摘要:

A de novo 11p+ chromosome was found in a child with mild mental retardation but no other remarkable dysmorphic characteristics. Banding studies suggested a duplication of regions 11p13 and 11p14 or regions 11p14 and 11p15. Using fluorescent in situ hybridization and digital imaging microscopy, we mapped probe p32.1 (D11S16) to the proximal part of region lip 14 (lip 14.1) and demonstrated duplication of this probe in our patient. Southern hybridization showed duplication of p32.1 and other probes located at 11pl 3 and 11ρl4, but the gene for α calcitonin (CALCA), located at 11p15, was not duplicated. The application of these techniques led to the identification of the duplication as dir dup(11 )(pter→p 13::p 15.1→

ISSN:1424-8581    

DOI:10.1159/000133068

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

An alphoid repetitive DNA (D8Z2) probe specific for the pericentromeric region of chromosome 8 was used to detect extra copies of chromosome 8 in bone marrow cells obtained from 10 patients with hematological disorders and five controls. Numerical aberrations of chromosome 8 were established by conventional banding techniques. Trisomy 8 was found in four patients with myelodysplastic syndrome (MDS) and three with acute myeloid leukemia (AML). Three additional patients with MDS exhibited an extra chromosome 8 in only one metaphase. In five of the seven trisomy cases, the presence of the trisomy 8 clone was confirmed by in situ hybridization (ISH). In one case of AML with trisomy 8, detected by GTG-banding, no significant numbers of cells containing three spots were found using the alphoid repetitive probe; however, hybridization with a chromosome 8-specific library revealed that the alleged extra chromosome 8 was a translocation chromosome containing only the long arm of chromosome 8. Due to a lack of material, it was not possible to achieve optimal ISH results on the trisomy 8 bone marrow cells of patient 7. In the three MDS patients with a single trisomy 8 metaphase, a slight, albeit significant, increase of trisomy 8 interphase cells was found with ISH. We conclude that this probe is useful for cytogenetic studies. Moreover, ISH, in general, is a powerful tool for precise classification of chromosomal aberrations and can also contribute significantly to the clinical evaluation of patients with hematological disorders.

ISSN:1424-8581    

DOI:10.1159/000133069

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A new radiation-induced mutation in the mouse, tabby-25H (Ta25H), has proved to be a deletion which spans both the tabby and testicular feminization (Tfm) loci on the X chromosome. The Ta phenotype closely resembles that of the original TaFamutation in both the heterozygous and hemizygous conditions but Ta25H/Y animals additionally show the Tfm/Y phenotype, being externally female but possessing abdominally located testes. There is a shortage of both Ta25Hl+ and Ta25H/Y classes relative to their normal sibs among the progeny of Ta25H/+ females at weaning age and this was indicated to be due to prenatal or neonatal losses. Exencephaly was observed in some members of both classes prior to birth. Both Ta25Hclasses tend to be runted at weaning but, remarkably, Ta25H/+ females often show a range of abnormalities not evident in Ta25HIY animals. When probes for the Zfx, Ccg-1, Phk, and DXPas19 loci, which lie close to Ta, were hybridised to DNAs from Ta25Hhemizygotes, the profiles of the X-linked bands were similar to those of control DNAs, suggesting these loci lie outside the deletion. However, a clear absence of an X-linked band was found with human androgen receptor probes, indicating that the Tfm locus is indeed missing. The deletion, therefore, extends a minimum of 1.5 cM and, with its proximal and distal boundaries partially defined, it could be as large as 4 cM. As Ta25H/+ females show the striped X-inactivation coat pattern, the putative X-inactivation centre, Xce, which lies close to Ta, cannot be located within the region deleted. The greasy (Gs) locus similarly appears to lie outside the deletion.

ISSN:1424-8581    

DOI:10.1159/000133070

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A 340-bp EcoRl fragment of α satellite DNA from human chromosome 12 has been isolated and used in molecular cytogenetic and genetic studies. The clone, pSP12-1, detects tandemly repeated 1.4-kb repeat units at the centromeric region of chromosome 12. By fluorescence in situ hybridization, bio-tinylated pSP12-1 is highly specific for chromosome 12 and has been used to confirm an i(12p) in a case of Pallister-Killian syndrome, both in metaphase spreads and in interphase nuclei. A dominant DNA polymorphism for the centromeric D12Z3 locus is detected with the enzyme Taql. In addition, a high frequency of D12Z3 array length polymorphisms can be detected using pulsed-field gel electrophoresis. The D12Z3 array has been measured by pulsed-field gel electrophoresis to span approximately 2,250–4,300 kb at the centromeric region of chromosome

ISSN:1424-8581    

DOI:10.1159/000133071

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A number of apparent telomeric associations/ fusions (TAs) involving Yq12 were observed in a lymphoblastoid cell line (GM6892A) established from a fragile-X-negative, phenotypically normal male with the fragile X gene mutation. The TAs were seen when these cells were grown for an extended period of time in medium 199, which is deficient in thymidine and folic acid. Because the low thymidine and folic acid condition of medium 199 is known to induce chromosome and chromatid gaps and breaks at folate-sensitive fragile sites, other fragile site-induction regimes were examined to determine if the TAs seen in GM6892A were due to a fragile site in the Yq12 band. No TAs were seen with any of the other regimes that were tried.

ISSN:1424-8581    

DOI:10.1159/000133072

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

DNA from a male fetus with an interstitial deletion of 7q22 [(46, XY, del(7)(pter→q22.10::q31.10→qter)] was analyzed using probes in this region of 7q. The results localize plasminogen activator inhibitor type I (PLANHl) to 7q22.1→q22.3 and β-glucuronidase to band

ISSN:1424-8581    

DOI:10.1159/000133073

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Two bovine DNA probes (LCa and LCb) complementary to the clathrin light chain genes were hybridized to DNAs from bovine hamster hybrid somatic cell lines retaining different combinations of bovine chromosomes. Concordancy of retention of the clathrin genes was compared to existing syntenic data for the domestic cow. LCb, identified a single locus, CLTB, concordant with the genes encoding bovine anti-Müllerian hormone (AMH) and bovine osteonectin from bovine syntenic group U22. LCa recognized two loci, CLTAL1 from a previously unidentified bovine syntenic group, U25, and CLTAL2 which is concordant with GGTB2, a gene marker for bovine syntenic group U18

ISSN:1424-8581    

DOI:10.1159/000133074

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The human gene for tryptophan hydroxylase has panel of somatic cell hybrids. We report here on the refinement been previously assigned to chromosome 11 by analysis of a of this localization by in situ hybridization.

ISSN:1424-8581    

DOI:10.1159/000133075

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The full-length cDNA of the receptor for human AA-type platelet-derived growth factor (PDGF) was used to assign the PDGFRA gene to region q11→q21 of human chromosome 4 and to mouse Chromosome 5 by somatic cell hybrid analysis. Since the same region also contains the c-kit oncogene homolog KIT, we carried out pulsed-field gel electrophoresis to determine the physical distance between the two genes in human DNA. The two probes, when successively applied to the same filters, hybridized to a 450-kb EagI-fragment but not to other common restriction fragments. The genes are separated by at least one Notl, one Xhol, and one Sail sit

ISSN:1424-8581    

DOI:10.1159/000133076

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Tay-Sachs disease results from a mutation in the α subunit of β-hexosaminidase. Using a cDNA clone, we have mapped the gene to 15q23→q24 by in situ hybridizat

ISSN:1424-8581    

DOI:10.1159/000133077

出版商:S. Karger AG    

年代:1991

数据来源: Karger