced chromosome sets. However, the observed difference in fertility between the heterozygous fertile male in generation II and his two heterozygous sons remains unexplained.
Fragile X expression in thymidine-prototrophic and auxotrophic human-mouse somatic cell hybrids under low and high thymidylate stress conditions
Authors: Hori T. , Takahashi E. , Tsuji H. , Tsuji S. , Murata M.
Published: May 2008

Expression of the fragile X site fra(X)(q27.3) was studied in thymidine-prototrophic and auxotrophic human-mouse somatic cell hybrids. In these cells, low thymidylate stress, achieved by 5-fluoro-2’-deoxyuridine (FdU) treatment and by limiting the exogenous supply of thymidine (dT), induced fragile X expression. High thymidylate stress, produced by supplying excess amounts of dT, was also effective in inducing fragile X expression, even in a hybrid clone that retained a fragile X chromosome as the only human chromosome; addition of deoxycytidine (dC) completely abolished this effect. In contrast, 5-bromo-2’-deoxyuridine (BrdU) did not induce fragile X expression. Cell-cycle analysis of BrdU-deprived thymidine-auxotrophic hybrid cells indicated that one round of DNA replication under thymidylate stress conditions is sufficient for fragile X expression. Our results suggest that the expression is an intrinsic property of the fragile site itself, which is believed to be composed of replicon clusters with pyrimidine-rich DNA sequence(s).
The creeping vole, Microtus oregoni: karyotype and sex-chromosome differences between two geographical populations
Authors: Libbus B.L. , Johnson L.A.
Published: May 2008

The G-banded karyotype of the creeping vole, Microtus oregoni, prepared from animals trapped in Oregon and Washington, is presented. The two populations had similar autosomal banding patterns but exhibited striking differences in their sex chromosomes. The X chromosome of voles captured in Oregon was 39% longer than that of voles trapped in Washington. The length difference was primarily due to an increase in size of light G-bands, which, in both populations, comprised large segments of the X chromosome. On C-banding, the X chromosome exhibited major blocks of constitutive heterochromatin corresponding to the light G-bands. In contrast, the Y chromosome of the Oregon voles was 24% shorter than that of the Washington voles and lacked the short arm and some terminal bands present in the Washington voles.
Evidence for a compensatory mechanism regulating Ag-NOR activity in families with de novo 21;21 translocation Down syndrome
Authors: Nikoliš J. , Kekič V.
Published: May 2008

Nucleolus organizing region (NOR) activity in seven probands with Down syndrome due to a de novo (21 ;21) trans-location and their parents was analyzed on the basis of total Ag-NOR size per cell, mean Ag-NOR size per cell (Xc), mean Ag-NOR size per acrocentic (Xa), and the characteristic Ag-NOR number of each subject. The results showed intercellular variations in total Ag-NOR size per cell in all subjects, as well as interindividual variations in mean Ag-NOR size per cell. When the subjects were grouped according to their characteristic Ag-NOR number and the mean Ag-NOR size per cell for each group (GXc) and the mean Ag-NOR size per acrocentric for each group (GXJ were calculated, a number of interesting and significant correlations were found: (1) GXc correlated perfectly with the group’s characteristic Ag-NOR number, (2) GXa varied inversely with the group’s characteristic Ag-NOR number, and (3) GXc and GXa varied inversely with each other. These results suggest that if the Ag-NOR number of a cell decreases, the total NOR activity of the cell also decreases, but the NOR activity of its chromosomes increases. This finding supports the existence of a compensatory mechanism that regulates NOR activity on the cellular level.
Assignment of the human α2-plasmin inhibitor gene (PLI) to chromosome region 18p11.1→q11.2 by in situ hybridization
Authors: Kato A. , Nakamura Y. , Miura O. , Hirosawa S. , Sumi Y. , Aoki N.
Published: May 2008

The human α2-plasmin inhibitor gene (PLI) was mapped by in situ hybridization using a genomic DNA probe which contained exons coding for the signal peptide and a portion of the mature protein. The results allowed the chromosome localization of the gene to 18p11.1→q11.2.
Comparative cytogenetics of the primitive frog, Leiopelma archeyi (Anura, Leiopelmatidae)
Authors: Green D.M. , Sharbel T.F.
Published: May 2008

Chromosomally, Leiopelma archeyi is extremely similar to L. hamiltoni, a closely related species. Both have 2n = 18 chromosomes. Contrary to a previous report, the nucleolar organizer region and secondary constriction in L. archeyi are near the telomere of the smallest, telocentric chromosome, as in L. hamiltoni. The arm-length ratios of all chromosomes are virtually identical in the two species, expect for chromosomes 2 and 3, which show evidence of a past translocation. However, L. archeyi has much less heterochromatin than does L. hamiltoni, and, unlike L. hamiltoni, heteromorphic sex chromosomes are not discernable. These frogs demonstrate two stages in the evolution of sex-chromosome differentiation related to the extent of heterochromatin accumulation.
Localization of the processed gene for human ceruloplasmin to chromosome region 8q21.13→q23.1 by in situ hybridization
Authors: Wang H. , Koschinsky M. , Hamerton J.L.
Published: May 2008

A processed gene for human ceruloplasmin has been localized to 8q21.13→q23.1 by in situ hybridization. This result confirms the assignment of this locus to chromosome 8 by Southern blot analysis using human × hamster somatic-cell hybrids and localizes the gene to the long arm of chromosome 8.
Mapping of probe p49f to the proximal part of the human Y chromosome long arm
Authors: Quack B. , Guérin P. , Ruffié J. , Lucotte G.
Published: May 2008

Probe 49f, subcloned from the Y chromosome locus DYS1 had previously been located to Yq. 11 by deletion mapping. Using in situ hybridization techniques we mapped the probe more precisely to subband Yq11.2.
Stock-specific differences in the number and chromosome positions of the nucleolar organizer regions in arctic char (Salvelinus alpinus)
Authors: Phillips R.B. , Pleyte K.A. , Hartley S.E.
Published: May 2008

Stock-specific variation in the number and chromosome locations of the nucleolar organizer regions (NORs) was found in North American and European stocks of arctic char (Salvelinus alpinus) using chromomycin A3 staining and silver staining. The number of NORs varied from two to eight per diploid genome. An unusual pattern of one NOR consistently present on both members of the largest submetacentric chromosome pair and additional NORs with variable locations was found. These findings suggest that NORs are being transposed to new chromosome sites in this species and this is discussed in relation to similar findings in other Salvelinus species and in amphibians.
Linkage relationships of the protein kinase C gamma gene which exclude it as a candidate for myotonic dystrophy
Authors: Johnson K.J. , Jones P.J. , Spurr N. , Nimmo E. , Davies J. , Creed H. , Weiss M. , Williamson R.
Published: May 2008

Using a cDNA probe for the gamma gene of protein kinase C (PKCG), an informative RFLP with a PIC value of 0.62 has been identified with the enzyme Mspl. The polymorphic bands have been assigned to chromosome 19. Analysis of the segregation of alleles for this probe in myotonic dystrophy families show several recombinants between PKCG and myotonic dystrophy (DM) and exclude this gene as a candidate for DM. Linkage relationships between PKCG and other loci on chromosome 19 are presented which exclude PKCG from the proximal region of chromosome 19 and which are consistent with the localization being at 19q13.2→qter.
Mapping of human lactate dehydrogenase-A, -B, and -C genes and their related sequences: the gene for LDHC is located with that for LDHA on chromosome 11
Authors: Li S.S.-L. , Luedemann M. , Sharief F.S. , Takano T. , Deaven L.L.
Published: May 2008

Human testis-specific lactate dehydrogenase-C (LDHC) gene-related sequences are located with the LDHA gene on chromosome 11. The LDHB gene is on chromosome 12. Chromosomes 1, 2, 4, 9, and 10 appear to contain LDHA gene-related sequences, whereas the X chromosome and chromosome 13 possess LDHB gene-related sequences.
Mapping of 12 translocation breakpoints in the Xp21 region with respect to the locus for Duchenne muscular dystrophy
Authors: Boyd Y. , Cockburn D. , Holt S. , Munro E. , Van Ommen G.J. , Gillard B. , Affara N. , Ferguson-Smith M. , Craig I.
Published: May 2008

Over 20 females have been reported to carry reciprocal X;autosome translocations with breakpoints in Xp21 and to suffer from Duchenne muscular dystrophy (DMD). We have positioned nine of these breakpoints with respect to the Duchenne gene by mapping probes from the DMD region against a panel of somatic cell hybrids, each containing one of the translocation chromosomes from a different female patient; further information as also been obtained by in situ hybridization, including the breakpoint location in a tenth DMD patient. We have also characterized two translocation breakpoints that lie in the same chromosomal region but which are not associated with the expression of DMD. All the DMD-associated translocation breakpoints examined lie at several sites within the DMD locus and between the two non-DMD breakpoints.
Immunocytogenetics: localization of transcriptionally active rRNA genes in nucleoli and nucleolus organizer regions by use of human autoantibodies to RNA polymerase I
Authors: Haaf T. , Reimer G. , Schmid M.
Published: May 2008

Cytological staining with silver nitrate (AgN03) has proved useful for the localization of nucleoli in interphase nuclei, as well as of nucleolus organizer regions (NORs) in metaphase chromosomes. The affinity of interphase nucleoli and chromosomal NORs to silver is a direct measure of the ongoing transcriptional activity of the rRNA genes or their activity during the preceding interphase, respectively. Correspondingly, human autoantibodies directed against chromatin-associated RNA polymerase I (RPI) should also be of value in the investigation of transcribed rRNA genes. Indirect immunofluorescence using the anti-RPI antibody as a probe has been employed successfully to visualize the chromosomal distribution of NORs in various mammalian species, as well as in human tumor cells. Immunofluorescence staining even permits the identification of heteromorphisms and small aberrations of the chromosomal NORs. The fluorescent intensity of interphase nucleoli is correlated with the different stages of nucleolar activation. In male gametogenesis, RPI-positive granules are present during meiotic prophase up to pachytene, as well as during the early and middle spermatid stages.
Synergistic effect of DAPI and thymidylate stress conditions on the induction of common fragile sites
Authors: Rocchi A. , Pelliccia F.
Published: May 2008

When supplied to human leukocytes grown in complete medium (RPMI 1640), DAPI, a nonintercalating compound specific for the AT bases of DNA, induces the appearance of three common fragile sites (CFRA) mapped at 1q42, 2q31, and 7p22. The same treatment with DAPI in a medium deficient in folic acid and thymidine (199 M) considerably increases the expression of these sites and induces the appearance of a further 16 CFRA sites at 1q24, 2p25, 4pl6, 4q25, 5pl5.3, 6p21.3, 6p25, 6q13, 9p24, 16pl3.3, 16q23, 17q21, 18q23, 20ql3.1, 21q21, and Xq28. The results point to the existence of a synergism between DAPI and thymidylate-stress culture conditions in inducing site-specific chromosome damage. The results also agree with the hypothesis that DAPI-induced CFRA sites are DNA late-replicating chromosomal areas rich in AT bases.
Synapsis of a chromosomal pair heterozygous for a pericentric inversion and the presence of a heterochromatic short arm
Authors: Hale D.W. , Greenbaum I.F.
Published: May 2008

Analysis of meiotic pairing configurations in a deer mouse heterozygous for both a pericentric inversion and the presence of a heterochromatic short arm at chromosome 15 revealed straight-paired synaptonemal complexes with equal axial lengths in a majority of the pachytene nuclei. Nonhomologous pairing in this bivalent occurs by direct heterosynapsis of the inverted segments followed by synaptic adjustment of the heterochromatin heteromorphism.
The polymorphic human α2-macroglobulin gene (A2M) is located in chromosome region 12p12.3→p13.3
Authors: Fukushima Y. , Bell G.I. , Shows T.B.
Published: May 2008

The gene for human α2-macroglobulin is assigned to the p12.3→p13.3 region of chromosome 12 by in situ hybridization.
Deletions in human chromosome arms 11p and 13q in primary hepatocellular carcinomas
Authors: Wang H.P. , Rogler C.E.
Published: May 2008

Normal liver and hepatocellular carcinoma (HCC) genotypes were compared at loci on most of the human chromosomes with probes that detect restriction fragment length polymorphisms. Six of fourteen tumors exhibited loss of heterozygosity of one or more markers on 11 p. Ten patients were informative for loci on 13q, and 5 of these 10 exhibited loss of heterozygosity for one or more of the 13q markers. Altogether, 9 of the 14 patients showed loss of a polymorphic allele for one or more loci on either 11p or 13q. A survey of loci on 16 additional chromosomes indicated that the deletions were not due to a general loss of heterozygosity in HCCs. Quantitative densitometry showed that each of the 10 deletions resulted in hemizygosity (no reduplication) of the remaining allele in tumor tissue. In contrast to hereditary embryonal tumors, in which reduplication of the remaining chromosome is the rule, simple deletion appears to be the primary mechanism responsible for the loss of heterozygosity in these adult, nonhereditary HCCs. These data show that HCCs arising in hepatitis B virus carriers are a genetically heterogeneous group of tumors, some of which may arise through 13q alterations, some through 11p alterations, some with both chromosomes altered, and some with both intact.
Synaptonemal complexes in a subfertile man with a pericentric inversion in chromosome 21
Authors: Gabriel-Robez O. , Ratomponirina C. , Croquette M. , Couturier J. , Rumpler Y.
Published: May 2008

Analysis of surface-spread synaptonemal complexes of zygotene and pachytene spermatocytes was carried out on a human male carrier of a pericentric inversion of chromosome 21 ascertained after four miscarriages. The synaptic behavior of the bivalent, which could be unambiguously identified by its nonaligned kinetochores, was analyzed. All zygotene and pachytene spermatocytes had 22 linearly paired autosomal bivalents, with apparently normal synaptonemal complexes, and no evidence of a loop configuration in the 50 cells analyzed. According to the XY type (classification of Solari), the cells were distributed across zygotene and pachytene stages, not exclusively in the late pachytene to which adjustment is conventionally thought to be confined. It is suggested that inverted segments heterosynapse at early pachytene, without previous homosynapsis. It is expected that this meiotic process leads to failure of crossing-over, reduces the production of unbalanced gametes, and the risk of recombinant offspring, but can increase the incidence of aneuploidy as a result of nondisjunction during meiosis I (a frequent cause of pregnancy wastage).
A functional mouse ornithine decarboxylase gene (Odc) maps to chromosome 12: further evidence of homoeology between mouse chromosome 12 and the short arm of human chromosome 2
Authors: Cox D.R. , Trouillot T. , Ashley P.L. , Brabant M. , Coffino P.
Published: May 2008

We have used a DNA probe specific for a functional mouse ornithine decarboxylase gene (Odc) in conjunction with a panel of Chinese hamster × mouse somatic cell hybrids to assign Odc to mouse chromosome 12. This assignment provides further evidence of genetic homoeology between a region of mouse chromosome 12 and the distal short arm of human chromosome 2.
Silver fox gene mapping: conserved chromosome regions in the order Carnivora
Authors: Rubtsov N. , Graphodatsky A. , Matveeva V.G. , Radjabli S.I. , Nesterova T.B. , Kulbakina N.A. , Zakian S.
Published: May 2008

Twenty-three silver fox × hamster somatic cell hybrid clones were used to assign 15 fox genes: GPI to chromosome 1; PGD to chromosome 2; MDH2 to chromosome 3; ESD to chromosome 6; LDHB to chromosome 8; NP to chromosome 10; LDHA to chromosome 11; APRT, ENOl, and PGM1 to chromosome 12; IDH1 and MDH1 to chromosome 16; and GLA, G6PD, and HPRT to the X chromosome. High-resolution G-banding of human, cat, mink, and fox chromosomes containing homologous regions (according to genetic maps) revealed regions of putative homology. The results lend support to the suggestion that the most considerable karyotypic reorganization of the ancestral genome in the order Carnivora occurred during Canidae formation. The details of karyotypic evolution in mammals are discussed.
Conserved repetitive DNA sequences (Bkm) in normal equine males and sex-reversed females detected by in situ hybridization
Authors: Kent M.G. , Elliston K.O. , Shroeder W. , Guise K.S. , Wachtel S.S.
Published: May 2008

In situ hybridization with a cloned banded krait sex-XY males and XY sex-reversed females. Lesser, but still signifi-specific repetitive DNA probe (Bkm) indicates a high concentracant, concentrations of Bkm sequences were mapped to horse tion of Bkm sequences on the horse Y chromosome in both normal chromosomes 3, 4, and 30.
Genetic mapping of the human polymeric immunoglobulin receptor gene to chromosome region 1q31→q41
Authors: Davidson M.K. , Le Beau M.M. , Eddy R.L. , Shows T.B. , DiPietro L.A. , Kingzette M. , Hanly W.C.
Published: May 2008

Polymeric immunoglobulin receptor (PIGR) is a transmembrane glycoprotein which is expressed by epithelial cells and is involved in the transcellular transport of polymeric immunoglobulins into secretions. We cloned the human gene for PIGR and used the clone to obtain probes to determine the chromosomal localization of PIGR. Analysis of somatic cell hybrids and in situ chromosomal hybridization localized the human PIGR gene locus to 1q31→q41.
BrdU replication patterns demonstrating chromosome homoeologies in two fish species, genus Eigenmannia
Authors: Almeida Toledo L.F. , Viegas-Péquignot E. , Foresti F. , Toledo Filho S.A. , Dutrillaux B.
Published: May 2008

The karyotypes of two fish species (genus Eigenmannia) from Brazilian rivers were studied with various chromosome banding techniques. BrdU incorporation appears to be the most powerful method for identifying chromosome homoeologies between karyotypes. It also demonstrates asymmetrical heterochromatic segments, suggesting an uneven distribution of A-T base pairs in the two DNA strands. In one of these species, males differ from females by the acquisition of a Robertsonian translocation, resulting in a loss of a heterochromatic segment, which may be related to sex differentiation.
Use of an alphoid satellite sequence to locate the X chromosome automatically, with particular reference to identification of the fragile X
Authors: Fantes J. , Gosden J. , Piper J.
Published: May 2008

An alphoid DNA sequence primarily located on the X chromosome was labeled with biotin and hybridized in situ to preparations of metaphase chromosomes derived from fragile X-affected individuals; hybridization sites were detected immunologically. Labeled X chromosomes were located automatically in digitized images of metaphase cells by searching for the concurrence of a pronounced peak in the longitudinal density profile with the centromere in medium-sized chromosomes having a suitable centromeric index. Approximately 70% of the X chromosomes were detected by a simple classifier; this rate is similar to the automatic classification rate obtained with G-banded metaphases. The frequency of detection of the fragile X site obtained when scored directly from the microscope using this new preparation technique did not differ significantly from the frequency obtained in the same sample by means of a conventional technique. The frequency obtained by visual scoring of digitized images was slightly higher, but not significantly so.
Chromosomal assignments of human type I and type II cytokeratin genes to different chromosomes
Authors: Romano V. , Bosco P. , Rocchi M. , Costa G. , Leube R.E. , Franke W.W. , Romeo G.
Published: May 2008

The chromosomal location of representative members of the type I and type II subfamilies of the cytokeratin multigene family was determined using specific cDNA probes in Southern blot hybridization with DNA from somatic cell hybrids. Our results show that the gene encoding human type II cytokeratin 4 resides on chromosome 12 and that encoding type I cytokeratin 15 is located on chromosome 17. The results indicate that cytokeratins are not concentrated in only one cluster. The possibility of the existence of separate type I and type II cytokeratin gene clusters is discussed.
VNTR (variable number of tandem repeats) markers show loss of chromosome 17p sequences in human colorectal carcinomas
Authors: Lothe R.A. , Nakamura Y. , Woodward S. , Gedde-Dahl, Jr. T. , White R.
Published: May 2008

Restriction fragment length polymorphisms at 53 autosomal loci were screened for heterozygosity in 40 colorectal cancer patients. The DNA pattern in constitutional versus tumor/ polyp tissue was compared. More than half of the markers tested were of the VNTR (variable number of tandem repeats) type, giving the patient panel a higher informational content, since the frequency of individuals heterozygous for a particular marker is increased. Loss of alleles was revealed in 40% of the tumors from constitutionally heterozygous patients at the chromosome 17p loci, identified by the markers YNH37 and YNZ22. Similar losses were also detected on other autosomes, but at a significantly lower frequency. Our results suggest that hemi/homozygosity of 17p alleles plays a role in the development of a major subset of colorectal carcinomas. Similar observations regarding other autosomal loci may be interpreted as random losses in these tumors, or they may indicate loci important to minor clinical subclasses of colon carcinomas.
Chromosome assignment of the gene loci ETS1 and THY1 in the owl monkey
Authors: Ma N.S.F. , Gerard D.S.
Published: May 2008

Our previous assignment of the gene loci HBB, HRASl, INS, PTH, LDHA, and CAT to owl monkey chromosome 19 of karyotype VI (K-VI) indicated a putative homology of this owl monkey chromosome with the short arm of human chromosome 11 (HSA 11p). To investigate further the extent of shared homolgy, we localized in the owl monkey complement two genes known to be on HSA 11q. Segregation analysis of ETS1 and THY1 homologous DNA in three karyotypically different panels of rodent × owl monkey somatic cell hybrids provided evidence for the syntenic assignment of these loci to homologous chromosomes of three owl monkey karyotypes, namely, chromosomes 4 (K-VI), 3 (K-II), and 5 (K-V). The results indicate a disruption of syntenic gene loci on the distal portion of HSA 11q from 11p during primate evolution.
Synaptonemal complex analysis of B-chromosome behavior in meiotic prophase I in the East-Asiatic mouse Apodemus peninsulae (Muridae, Rodentia)
Authors: Kolomiets O.L. , Borbiev T.E. , Safronova L.D. , Borisov Y.M. , Bogdanov Y.F.
Published: May 2008

The mitotic and meiotic chromosomes of four male East-Asiatic mice, Apodemus peninsulae, having three to seven chromosomes in addition to the standard karyotype (2n = 48), were investigated. B-chromosomes were represented by medium-sized metacentric and dotlike chromosomes. Mosaicism of bone marrow cells due to a numerical variation of accessory chromosomes was established for the males examined. Capacity of B-chromosomes to- form axial elements and synaptonemal cornplexes in meiotic prophase I was revealed by electron microscopy. The occurrence of univalents of different morphology, bivalents, and multivalents, corresponding to B-chromosomes, was demonstrated. An increase in the number of B-chromosomes was found in spermatocytes at zygotene-pachytene relative to the number in bone marrow cells, which may be evidence of B-chromosome accumulation in the germ cell line of the East-Asiatic mouse.
A new application of in situ hybridization: detection of numerical and structural chromosome aberrations with a combination centromeric-telomeric DNA probe
Authors: van Dekken H. , Bauman J.G.J.
Published: May 2008

Fluorescent in situ hybridization provides a fast method for detection of specific nucleic acid sequences. We have used high-resolution, single-color fluorescent in situ hybridization with a combination centromeric-telomeric DNA probe, specific for chromosome 1, to investigate the feasibility of simultaneous assessment of numerical and structural chromosome aberrations. The K562 leukemia cell line served as a model.
Localization of the gene for acetyl-CoA carboxylase to human chromosome 17
Authors: Milatovich A. , Plattner R. , Heerema NA. , Palmer CG. , Lopez-Casillas F. , Kim K-H.
Published: May 2008

In situ hybridization was used to localize a cDNA probe of the acetyl-CoA carboxylase gene to human metaphase chromosomes. A significant proportion of the grains were situated over chromosome band 17q21. In situ hybridization to a t(6; 17)(p25;q21.33) confirmed the location of the gene proximal to 17q21.33.
Segregation and transmission of chromosomes from a reciprocal translocation in Gallus domesticus cockerels
Authors: Bonaminio G.A. , Fechheimer N.S.
Published: May 2008

Segregation behavior of a reciprocal translocation involving the long arm of chromosome No. 1 and a microchromosome was studied in secondary spermatocytes and embryos produced by heterozygous cockerels. The types and frequencies of the various balanced and unbalanced chromosome complements were determined. Complementary products of segregation did not occur in the expected ratios of 1:1 in secondary spermatocytes. The excess of spermatocytes with deficiency of the long arm and duplication of the short arm might be the result of lagging of the long arm at meiosis I, the centromere of the long arm being derived from a microchromosome. In the samples of secondary spermatocytes and embryos 52.5% and 49.6%, respectively, contained balanced chromosome complements. A significantly higher proportion of duplications and deletions of the long arm was seen in embryos than in secondary spermatocytes. Conversely, a lower proportion of duplications and deletions of the short arm was seen in embryos than in secondary spermatocytes. Apparently, spermatogenic cells bearing different unbalanced genomic contents are not equally viable or fertile.
Specific sites for EBV association in the Namalwa Burkitt lymphoma cell line and in a lymphoblastoid line transformed in vitro with EBV
Authors: Caporossi D. , Vernole P. , Porfirio B. , Tedeschi B. , Frezza D. , Nicoletti B. , Calef E.
Published: May 2008

Localization of Epstein-Barr virus (EBV) DNA was studied by in situ hybridization on chromosomes from the Namalwa Burkitt lymphoma cell line and from a lymphoblastoid cell line transformed in vitro (ATL9/g). The five chromosome bands 1p32, 1q31, 5q21, 13q21, and 16p13 showed the presence of EBV DNA in both of the lines. Grain deposition at the site on chromosome 1 q of the Burkitt line was particularly intense. It was also found that EBV DNA in the lymphoblastoid cell line co-localized with a stable achromatic gap at 1p32 whose presence seems to confer a proliferative advantage on the cells.
Chromosomal rearrangements in rock wallabies, Petrogale (Marsupialia, Macropodidae)
Authors: Eldridge M.D.B. , Dollin A.E. , Johnston P.G. , Close R.L. , Murray J.D.
Published: May 2008

Chromosomal rearrangements in three karyotypi-cally distinct, but morphologically and biochemically similar, races of rock wallabies (Petrogale) from North Queensland, Australia, were examined by C- and G-banding of cultured fibroblasts and by analysis of synaptonemal complexes from gonads of hybrid individuals. The assimilis race (2n = 20) had a submetacentric 6; 10 centric fusion, whereas the Mt.Claro(2n = 20) and Mareeba (2n = 18) races shared an identical submetacentric 5; 10 centric fusion. The 5 of this 5; 10 fusion was inverted in both races with respect to the free 5 of the assimilis race. Moreover, the Mareeba race had a unique acrocentric 6;9 fusion. Thus, while all three races are closely related, it is apparent from the chromosomal orientation that the Mareeba and Mt. Claro races are more closely related to each other than either is to the assimilis race.
Sexual immaturity and maternal age: incidence of aneuploidy and polyploidy in first-cleavage mouse embryos
Authors: Catala V. , Estop A.M. , Santalo J. , Egozcue J.
Published: May 2008

The influence of maternal age on the incidence of aneuploidy and polyploidy was studied, using C57B1/6J × CBA/ Ca hybrid mice, including immature females, as gamete donors. The age of the females ranged from 3.5–4 wk (immature or prepubertal), to 10–12 wk (young adults), to 24–28 wk (aged females). Ovulation was induced with gonadotrophins, and the differential condensation of paternal and maternal chromosomes was used to elucidate the origin of chromosome abnormalities in first-division metaphase plates. The results indicated a high incidence of aneuploid oocytes in immature and older female mice, as compared to young adult females. Eggs of immature female mice underwent polyspermic fertilization more often than those of young adults and older females, and the production of diploid oocytes was more frequent in immature females than in the other age groups.
Regional localization of the fibronectin and gamma crystallin genes to mouse chromosome 1 by in situ hybridization
Authors: Zneimer S.M. , Womack J.E.
Published: May 2008

Genes for fibronectin, gamma crystallin, and isocit-rate dehydrogenase-1 are syntenic in mouse, man, and cow. In an effort to physically locate this conserved chromosome region in the genomes of the respective species, we have localized the fibronectin and gamma crystallin genes to mouse chromosome 1 region C1–5 by in situ hybridization. In situ hybridization was conducted on metaphase chromosomes of bone marrow preparations of Rb 1.7 mice. These cells contain Robertsonian translocated chromosomes 1 and 7 as the only submetacentric chromosome in an otherwise acrocentric genome. Physically mapping these genes to mouse chromosome 1 now enables comparisons of the genetic map and the physical map on the proximal half of this chromosome. Genes in this conserved region of mouse chromosome 1 are also involved in resistance to intracellular pathogens, and the chromosomal localization of this region may facilitate the identification of homoeologous genes in other species.
Confirmation of avian sex-chromosome linkage of liver cytosolic aconitase (ACO1)
Authors: Lacson J.M. , Morizot D.C.
Published: May 2008

Frequencies of liver cytosolic aconitase (ACO1) allozyme phenotypes in female zebra finches (Poephilaguttata) conformed to a sex-chromosome-linked model of inheritance. Since birds are characterized by female heterogamety (ZZ males, ZW females), the observed absence of female heterozygotes for the cytosolic aconitase gene is interpreted as suggesting linkage of the ACO1 locus to the Z chromosome and hemizygous expression of this locus. Confirmation of this linkage assignment provides further support for the concept of evolutionary conservation of the avian Z chromosome.
Congenital chromosome breakage clusters within Giemsa-light bands and identifies sites of chromatin instability
Authors: Koduru P. , Chaganti R.
Published: May 2008

Analysis of the distribution of published chromosome breaks in cells with constitutional chromosome aberrations showed a nonrandom distribution of breaks among chromosomes and chromosome regions. A significant amount of breakage occurred at Giemsa-negative bands. In addition, chromosome sites associated with a number of fragile sites and cellular oncogene
Fragile sites, telomeric DNA sequences, B chromosomes, and DNA content in raccoon dogs, Nyctereutes procyonoides, with comparative notes on foxes, coyote, wolf, and raccoon
Authors: Wurster-Hill D.H. , Ward O.G. , Davis B.H. , Park J.P. , Moyzis R.K. , Meyne J.
Published: May 2008

Earlier studies of the genus Nyctereutes disclosed two subspecies of differing chromosome numbers accompanied by B chromosomes. To further define the relationship of these subspecies to each other, and to other carnivores, and to learn more about the structure and function of their chromosomes, we charcterized and compared the genomes in terms of DNA content by flow cytometry, fragile sites induced by aphidicolin, and telomere sequences using biotinylated DNA probes detected with fluorescence. We also characterized the B chromosomes of these two subspecies.
Gene sequences coding for S-adenosylmethionine decarboxylase are present on human chromosome 6 and the X and are not amplified in colon neoplasia
Authors: Radford D.M. , Eddy R. , Haley L. , Henry W.M. , Pegg A.E. , Pajunen A. , Shows T.B.
Published: May 2008

Sequences for human S-adenosylmethionine decarboxylase, an enzyme involved in polyamine biosynthesis, which is evated in tumors, have been localized on chromosome 6 and the X.