Since the establishment of predisposing effects of BRCA1 (MIM:113705) and BRCA2 (MIM: 114480) to breast/ovarian cancers, we have accumulated understandings of the biological roles of BRCA1/2 and their prevalence of mutations in different ethnic populations through a lot of functional experiments and sample-based studies. This evidence concerns the gene BRCA1 and ovarian cancer.