ISSN:1424-8581    

DOI:10.1159/000134653

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000134654

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000134655

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

The effect of DNA ligase from T4 phage on the modulation of the damage induced by bleomycin was studied. CH06 cells were electroporated with either bleomycin alone or bleomycin plus T4 DNA ligase, and both cytogenetic and clonogenic assays were carried out in parallel. Our results show that T4 DNA ligase is able to decrease the frequency of chromosome aberrations in bleomycin-treated cells while increasing cell survival.

ISSN:1424-8581    

DOI:10.1159/000134656

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

The meiotic segregation patterns of 2 reciprocal translocations t(7;9)(q33;p21) and t(7;18)(q35;q11) were analyzed in sperm of 2 heterozygote carriers. Both sperm karyotyping and in situ PRINS labeling of sperm nuclei were performed on a sperm sample from each subject. Using the humster technique, 54 and 72 sperm chromosome complements were successfully analyzed for the t(7;9) and the t(7;18) respectively. The frequencies of alternate, adjacent 1, adjacent 2 and 3:1 segregations were 44.44%, 37.04%, 12.96% and 5.56% for the t(7;9) and 33.33%, 43.05%, 19.45% and 4.17% for the t(7;18). The PRINS procedure allowed the rapid screening of large samples of spermatozoa. However, alternate and adjacent 1 segregants were not discriminated because of the generation of centromeric signals. The segregation pattern was determined on 10,658 spermatozoa for the t(7;9) and 10,462 for the t(7;18). The distributions of segregants were similar to those obtained by sperm karyotyping. These data were pooled with results from 37 reciprocal translocations previously studied by sperm karyotyping and 6 recently investigated by FISH. The analysis of these compiled data demonstrates the particularity of the production of imbalances in male gametes; independent of the predisposition for a type of imbalance at term, there is a preferential production of adjacent 1 imbalance in sperm.

ISSN:1424-8581    

DOI:10.1159/000134657

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

The murine cytokine inducible SH2-containing (Cis) protein gene (Cish) was recently cloned and shown to have a growth inhibitory function. We have isolated cDNAs coding for its human homologue (CISH) and assigned the gene to 3p21.3 by fluorescence in situ hybridization. Northern blot analysis showed CISH expression in various epithelial tissues including lung and kidney, in which tumors frequently exhibit 3p21.3 deletions.

ISSN:1424-8581    

DOI:10.1159/000134658

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

Exon trapping was used to identify portions of genes on human chromosome 21. BLAST search of databases revealed that the trapped sequence hmc02a08 (one of 559 different trapped exons) was identical to a region of GenBank entry U61166 for an SH3 (Src-homology) domain-containing gene SH3D1A (formerly called SH3P17; Sparks et al., 1996). We subsequently mapped this gene to YACs and cosmids within 21q22.1→q22.2 between DNA markers D21S319 and D21S65 using hybridization and PCR amplificatio

ISSN:1424-8581    

DOI:10.1159/000134659

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

Conventional G- and C-banding were used to describe the chromosomes of the whistling rat, Parotomys brantsii. This species has a diploid number of 42 chromosomes. C-banding showed that large blocks of pericentromeric hete-rochromatin or entirely heterochromatic short arms characterize most chromosomes. G-banding and fluorescence in situ hybridization (FISH) incorporating two laboratory mouse chromosome paints were used to compare the genomes of P. brantsii, the bush karoo rat (Otomys unisulcatus; 2n = 28), and the vlei rat (O. irroratus; 2n = 28–31). The FISH results showed that sequences corresponding to mouse chromosome 2 are conserved as a single chromosome in O. irroratus but are found on two separate chromosomes in P. brantsii and O. unisulcatus. In contrast, a mouse chromosome 6 paint showed hybridization to single chromosomes in all three species examined. When taken together, the FISH and cytogenetic results produce two important findings: (1) previously undetected homoeologies between the two Otomys species can be identified and (2) a high proportion of conserved chromosomes exists between P. brantsii and O. unisulcatus. This, in conjunction with previously reported allozyme and immunoblot data, raises serious questions about the validity of the current generic taxonomy of the Otomyina

ISSN:1424-8581    

DOI:10.1159/000134660

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

We examined the stability of different types of DNA microsatellite markers in γ-radiation-induced thymic lymphomas as well as normal, nontumorous tissues of F1 hybrid mice derived from the parental strains C57BL/6J, RF/J, and BALB/cJ. Surprisingly, the D4Mit12 microsatellite showed genomic instability in a significant fraction of DNAs of the (C57BL/6J × BALB/cJ) F1 hybrids with independence of the tumor phenotype. This instability was not found in the reciprocal F1 DNAs, in DNAs of the parental strains, or in DNAs of (C57BL/6J × RF/J) F1 hybrid mice. These results suggest that the instability of the D4Mitl2 microsatellite is dependent on its repeat length, the genetic background of F1 hybrids, and the maternal origin of the C57BL/6J alle

ISSN:1424-8581    

DOI:10.1159/000134661

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

The neotropical rodents Akodon cursor (2n = 14, 15, and 16) and A. montensis (2n = 24 and 25), two closely related and morphologically indistinguishable species, have been compared by G-banding and chromosome painting. In situ hybridization of a biotinylated DOP-PCR product obtained from a microdissected chromosome of A. cursor onto A. montensis chromosomes was performed in combination with localization of telomeric sequences using a (TTAGGG)n oligomer as a FISH probe. The results provide evidence of the complex chromosomal rearrangements suggested by GTG-banding analysis, indicating the origin of one A. cursor autosome from three different A. montensis autosomes. Furthermore, the complete cytogenetic homeology between the A. cursor and A. montensis karyotypes was determined, along with the occurrence of tandem fusions and pericentric inversions and the loss of telomeres, centromeres, and chromosome arms. Evidence for the ancestral origin of the A. cursor karyotype is also provided.

ISSN:1424-8581    

DOI:10.1159/000134662

出版商:S. Karger AG    

年代:1997

数据来源: Karger