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A Nothnagel

Publications and source records attributed to A Nothnagel.

8 recordsLinked to original sources

Detailed deletion mapping in sporadic breast cancer at chromosomal region 17p13 distal to the TP53 gene: association with clinicopathological parameters.

Chromosome 17p is among the most frequently deleted regions in a variety of human malignancies including breast cancer. This study has further refined the localization of a putative tumour suppressor gene (TSG) at 17p13 distal to the TP53 gene in breast carcinomas. It was found that 73% (37 of 51) of the breast tumours exhibited loss of heterozygosity (LOH) at one or more loci at 17p13. The allelic loss patterns of these tumours suggest the presence of at least seven commonly deleted regions on 17p13. The three most frequently deleted regions were mapped at chromosomal location 17p13.3-17p13.2 between the markers D17S831 and D17S1845 (56% LOH), at 17p13.1 between D17S1810 and D17S1832 (53% LOH), and at 17p13.1 between D17S938 and TP53 (55% LOH). A significant correlation was found between loss at 17p13 and tumour grade, size, proliferative activity, and oestrogen receptor (ER) status. Losses at 17p13 were seen more frequently in large and poorly differentiated tumours with high proliferative activity. These data support and extend previous reports on the presence of a putative TSG(s) at chromosomal region 17p13 distal to the TP53 gene and show that different subsets of LOH are associated with more aggressive tumour behaviour.

Adult↗

Refined deletion mapping in sporadic breast cancer at chromosomal region 8p12-p21 and association with clinicopathological parameters.

We have further refined the loss of heterozygosity (LOH) pattern on the human chromosomal region 8p12-p21 using 15 well characterised microsatellite markers in a panel of 50 breast carcinomas. The allelic loss pattern of these tumours suggests the presence of five commonly deleted regions on 8p12-p21. The most commonly deleted region was located between markers D8S1734 and D81989, spanning a distance of approximately 3 cM and reaching 56% LOH at locus NEFL. LOH at 8p12-p21 was significantly correlated with large tumour size (T>5 cm). Patients with the age at diagnosis of breast cancer between 45 and 55 years showed significantly more LOH than patients older than 55 years or younger than 45 years. No correlation was observed between 8p12-p21 alterations and histological tumour type, grade and the presence of lymph node metastases.

Adult↗

Strong indication for a breast cancer susceptibility gene on chromosome 8p12-p22: linkage analysis in German breast cancer families.

Chromosomal losses involving the short arm of chromosome 8 are frequent in a variety of tumor types, including breast cancer, suggesting the presence of one or more tumor suppressor genes in this region. Previous linkage analysis and studies of loss of heterozygosity (LOH) have suggested the presence of a putative third breast cancer susceptibility gene around D8S505 at 8p12-p22. We have performed linkage analysis in two German breast cancer families, showing negative lod scores with 17q and 13q markers, using seven adjacent microsatellite markers from 8p12-p22. Incorporating LOH data from tumors of the affected family members a maximum cumulative three-point lod score of 3.30 at theta = 0.00 was obtained with D8S137 and D8S131. Our findings considerably strengthen the evidence for a third breast cancer susceptibility locus (BRCA3) mapping to the short arm of human chromosome 8.

Adult↗

BRCA1 mutations and phenotype.

More than 100 mutations have been described for the breast-cancer-susceptibility gene BRCA1. The paper describes phenotypical aspects of three selected mutations located at the beginning, in the middle, and at the end of the gene. A remarkable decrease of the age of diagnosis of the mammary carcinoma is observed with increasing length of the putative gene product, combined with greater severity of the disease.

Adult↗

Deletion mapping and linkage analysis provide strong indication for the involvement of the human chromosome region 8p12-p22 in breast carcinogenesis.

We have identified a high frequency of loss of heterozygosity (LOH) on the human chromosome region 8p12-p22 in a panel of microdissected familial (86% LOH) and sporadic (74% LOH) breast tumours. The two most frequently deleted regions were defined around marker D8S133 and in a broader centromeric region bounded by markers D8S137 and D8S339. We cannot unequivocally characterize the 8p12-p22 loss as an early or a late event in breast carcinogenesis. In parallel, we have performed linkage analysis in four German breast cancer families. A location score greater than 13.67 corresponding to a LOD score of 2.97 at the marker D8S137 has been obtained. Our results considerably strengthen the evidence for a breast cancer susceptibility gene(s) located on the short arm of the chromosome region at 8p12-p22.

Adult↗

BRCA1 mutations in German breast-cancer families.

We analyzed germline mutations of the BRCA1 gene in 20 German breast/ovarian-cancer families. BRCA1 mutations co-segregating with breast-cancer susceptibility were identified in 3 of these families. All mutations were found to generate a premature stop codon leading to the synthesis of truncated BRCA1 proteins of different length. Nine polymorphisms were detected in BRCA1, 4 of which have not been described previously. Analysis of familial tumors for LOH revealed that only the disease-related allele of BRCA1 was present.

Adult↗

X-ray scattering evidence that calf thymus DNA in solution is a double helix and not a warped zipper.

Isotropic X-ray scattering experiments with calf thymus DNA in solution under B-form conditions were used to differentiate between the double helical and the side by side structure models. By comparison of experimental and theoretical scattering curves calculated from the atomic coordinates of the molecule models, two sterically refined SBS models can be excluded for calf thymus DNA. The structural basis of the differences between the experimental scattering curves and the theoretical curves for the double helix on the one hand and for the two SBS models on the other, is interpreted using high resolution electron distance distribution functions of the models.

Animals↗