In the present study, we found that the frequency of BRCA1 and BRCA2 mutations was 23.3 % in our cohort of 133 Chinese women with familial breast/ovarian cancer, and the frequency of BRCA1 and BRCA2 mutations was 50 % in patients with a familial history of both breast cancer and ovarian cancer. This evidence concerns the gene BRCA2 and breast cancer.