Using genetically determined ancestry of European rather than self-described race of White, postmenopausal patients with ER-positive breast cancer had 26/185 = 14.1% adrenal-permissive genotype, and ER-negative had 5/94 = 5.3% adrenal-permissive genotype (P = 0.0574 for ER-positive vs. control cohort and P = 0.0278 for ER-positive vs. ER-negative). This evidence concerns the gene ESR1 and breast cancer.