OR = 0.94 (95% CI = 0.90–0.98); P for difference = 3.1 × 10−10). No such difference was observed for the neighboring SNP rs11814448, which was associated with both ER-positive and ER-negative disease in the same direction. For one locus, SNP rs17817449 on chromosome 16, the association was stronger for ER-negative than for ER-positive disease (P for difference = 0.039). All SNPs showed comparable ORs for invasive and in situ disease (based on data from 2,335 ductal carcinoma in situ, DCIS, and 42,118 invasive cases), with the exceptions of rs12493607 and rs3903072, for which associations seemed to be restricted to invasive disease (Supplementary Table 7b). Two loci (rs2588809 at 14q24.1 (P = 0.001) and rs941764 at 14q32.12 (P = 0.007)) showed higher per-allele ORs for cases diagnosed at a young age (Supplementary Table 7c). Consistent with the predictions of a polygenic model of susceptibility25, for 26 of the loci, the estimated OR was higher when restricted to cases with a positive family history for disease (significant at P < 0.05 for 5 loci), whereas for only 6 loci was the OR lower when restricted to cases with a positive family history (Supplementary Table 7d).
