GNB3 and breast carcinoma: Two SNPs showed an association with breast cancer: R72P inTP53 and P187S in NQO1. Six SNPs, Q356R and P871L in BRCA1, N372H in BRCA2, C112R (E4) and R158C (E2) in ApoE and C825T in GNB3, did not show any sign of association.