LINKAGE TO MARKERS FOR THE CHROMOSOME REGION 17Q12-Q21 IN 13 DUTCH BREAST-CANCER KINDREDS

We have performed linkage analysis with five markers for the chromosom e region 17q12-q21 in 13 Dutch breast cancer kindreds in order to find support for the claim by Hall et al. that a gene in this region, term ed ''BRCA1,'' is associated with predisposition to early-onset familia l breast cancer. This work is part of a collaborative study, the resul ts of which are published elsewhere in this issue. Best evidence for l inkage was observed with the marker CMM86 (D17S74) in pedigrees with a n average age at onset of less-than-or-equal-to 47 years (LOD score = 1.77 at 1% recombination). In one breast-ovarian cancer family with a high probability of being linked to 17q, we observed one putative reco mbinant between D17S250 and D17S579, which suggests that BRCA1 is prox imal to D17S579.