ISSN:1424-8581    

DOI:10.1159/000133654

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Using a panel of somatic cell hybrids we have mapped the locus for Rap1-GTPase activating protein 1 (RAP1GA1) to human chromosome 1. Fluorescence in situ hybridization experiments independently confirmed the chromosomal localization and refined it to 1p36.1→p3

ISSN:1424-8581    

DOI:10.1159/000133655

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We previously reported a subject with 46, XX true hermaphroditism who had a 46, X, del(X) karyotype and Y-chromosomal sequences in genomic DNA. We hypothesized that the Y-chromosomal sequences were translocated to the deleted X chromosome and that the incomplete testis determination of this individual was the result of inactivation of the translocated X chromosome. In situ hybridization studies demonstrated that the Y-chromosomal sequences were located on the distal portion of the short arm of the deleted X chromosome. Investigation of the replication of the X chromosome, using a modified R-banding technique and localization of Y-chromosomal sequences by in situ hybridization, showed that the translocated X chromosome was late replicating in all 100 EBV-transformed lymphoblasts that were examined. By contrast, when cells from a subject with 46, XX maleness were studied, the translocated X chromosome was late replicating in only 21 of 47 cells. As the late-replicating X chromosome is presumed to be the inactive X chromosome, selection of cells in which the Y-bearing X chromosome has been inactivated may play a role in the incomplete testis determination in subjects with “Y-positive” 46, XX true hermaphrodit

ISSN:1424-8581    

DOI:10.1159/000133656

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We have molecularly cloned portions of equine satellite-type DNA and investigated the organization of the DNA sequence of the cloned segments. Sequence analysis and dot-blot analysis, using the cloned sequence (ES200) as a probe, indicate that the satellite-type DNA sequence consists mainly of 221-bp tandem repeats and represents 3.7–11% of the equine genome. Southern blot analysis further shows that (1) no sequences homologous to ES200 exist in the human, swine, and bovine genomes and that (2) the fragment pattern of the satellite-type DNA produced by Apal cleavage shows a slight difference among equine DNA samples, indicating a slight sequence variation between individual horses. To localize the satellite-type DNA in the horse genome, chromosome spreads on glass slides were first subjected to G-banding to identify each chromosome and then hybridized in situ with biotin-labeled ES200. The chromosome banding, together with the hybridization, demonstrates that the satellite sequences are preferentially localized on the centromeric regions of all chromosomes except chromosomes 2, 9, and 1

ISSN:1424-8581    

DOI:10.1159/000133657

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The phenomenon of spontaneous differentiation (without bromodeoxyuridine in the culture medium) of sister chromatids of mouse chromosomes at the blastocyst stage of embryogenesis is described. The frequency of sister chromatid exchanges in such differentiated chromosomes was calculated.

ISSN:1424-8581    

DOI:10.1159/000133658

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We have used a panel of human × rodent somatic cell hybrids containing translocations involving chromosome 14 to regionally localize 17 genes and 5 random segments previously mapped to chromosome 14. Each hybrid cell line contains a specific fragment of chromosome 14, with breakpoints at 14q11.2, 14q21, 14q22, 14q24.3 or in two different regions of 14q32.1. The enzyme deficient in glycogen storage disease type VI, liver glycogen phosphorylase (PYGL), has been localized by in situ hybridization to 14q21→q22, near the q21→q22 band interface. Four additional genes, chromogranin A (CHGA), myosin (MYH7), tRNA proline 2 (TRP2) and c-FOS (FOS) and four random segments, D14S26, D14S12, D14S14 and D14S13 have been more precisely localized. This study also defines a hybrid cell panel with seven mapping intervals, that will be useful for further physical mapping of new

ISSN:1424-8581    

DOI:10.1159/000133659

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Using fluorescence in situ hybridization, the human α-fodrin gene (nonerythroid α spectrin, SPTAN1), a member of the spectrin gene superfamily, was mapped to 9q33→q34. This locus is near the translocation breakpoint region in the Philadelphia (Ph1) chromosome, t(9;22)(q34;q11). In a human chronic myelogenous leukemia cell line with the Ph1 chromosome, K562, the α-fodrin gene mapped centromeric to the translocation breakpoint, indicating that the α-fodrin gene is not translocated to the Ph1 chromosome in this cell

ISSN:1424-8581    

DOI:10.1159/000133660

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

In constructing complete human chromosome maps, the relative order of markers and their precise chromosomal location will be combined. Multicolour in situ hybridisation, in which two probes are simultaneously hybridised to chromosomes and subsequently distinguished, potentially will provide both types of information. Using this technique, we have produced an ordered map of eight human chromosome 3 DNA markers, using small, single-copy probes that can detect target sequences ranging in size from 4 kb to as little as 500 bp.

ISSN:1424-8581    

DOI:10.1159/000133661

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Genetic sequences of the novel NSP gene, which encodes neuroendocrine-specific proteins, were isolated from cDNA libraries constructed with mRNA isolated from human lung carcinoma cells. Hybridization analysis of a panel of human × mouse cell hybrids with an 0.8-kb NSP cDNA probe indicated that the human NSP gene is probably located on chromosome 14. Fluorescence in situ hybridization analysis of metaphase chromosomes using overlapping genomic clones of NSP as a probe localized the NSP gene to chromosome region 14q21→q

ISSN:1424-8581    

DOI:10.1159/000133662

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The segregation products in zygotes of females heterozygous for the mouse Rb(6.16) translocation were studied. Of 191 first-cleavage metaphase zygotes recovered from 16 females mated to chromosomally normal males, 132 were cytogenetically analyzed after sequential G- and C-banding. There were no products of adjacent segregation, since the six chromosomal imbalances were unrelated to the translocation. Alternate segregation was seen in 126 (95.5%) of the zygotes, with 85 being chromosomally normal and 41 carrying the translocation. These results indicate preferential alternate segregation and a significant deviation from the Mendelian 1:1 ratio (P < 0.005) for reciprocal alternate segregants, as seen earlier for males with this translocation. However, the approximately 2:1 ratio for normal-to-balanced segregants in females is lower than the ratios consistently seen for males. This supports the notion that there are different underlying causes of the distortion in the sexes.

ISSN:1424-8581    

DOI:10.1159/000133663

出版商:S. Karger AG    

年代:1994

数据来源: Karger