A PHYSICAL MAP AND CANDIDATE GENES IN THE BRCA1 REGION ON CHROMOSOME 17Q12-21

We have constructed a physical map of a 4 cM region on chromosome 17q1 2-21 that contains the hereditary breast and ovarian cancer gene BRCA1 . The map comprises a contig of 137 overlapping yeast artificial chrom osomes and P1 clones, onto which we have placed 112 PCR markers. We ha ve localized more than 20 genes on this map, ten of which had not been mapped to the region previously, and have isolated 30 cDNA clones rep resenting partial sequences of as yet unidentified genes. Two genes th at lie within a narrow region defined by meiotic breakpoints in BRCA1 patients have been sequenced in breast cancer patients without reveali ng any deleterious mutations. These new reagents should facilitate the identification of BRCA1.