Biomedical subjects

J Weissenbach

Publications and source records attributed to J Weissenbach.

At least 163 records · Page 9Linked to original sources

PubMed1995

A 11 Mb YAC-based contig spanning the familial juvenile nephronophthisis region (NPH1) located on chromosome 2q.

A gene (NPH1) responsible for approximately 90% of the purely renal form of familial juvenile nephronophthisis, a progressive tubulo-interstitial kidney disorder, maps to human chromosome 2. We report the construction of a YAC-based contig spanning the critical NPH1 region and the flanking genetic markers. This physical map was integrated with a refined genetic map that restricted the NPH1 interval to about 2 cM; this interval corresponds to a maximum physical distance of 3.5 Mb. The entire contig covers 9 cM between the loci D2S135 and D2S121. The maximum physical distance between these two markers is approximately 11.3 Mb. Forty-five sequence-tagged sites, including six genes, have been located within this contig. PAX8, a member of the human paired box gene family, that is expressed in the developing kidney, was assigned outside the restricted NPH1 critical region and cannot therefore be regarded as a candidate gene. This set of overlapping clones represents a useful resource for further targeted development of genetic markers and for the characterization of candidate genes responsible for juvenile nephronophthisis.

Base Sequence↗

PubMed1995

The role of SOX9 in autosomal sex reversal and campomelic dysplasia.

In eutherian mammals, the Y-chromosome gene SRY is required for induction of testis development. Although the Y chromosome is sex determining, loci located elsewhere in the genome participate in the complex cascade of genetic interactions required to form a testis. Male to female sex reversal (46,XY females) occurs at a high frequency in individuals afflicted with the skeletal malformation syndrome campomelic dysplasia. Chromosomal translocations in individuals with both syndromes had localized an autosomal sex reversal locus (SRA1) and a campomelic dysplasia locus (CMPD1) to the long arm of human chromosome 17. The molecular cloning of a translocation breakpoint in a sex reversed campomelic dysplasia patient revealed its proximity to SOX9, a gene which is related to SRY. Analysis of SO X9 in patients without chromosomal rearrangements demonstrated single allele mutations in sex reversed campomelic individuals, linking this gene with both bone formation and control of testis development. Identification of SO X9 as SRA1/CMPD1 and the role of SO X9 mutations in sex reversal and campomelic dysplasia are discussed.

Biological Evolution↗

PubMed1995

Identification and cloning in yeast artificial chromosomes of a region of elevated loss of heterozygosity on chromosome 1p31.1 in human breast cancer.

We have mapped a region of high loss of heterozygosity in breast cancer to a 2-cM interval between the loci D1S430 and D1S465 on chromosome 1p31.1. This region shows allelic imbalance in around 60% of breast tumors. As part of a strategy to clone the target gene(s) within this interval, we have generated a yeast artificial chromosome contig spanning over 7 Mb. YACs from the CEPH and Zeneca (formerly ICI) libraries have been obtained by screening with PCR-based STSs from the region for both previously identified loci and newly isolated STSs. The YACs have been assembled into a contig by a combination of approaches, including analysis of their STS content, generation of new STSs from the ends of key YACs, and long-range restriction mapping. These YAC clones provide the basis for complete characterization of the region of high loss in breast cancer and for the ultimate identification of the target gene(s).

Base Sequence↗

PubMed1995

Loss of heterozygosity in the chromosomal region 12p12-13 is very common in childhood acute lymphoblastic leukemia and permits the precise localization of a tumor-suppressor gene distinct from p27KIP1.

Abnormalities of the short arm of chromosome 12 are relatively common in hematologic malignancies and deletions of the region. 12p12-13 are found in approximately 5% of the patients with acute lymphoblastic leukemia (ALL). As a potent inhibitor of cyclin-dependent kinases, p27KIP1 prevents the progression of the cell cycle and the gene encoding p27KIP1 represents a potential tumor-suppressor gene. Its recent assignment to the chromosomal region (12p12.3) prompted us to study the p27KIP1 gene in a series of 61 children with ALL. Microsatellite polymorphic markers flanking the p27KIP1 gene were analyzed to detect losses of heterozygosity (LOH). Eleven patients displayed LOH for at least one of the markers. The deleted are encompassed the p27KIP1 gene locus in 10 cases, but inactivation of the remaining allele by deletion, translocation, or mutation was never observed. In addition, in 1 patient, the p27KIP1 gene was situated outside of the region of LOH. Thus, p27KIP1 does not seem to be the target gene of 12p12-13 alterations. However, this study indicates that 12p12-13 alterations at the molecular level, which are present in about 27% of the children with B-lineage ALL, are much more common than had previously been reported by usual chromosome analysis. Moreover, LOH mapping allowed us to better define the location of a putative tumor-suppressor gene implicated in these malignancies and should therefore help in identifying this gene.

Base Sequence↗

PubMed1995

Loss of the chromosomal region 10q23-25 in prostate cancer.

Loss of the chromosomal region 10q23-25 is a frequent event in the progression of prostate adenocarcinoma. A candidate tumor suppressor gene from this region, Mxi1 at 10q25, has recently been shown to be mutated in a small number of prostate tumors. To more strictly define those regions of 10q loss that are likely to be involved in tumor advancement, we have constructed a detailed deletion map spanning 10q23-25 that incorporates Mxi1. Sixty-two % (23 of 37) of tumors analyzed exhibited some degree of 10q23-25 loss. Our data suggest the presence of a prostate tumor suppressor gene(s) near the 10q23-24 boundary, which was deleted in the overwhelming majority (22 of 23) of tumors showing loss. In contrast, specific loss of Mxi1, as opposed to loss of other 10q23-25 regions or of the entire region, was observed in only 1 of 23 tumors and was accompanied by loss of markers at the 10q23-24 boundary. Furthermore, we failed to detect any mutations in Mxi1 in those tumors showing Mxi1-associated marker loss by either single-strand conformation polymorphism analysis or direct DNA sequencing.

Aged↗

PubMed1995

Physical mapping of the human ELA1 gene between D12S361 and D12S347 on chromosome 12q13.

ELA1, the pancreatic elastase 1 gene, is conserved in mammalian genomes. ELA1 was previously mapped to chromosome 12 using a panel of mouse-human somatic cell hybrids. We now report the physical and cytogenetic localization of the ELA1 gene. On the physical map, ELA1 is adjacent to the polymorphic marker AFMa283yg1 and between D12S361 and D12S347. Using fluorescence in situ hybridization, we determined that ELA1 maps to 12q13.

Animals↗

PubMed1995

A second-generation YAC contig map of human chromosome 3.

A map of human chromosome 3 which integrates both physical and genetic data has been developed from the fusion of two large collections of markers and corresponding yeast artificial chromosome (YAC) clones. The map contains 972 megabase-sized YACs identified with 593 primary markers, of which 162 are highly polymorphic sequence-tagged sites (STSs) and form a closely spaced genetic linkage map; the remaining markers are hybridization-based. Chromosome 3 is now represented by 24 large YAC contigs whose order and orientation is largely known. The map generated by fusion of these hybridization- and STS-based datasets covers about 80% (over 160 megabases) of the chromosome and will provide the foundation necessary for rapid development of a detailed genetic understanding for this large autosome.

Chromosome Mapping↗

PubMed1995

Precise mapping of t(12;14) leiomyoma breakpoint on chromosome 14 between D14S298 and D14S540.

Uterine leiomyoma is a common tumor of smooth muscle cell origin often characterized by the presence of a balanced t(12;14)(q13-15;q24.1) chromosomal translocation. This breakpoint on chromosome 14 had previously been placed between the markers SPTB and D14S77, a region estimated to span 7 cM. In this study we have used a meiotic breakpoint mapping panel to construct a high resolution genetic map of this interval. Markers that mapped within this interval were used to analyze DNA from a somatic cell hybrid containing the t(12;14) translocated chromosome. The results of this analysis localize the t(12;14) breakpoint on chromosome 14 between D14S298 and D14S540, between which no meiotic recombination was detected. This sets the stage for identifying the gene(s) disrupted by the chromosomal translocation by defining the markers that flank the translocation breakpoint.

Base Sequence↗

PubMed1995

A YAC contig and an EST map in the pericentromeric region of chromosome 13 surrounding the loci for neurosensory nonsyndromic deafness (DFNB1 and DFNA3) and limb-girdle muscular dystrophy type 2C (LGMD2C).

Two forms of inherited childhood nonsyndromic deafness (DFNB1 and DFNA3) and a Duchenne-like form of progressive muscular dystrophy (LGMD2C) have been mapped to the pericentromeric region of chromosome 13. To clone the genes responsible for these diseases we constructed a yeast artificial chromosome (YAC) contig spanning an 8-cM region between the polymorphic markers D13S175 and D13S221. The contig comprises 24 sequence-tagged sites, among which 15 were newly obtained. This contig allowed us to order the polymorphic markers centromere-D13S175-D13S141-D13S143-D13S115-AF M128yc1-D13S292-D13S283-AFM323vh5- D13S221-telomere. Eight expressed sequence tags, previously assigned to 13q11-q12 (D13S182E, D13S183E, D13S502E, D13S504E, D13S505E, D13S837E, TUBA2, ATP1AL1), were localized on the YAC contig. YAC screening of a cDNA library derived from mouse cochlea allowed us to identify an alpha-tubulin gene (TUBA2) that was subsequently precisely mapped within the candidate region.

Animals↗

PubMed1995

A YAC contig spanning the dominant retinitis pigmentosa locus (RP9) on chromosome 7p.

The dominant retinitis pigmentosa locus RP9 has previously been localized to 7p13-p15, in the interval D7S526-D7S484. We now report refinement of the locus to the interval D7S795-D7S484 and a YAC contig of approximately 4.8 Mb spanning this region and extending both distally and proximally from it. The contig was constructed by STS content mapping and physically orders 29 STSs in 28 YAC clones. The order of polymorphic markers in the contig is consistent with a genetic map that has been assembled using haplotype data from the CEPH pedigrees. This contig will provide a primary resource for the construction of a transcriptional map of this region and for the identification of the defective gene causing this form of adRP.

Base Sequence↗

PubMed1995

A radiation hybrid map of 95 STSs spanning human chromosome 13q.

We have constructed a high-resolution physical map of the long arm of human chromosome 13 using a panel of 94 radiation hybrids. A comprehensive map of 95 chromosome 13-specific sequence tagged sites (STSs) spanning 13q from the presumed centromere at D13Z1 to the known telomere was obtained by multipoint maximum likelihood statistical methods. The 95 markers have an average retention frequency of 10%, with markers closer to the centromere having much greater retention frequencies (22-49%) than distal 13q markers (2-12%). The most likely radiation hybrid map localized the 95 STSs into 54 unique map positions, 34 with odds of 1000:1 or greater; the comprehensive map localized all but 17 STSs with odds exceeding 10:1. The total map length of 13q was 1302 cR9000 (range 6.4-94.4 cR9000) and a physical distance of 98 Mb, so that 1% breakage in the RH panel corresponds to 75 kb. A comparison of the comprehensive RH map to genetic maps of chromosome 13q shows identical locus orders for the common markers, with two exceptions over 1-cM distances. We discuss the possible relationships between the genetic and the radiation hybrid maps.

Animals↗

PubMed1995

Linkage disequilibrium utilized to establish a refined genetic position of the Salla disease locus on 6q14-q15.

Salla disease (SD), an inherited free sialic acid storage disorder, is caused by impaired transport of free sialic acid across the lysosomal membrane. Clinical characteristics of the disease include severe psychomotor retardation and some neurological abnormalities. We report here detailed linkage analyses of 50 Finnish SD families that localize the SD disease gene to a refined chromosomal area on 6q14-q15. The highest lod score of 17.30 was obtained with a microsatellite marker of locus D6S280. When linkage disequilibrium was adopted in the linkage analyses, we could further assign the SD locus to the immediate vicinity of marker locus D6S406. Linkage disequilibrium facilitated further restriction of the critical chromosomal region to approximately 80 kb, well within the limits of positional cloning techniques.

Alleles↗

PubMed1995

Physical mapping of 30 CA repeats on human chromosome 22.

We report the physical mapping of 30 microsatellite markers specific for chromosome 22 by PCR amplification of DNA from hybrids that divide the long arm into 27 subregions. This work permits further refining of the genetic linkage ordering previously published.

Base Sequence↗

PubMed1995

The CEPH consortium linkage map of human chromosome 11.

The CEPH consortium framework map of chromosome 11 is presented. The map was generated from CEPH family DNAs with 181 probe/enzyme combinations contributed by 20 laboratories. Seventy-seven of the loci are defined by microsatellite polymorphisms that can be typed by the PCR. A total of 42 loci have been placed on the map with likelihood support of at least 1000:1. The female, male, and sex-average maps extend for 179.6, 110.8, and 145.3 cM, respectively. The largest interval on the sex-average map is less than 11 cM, and the average distance between uniquely placed loci is 4 cM. The genotypic data obtained for map construction have been used to identify the positions of crossovers on the chromosomes of CEPH family children, allowing the localization of new markers without computationally intensive likelihood models and providing a basis for efficient extension of the linkage map to higher resolution.

Adult↗

PubMed1995

High-density physical mapping of a 3-Mb region in Xp22.3 and refined localization of the gene for X-linked recessive chondrodysplasia punctata (CDPX1).

The study of patients with chromosomal rearrangements has led to the mapping of the gene responsible for X-linked recessive chondrodysplasia punctata (CDPX1; MIM 302950) to the distal part of the Xp22.3 region, between the loci PABX and DXS31. To refine this mapping, a yeast artificial chromosome (YAC) contig map spanning this region has been constructed. Together with the YAC contig of the pseudo-autosomal region that we previously established, this map covers the terminal 6 Mb of Xp, with an average density of 1 probe every 100 kb. Newly isolated probes that detect segmental X-Y homologies on Yp and Yq suggest multiple complex rearrangements of the ancestral pseudoautosomal region during evolution. Compilation of the data obtained from the study of individuals carrying various Xp22.3 deletions led us to conclude that the CDPX disease displays incomplete penetrance and, consequently, to refine the localization of CDPX1 to a 600-kb interval immediately adjacent to the pseudoautosomal boundary. This interval, in which 12 probes are ordered, provides the starting point for the isolation of CDPX1.

Base Sequence↗

PubMed1995

Cornea plana congenita gene assigned to the long arm of chromosome 12 by linkage analysis.

We report the mapping of the locus for autosomal recessive cornea plana congenita (CNA2; MIM 217300) by linkage analysis to the approximately 10-cM interval between markers D12S82 and D12S327. The recessively inherited disorder studied here is more severe than dominant forms. Its main manifestations are reduced curvature and hazy limbus of the cornea, opacities in the corneal stroma, and marked corneal arcus at early age. Our results provide a starting point for the positional cloning of CNA2 and the elucidation of the pathogenesis of the disease.

Adult↗

PubMed1995

The CEPH consortium linkage map of human chromosome 16.

A Centre d'Etude du Polymorphisme Humain (CEPH) consortium map of human chromosome 16 has been constructed. The map contains 158 loci defined by 191 different probe/restriction enzyme combinations or primer pairs. The marker genotypes, contributed by 9 collaborating laboratories, originated from the CEPH families DNA. A total of 60 loci, with an average heterozygosity of 68%, have been placed on the framework genetic map. The genetic map contains 7 genes. The length of the sex-averaged map is 165 cM, with a mean genetic distance between loci of 2.8 cM; the median distance between markers is 2.0 cM. The male map length is 136 cM, and the female map length is 197 cM. The map covers virtually the entire chromosome, from D16S85, within 170 to 430 kb of the 16p telomere, to D16S303 at 16qter. The markers included in the linkage map have been physically mapped on a partial human chromosome 16 somatic cell hybrid panel, thus anchoring the genetic map to the cytogenetic-based physical map.

Animals↗

PubMed1995

Allelic imbalance on chromosome 1 in human breast cancer. II. Microsatellite repeat analysis.

We have determined regions of allelic imbalance in human breast cancer cells using highly polymorphic microsatellite markers, which can be rapidly typed by the polymerase chain reaction (PCR) using very small amounts of DNA. It appears that there are several regions of chromosome I which may be the targets of allelic imbalance, including some regions which have been identified previously by different groups. The detail with which we have mapped these regions of imbalance is, however, much greater than has been previously reported, and we have been able to localise these regions to small intervals of the genome. In addition we have identified previously uncharacterised regions of allelic imbalance on chromosome arm 1p, one of which (at 1p22-31) is lost in a high proportion of malignant lesions. We are currently attempting to analyse this latter region in detail in order to identify and characterise the sequence(s) involved. Study of such regions should help us understand some of the mechanisms underlying the development and progression of breast cancer.

Alleles↗