A second, independent validation carried out on the most significantly associated SNP (rs11638442) located within the CYP11A1 gene in 783 postmenopausal women with mammograms in the Mayo Clinic Breast Cancer Study yielded a P value of 0.88 (regression coefficient = -0.000507, 95% confidence interval = -0.07251 to 0.06237). This evidence concerns the gene CYP11A1 and breast cancer.