摘要:

Conventional observations of mitotic chromosomes from two male blue foxes, revealing a centric-fusion translocation and whole-arm heterochromatin, were verified by synaptonemal complex analysis. This analysis revealed that the centric fusion had been preceded by a conspicuous loss of chromosome material in the two one-armed chromosomes involved, but the chromosomal origin of the centric-fusion kinetochore could not be established. The nontranslocated chromosomes of the trivalent, which in all cells but one were in cis configuration, had reached by early pachytene a stage in which almost complete homologous pairing and nonhomologous association or pairing of the free ends of the chromosomes could be observed. In later stages, complete pairing of the nontranslocated chromosomes with the corresponding arms of the centric-fusion translocation was seen occasionally. One to six autosomal bivalents demonstrated unpaired heterochromatic arms in early pachytene, and the heterochromatic chromosome arms were sometimes unpaired even in late pachytene. Some of them showed a distinct size heteromorphism in late zygotene and early pachytene. In most late-pachytene cells, however, the heteromorphic chromosomes were completely length-adjusted. Only a small fraction of the cells showed pairing interference between nonhomologous chromosomes.

ISSN:1424-8581    

DOI:10.1159/000133101

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

We have previously reported the identification and basic characterization of two biallelic TaqI RFLPs, A and B, of the 3’ end of the human ACPP locus in an unselected Finnish population (Winqvist et al., 1989). In the present investigation, a similar allelic distribution was observed in patients with prostatic cancer or benign hyperplasia. In addition, it was found that the DNA sequences generating RFLP-B are located further downstream from the RFLP-A sequence

ISSN:1424-8581    

DOI:10.1159/000133102

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A t(X;15)(q23;q25) was detected during cytogenetic investigation of a lymphoblastoid cell line established from a female patient with Fanconi anemia. The translocation was apparently balanced at passage 300 and unbalanced at passage 13. A chromatid exchange between both the normal and the der(15), between the centromere and band 15q25, may explain these results. Replication studies, following BrdU incorporation, indicate that the segment Xq23→qter from the der(15) is early replicating whereas segment Xpter→q23 from the der(X) is late replicating. Since the normal X was early replicating, it is concluded that the segment of the long arm of chromosome X, separated from its inactivation center by the translocation, was reactivated. This interpretation is conñrmed by the methylation patterns of the hypoxanthine phosphoribosyltransferase gene (HPRT), mapped on Xq26, which corresponds to that of an active gene, whereas that of phosphoglycerate kinase (PGK1), which remained on the der(X), corresponds to that of an inactive gene. This is the first example of reactivation of a segment of the X chromosome following a structural rearrangement in somatic c

ISSN:1424-8581    

DOI:10.1159/000133103

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Fluorescence in situ hybridization (FISH) is being used increasingly in clinical practice; however, current FISH techniques require fresh material, and there is considerable variation in hybridization efficiency between laboratories. We have modified a FISH technique described by Pinkel et al. (1986) that works not only on freshly G-banded material but also on cytogenetic preparations ranging in age from 2 wk to 12yr. We have tested this technique on several centromeric alphoid satellite probes (D1Z5, D7Z1, D17Z1, DXZ1, and DYZ3) and one noncentromeric minisatellite probe (D1Z2). Our average hybridization efficiency on freshly banded preparations for these probes is consistently greater than 90 %. The combination of higher efficiency and the ability to perform hybridization on previously G-banded material makes this a valuable technique for retrospective analyses.

ISSN:1424-8581    

DOI:10.1159/000133104

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The human genome carries multiple copies of sequences related to endogenous retroviral genomes that include long terminal repeat (LTR) sequences. We used the LTR of one such viral genome, called HERV-A, as a probe in Southern analysis to examine the distribution profiles of the hybridizing DNA in the genomes of twelve human × rodent hybrid cell lines carrying one or a few human chromosomes, and in the DNA samples prepared from six sorted, individual chromosomes. The HERV-A sequence was found to be widely distributed among different chromosomes and the Southern patterns for chromosomes 5, the X, and the Y, each obtained in duplicate from independently prepared cell lines or sorted chromosomes, were matched. Chromosome-specific Southern profiles can be used to monitor chromosomes in hybrid cells or to characterize chromosome aberrations, such as deletions

ISSN:1424-8581    

DOI:10.1159/000133105

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The mapping and sequencing of two clones that surround the centromere of chromosome 21 are presented. These clones specify the most proximal known low-order repeat n 21p (p21–7D) and the most proximal known single-copy sequence on 21q (pUT-B37 at locus D21S120

ISSN:1424-8581    

DOI:10.1159/000133106

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The human 5S rRNA genes have been localized by in situ hybridization to metaphase chromosomes. Tritiated RNA probes were made by transcription from 2,300-bp and 638-bp DNA fragments containing an isolated human 5S rRNA gene. Hybridization to metaphase spreads from a balanced reciprocal translocation carrier, 46, XX, t(1;7)(q42.13;p11.1), showed that the 5S rRNA genes were entirely localized on the normal and the derivative chromosome 1. This narrows the chromosome position of the major fraction of 5S rRNA genes and pseudogenes to the region 1q42.11→q42.1

ISSN:1424-8581    

DOI:10.1159/000133107

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Chromosome mapping of the human gene encoding the 230-kDal autoantigen of an autoimmune skin disease, bullous pemphigoid, was performed using flow-sorted human chromosomes of cells of normal karyotype and cells carrying a reciprocal translocation t(6;16)(q15;q24). The cDNA of the autoantigen hybridized with intact chromosome 6 and translocation chromosome 6p– (6pter→q15::16q24→qter). The gene (BPA230) was located to the chromosome region 6pte

ISSN:1424-8581    

DOI:10.1159/000133108

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

We have localized the genes which encode the human type II epidermal keratins K5, K6a, and K6b and the simple epithelial keratin K7 (KRT5, KRT6A, KRT6B, and KRT7, respectively) to chromosome 12 using Southern blot analysis of somatic cell hybrids. In addition, we have sublocalized the genes for K6a and K7 to bands 12q12→q14 on the long arm of this chromosome by in situ hybridization of metaphase chromosome

ISSN:1424-8581    

DOI:10.1159/000133109

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Growth hormone-releasing factor (GHRF), a hypothalamic releasing factor also named somatocrinin, influences the secretion and synthesis of growth hormone. Human GHRF is encoded by a single gene which was assigned to chromosome 20 by dot-blot analysis of DNA from dual laser sorted chromosomes. Using a radioactive cDNA probe, we localized the GHRF gene to chromosome 20p12 or near band 20p12.

ISSN:1424-8581    

DOI:10.1159/000133110

出版商:S. Karger AG    

年代:1991

数据来源: Karger