The average lifetime risks for women of developing breast cancer and ovarian cancer are 1 in 8 and 1 in 78, respectively [1,3]; however, studies have shown that women with inherited breast cancer 1 gene (BRCA1) and breast cancer 2 gene (BRCA2) carriers have substantially increasing lifetime risk of developing breast cancer and ovarian cancer, with a lifetime risk of 56% to 84% for breast cancer [4,5,6,7] and 36% to 63% for ovarian cancer for BRCA1 variant carriers and 10% to 27% for BRCA2 carriers [4,5,8,9,10]. Here, BRCA1 is linked to breast cancer.