The study population consisted of 530 postmenopausal sporadic breast cancer cases, 165 familial breast cancer cases (including N = 20, who test positive for BRCA1 mutations and N = 9, who test positive for BRCA2 mutations) and 270 postmenopausal control women with no history of breast and/or ovarian cancer. The gene discussed is BRCA1; the disease is breast carcinoma.