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1.
Ruxandra Ion L. Telvi Jean-Louis Chaussain Jacques Patrick Barbet Manoel Nunes Anne Safar Marie-Odile Réthoré Marc Fellous Ken McElreavey 《Human genetics》1998,102(2):151-156
In 46,XY individuals, testes are determined by the activity of the SRY gene (sex-determining region Y), located on the short arm of the Ychromosome. The other genetic components of the cascade
that leads to testis formation are unknown and may be located on the Xchromosome or on the autosomes. Evidence for the existence
of several loci associated with failure of male sexual development is indicated by reports of 46,XY gonadal dysgenesis associated
with structural abnormalities of the Xchromosome or of autosomes (chromosomes9, 10, 11 and 17). In this report, we describe
the investigation of a child presenting with multiple congenital abnormalities, mental retardation and partial testicular
failure. The patient had a homogeneous de novo 46,XY,inv dup(9)(pter→p24.1::p21.1 →p23.3::p24.1→qter) chromosome complement.
No deletion was found by either cytogenetic or molecular analysis. The SRY gene and DSS region showed no abnormalities. Southern blotting dosage analysis with 9p probes and fluorescent in situ hybridisation data
indicated that the distal breakpoint of the duplicated fragment was located at 9p24.1, proximal to the SNF2 gene. We therefore suggest that a gene involved in normal testicular development and/or maintenance is present at this position
on chromosome 9.
Received: 20 January 1997 / Accepted: 5 November 1997 相似文献
2.
3.
Matilde Jose Isabelle Tratner Maryse Poiret Jean-Louis Nahon Jean-Louis Danan Jose Maria Sala-Trepat 《Molecular & general genetics : MGG》1989,215(2):225-230
Summary The distribution of middle repetitive sequences in the genic and extragenic regions of the rat albumin and -fetoprotein genes was analyzed. Their presence was determined by probing Southern blots of restriction fragments of albumin and -fetoprotein genomic subclones with 32P-labeled total rat DNA. Repetitive sequences were detected in both genes. They were classified as weak, moderate and intense hybridizing elements according to the intensity of hybridization. Weak repetitive sequences were characterized as dG·dT repeats by using 32P-labeled poly-(dG·dT)(dC·dA) oligomer probe. They occurred in 5 and 3 extragenic regions of the two genes and in introns 4 and 5 of the albumin gene. The moderate repetitive sequence present in intron 6 of the albumin gene was identified as the rat SINES element, 4D12. The intense repetitive sequence, localized in the 3 non-coding region of the albumin gene, corresponded to the terminal segment of a rat high repeat long interspersed DNA family, L1Rn. 4D12 and L1Rn sequences were also scattered throughout the -fetoprotein locus as moderate and intense repetitive elements, respectively, but their distribution was different from that of the albumin genomic region. These results indicate that repetitive sequences invaded the two loci in a non-conservative manner. 相似文献
4.
Genetic convergence during serial in vitro passage of a polyclonal squamous cell carcinoma 总被引:1,自引:0,他引:1
A cell line was established from an in situ squamous cell carcinoma of the skin (Bowen's disease), and its in vitro karyotypic evolution was cytogenetically analyzed. Initially, considerable genetic heterogeneity was evident. Nine cytogenetically abnormal clones, eight of which were apparently unrelated, were found among the 83 metaphases analyzed from the primary culture and the first passage. With increasing time in culture this complexity was reduced, so that a single clone dominated passages 7-11. The clone that emerged from this genetic convergence had a t(12;17)(p13;q21) as the sole abnormality. Our findings indicate that the cytogenetic multiclonality that has been repeatedly detected in short-term cultures of squamous cell carcinomas is not caused by the in vitro conditions. Instead, the principles of Darwinian selection apply: the altered, but stable, selection pressure facing a newly established and initially multiclonal cell line will lead to a reduction of genetic heterogeneity until the one clone that now has the proliferative advantage outgrows the other subpopulations. 相似文献
5.
Mef Nilbert Sverre Heim Nils Mandahl Ulla-Maria Flodérus Helena Willén Felix Mitelman 《Human genetics》1990,85(6):605-611
Summary The cytogenetic analysis of 224 leiomyomas from 138 patients is presented. An insufficient number of mitoses was found in 35 tumors, normal karyotypes in 145, and clonal chromosome aberrations were detected in 44. The three previously identified cytogenetic subgroups were all represented in this series: del(7) (q21.2q31.2) was found in 11, trisomy 12 in five, and t(12;14)(q14-15;q23-24) in one leiomyoma. Rearrangements of 6p, including deletions, inversions, and various translocations, were found in eight tumors, thus delineating a new cytogenetic subgroup of uterine leiomyoma. The remaining 21 karyotypically abnormal tumors had nonrecurrent changes. One leiomyoma had two cytogenetically unrelated clones characterized by del(7)(q21.2 q31.2) and +12. Karyotypic changes in two separate leiomyomas from the same uterus were identified in five patients; in three of them, different anomalies were found in the two tumors, whereas cytogenetically identical aberrations – del(7q) and dic(21;22) – were detected in two macroscopically discrete tumors. These findings suggest that whereas some multiple leiomyomas originate independently, others may be derived from the same neoplastic clone. 相似文献
6.
Chromosome localization and polymorphism of an oestrogen-inducible gene specifically expressed in some breast cancers 总被引:3,自引:0,他引:3
Summary The BCEI gene codes for a small secreted protein and is expressed in the human mammary tumour cell line MCF7 under oestrogen control and in some breast cancers. We have mapped the gene to chromosome 21 using a panel of somatic hybrid lines, and in situ hybridization has allowed a precise assignment to band 21q223. Two restriction fragment length polymorphisms (RFLP) are described that should be of use in linkage or population studies to test a possible involvement of the BCEI gene in genetic predisposition to breast cancer. This gene should also be a useful marker for the genetic and physical mapping of chromosome 21, and for a better definition of the region involved in the clinical phenotype of Downs syndrome. 相似文献
7.
Hugues Puissant Martine Azoulay Jean-Louis Serre LucLarget Piet Claudine Junien 《Human genetics》1988,79(3):280-282
Summary Most patients with the complex association aniridia — predisposition to Wilms' tumor (WAGR syndrome) present with a de novo constitutional deletion of band 11p13. We report a patient with WAGR syndrome and a reciprocal translocation between chromosomes 5 and 11 t(5;11)(q11;p13). High resolution banding cytogenetic analysis and molecular characterization using 11p13 DNA markers showed a tiny deletion encompassing the gene for CAT but sparing the gene for FSHB. This suggests that syndromes associated with apparently balanced translocations may be due to undetectable loss of material at the breakpoint(s) rather than to breakage in the gene itself. 相似文献
8.
The swi4+ gene of Schizosaccharomyces pombe encodes a homologue of mismatch repair enzymes. 总被引:5,自引:5,他引:0
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The swi4+ gene of Schizosaccharomyces pombe is involved in termination of copy-synthesis during mating-type switching. The gene was cloned by functional complementation of a swi4 mutant transformed with a genomic library. Determination of the nucleotide sequence revealed an open reading frame of 2979 nucleotides which is interrupted by a 68 bp long intron. The putative Swi4 protein shows homology to Duc-1 (human), Rep-3 (mouse), HexA (Streptococcus pneumoniae) and MutS (Salmonella typhimurium). The prokaryotic proteins are known as essential components involved in mismatch repair. A strain with a disrupted swi4+ gene was constructed and analysed with respect to the switching process. As in swi4 mutants duplications occur in the mating-type region of the swi4 (null) strain, reducing the efficiency of switching. 相似文献
9.
Marie-Laure Yaspo Nathalie Crété Zoubida Chettouh Jean-Louis Blouin Zohra Rahmani Dominique Stehelin Pierre-Marie Sinet Nicole Créau-Goldberg Jean-Maurice Delabar 《Human genetics》1992,90(4):427-434
To generate new chromosome 21 markers in a region that is critical for the pathogenesis of Down syndrome (D21S55-MX1), we used pulsed field gel electrophoresis (PFGE) to isolate a 600-kb NruI DNA fragment from the WA17 hybrid cell line, which has retained chromosome 21 as the only human material. This fragment, which contains the oncogene ETS2, was used to construct a partial genomic library. Among the 14 unique sequences that were isolated, 3 were polymorphic markers and contained sequences that are conserved in mammals. Five of these markers mapped on the ETS2-containing NruI fragment and allowed us to define an 800-kb high-resolution PFGE map. 相似文献
10.