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A Tanigami

Publications and source records attributed to A Tanigami.

60 records · Page 4Linked to original sources

Thirty-one new RFLP systems detected by twenty-four DNA markers on human chromosome 10.

Thirty-one new RFLP systems corresponding to 24 loci have been identified from a chromosome 10-specific cosmid library. Twelve of the markers on the proximal long arm (cen-q11.2) of this chromosome, including four RFLP systems for the RET locus, will be especially useful in efforts to identify the gene responsible for multiple endocrine neoplasia type 2A (MEN2A). The new panel of markers also may contribute to fine-scale mapping of tumor suppressor genes associated with glioblastoma multiforme or renal cell carcinoma, because allelic deletions in these tumors have implied the presence of a tumor suppressor gene(s) on chromosome 10.

Chromosomes, Human, Pair 10↗

Mapping of 262 DNA markers into 24 intervals on human chromosome 11.

We have extended our mapping effort on human chromosome 11 to encompass a total of 262 DNA markers, which have been mapped into 24 intervals on chromosome 11; 123 of the markers reveal RFLPs. These clones are scattered throughout the chromosome, although some clustering occurs in R-positive bands (p15.1, p11.2, q13, and q23.3). Fifty-two of the markers were found to contain DNA sequences conserved in Chinese hamster, and some of these 52 also cross-hybridized with DNA from other mammals and/or chicken. As the length of chromosome 11 is estimated at nearly 130 cM, the average distance between RFLP markers is roughly 1 cM. The large panel of DNA markers on our map should contribute to investigations of hereditary diseases on this chromosome, and it will also provide reagents for constructing either fine-scale linkage and physical maps or contig maps of cosmids or yeast artificial chromosomes.

Animals↗

Isolation and mapping of 62 new RFLP markers on human chromosome 11.

To obtain new RFLP markers on human chromosome 11 for a high-resolution map, we constructed a cosmid library from a Chinese hamster x human somatic hybrid cell line that retains only human chromosome 11 in a Chinese hamster genomic background. A total of 3,500 cosmids were isolated by colony hybridization with labeled human genomic DNA. DNA was prepared from 130 of these cosmid clones and examined for RFLP. In 62 of them, polymorphism was detected with one or more enzymes; four RFLPs were VNTR systems. All polymorphic clones were assigned to one of 22 intervals obtained by mapping on a deletion panel of 15 somatic hybrid cell lines containing parts of chromosome 11; 11 clones were finely mapped by in situ hybridization. Although RFLP markers were scattered on the whole chromosome, they were found predominantly in the regions of R-banding. These DNA markers will contribute to fine mapping of genes causing inherited disorders and tumor-suppressor genes that reside on chromosome 11. Furthermore, as one-third of the cosmid clones revealed a band or bands in Chinese hamster DNA, indicating sequence conservation, this subset of clones may be useful for isolating biologically important genes on chromosome 11.

Animals↗

Allelotype of breast cancer: cumulative allele losses promote tumor progression in primary breast cancer.

Allele loss on a specific chromosome has implied the existence of a tumor suppressor gene such as the p53 gene and the RB gene. In order to determine which chromosome(s) carries a tumor suppressor gene(s) that contributes to tumor progression in primary breast cancer, we analyzed the loss of heterozygosity for each autosomal chromosome arm by using 39 restriction fragment length polymorphism markers including 25 variable numbers of tandem repeat probes. In 79 primary breast cancers, we found the frequent loss on the long arm of chromosome 13 (21%), the long arm of chromosome 16 (45%), and the short arm of chromosome 17 (56%). Interestingly, breast cancers in which loss of both chromosomes 13q and 17p was detected showed more malignant histopathological features, and a group of the tumors in which chromosome 16q loss was detected presented with frequent lymph node metastasis. Furthermore, the result of the deletion mapping on chromosome 17p implied the existence of a tumor suppressor gene distal to the p53 gene as well as the p53 gene itself for primary breast cancer. These results suggest that at least 4 tumor suppressor genes exist on chromosomes 13q, 16q, and 17p for primary breast cancer.

Blotting, Southern↗

Single-allele correction of the Dmo1 locus in congenic animals substantially attenuates obesity, dyslipidaemia and diabetes phenotypes of the OLETF rat.

1. Whole-genome scans have identified Dmo1 as a major quantitative trait locus for dyslipidaemia and obesity in the Otsuka Long Evans Tokushima Fatty (OLETF) rat. 2. We have produced congenic rats for the Dmo1 locus through successive back-cross breeding with diabetic OLETF rats. Marker-assisted speed congenic protocols were applied to efficiently transfer chromosomal segments from non-diabetic Brown Norway (BN) rats into the OLETF background. 3. In the fourth generation of congenic animals, we observed a substantial therapeutic effect of the Dmo1 locus on lipid metabolism, obesity control and plasma glucose homeostasis. 4. We have concluded that Dmo1 primarily affects lipid homeostasis, obesity control and/or glucose homeostasis at fasting and is secondarily involved in glucose homeostasis after loading. 5. The results of the present study show that single-allele correction of a genetic defect of the Dmo1 locus can generate a substantial therapeutic effect, despite the complex polygenic nature of type II diabetic syndromes.

Alleles↗

HPV33 DNA in premalignant and malignant breast lesions in Chinese and Japanese populations.

The relationship between human papillomavirus (HPV) infection and breast cancer is controversial. In this study, paraffin-embedded tissue blocks prepared from 72 patients with benign, premalignant or malignant mammary lesions were randomly collected from the Shanghai region of China and Tokushima in Japan. DNA specimens extracted from all tissues were amplified by the polymerase chain reaction (PCR) using HPV16, 18 and 33 primers. Southern blot hybridization showed 19 cases to be positive for HPV33 DNA: The positive rate for HPV33 DNA in Chinese (41.7%) was significantly higher than in Japanese (11.1%) (P < 0.01): The positive rate for HPV33 DNA in invasive ductal carcinoma (34.1%) was higher than in benign or borderline mammary lesions (5%) (P < 0.02). There were no statistically significant difference among the relationship of the nuclear grade of breast cancers with HPV33 DNA-positivity. This is the first report of a positive correlation between HPV33 DNA and breast lesions in Chinese and Japanese populations. These results suggest that the infection by HPV33, but not HPV 16 or HPV 18, may be involved in breast hyperplastic lesions, especially breast cancer, in humans.

Adult↗