BRCA1 and breast carcinoma: For example, previvors with a P/LP in the BRCA1 gene have up to a 72 % lifetime breast cancer risk and up to a 44 % lifetime ovarian cancer risk; however, previvors with a P/LP in the BRCA2 gene have up to a 69 % lifetime breast cancer risk and a 17 % lifetime ovarian cancer risk [2].