LOSS OF HETEROZYGOSITY AND LINKAGE ANALYSIS IN BREAST-CARCINOMA - INDICATION FOR A PUTATIVE 3RD SUSCEPTIBILITY GENE ON THE SHORT ARM OF CHROMOSOME-8

We have analysed losses of heterozygosity (LOH) at eight markers from the p12-p22 region of human chromosome 8 in a panel of 113 breast tumo rs. LOH were detected in almost half of the tumors. The most frequentl y deleted region included microsatellite (CA)n repeats markers D8S258, D8S133 and D8S259, located at 8p12-p22, while markers NEFL and LPL ap peared less frequently altered. In parallel, linkage analysis was perf ormed using the same informative markers, to test for the involvement of chromosome 8p loci in familial breast cancer. Positive cumulative m ultipoint lod score of 2.51 at Theta=0.0 was obtained with markers NEF L and D8S259. These results suggest that region 8p12-p22 carries at le ast one tumor suppressor gene involved in sporadic and perhaps also in familial breast cancer.