A SOMATIC-CELL HYBRID MAP OF THE LONG ARM OF HUMAN CHROMOSOME-17, CONTAINING THE FAMILIAL BREAST-CANCER LOCUS (BRCAI)

We describe a detailed somatic cell hybrid map of human chromosome 17q 11.2-q23, containing the familial breast and ovarian cancer locus (BRC A1) and highly informative closely linked markers. An X-irradiation pa nel of 38 hamster/human and mouse/human hybrids with fragments of chro mosome 17 was generated and characterized with 22 STS markers from thi s chromosome. A detailed map of 61 probes onto chromosome 17q, subdivi ding the chromosome arm into 25 regions, was done by using a panel of hybrids with well-defined breakpoints and nine chromosome-mediated gen e transfectants. Our localization of RARA, TOP2, EDH17B1 and 2, and po ssibly WNT3, between THRA1 and D17S181, two markers known to flank BRC A1, suggests that any of these is a potential candidate for the BRCA1 locus. The marker D17S579 (Mfd188), which is believed to be very close to BRCA1, maps closest to the EDH17B genes.