Most inherited cases of breast cancer are associated with two abnormal genes: BRCA1 (BReast CAncer gene 1) and BRCA2 (BReast CAncer gene 2). According to the National Cancer Institute, women with an abnormal BRCA1 or BRCA2 gene have about a 60% risk of being diagnosed with breast cancer during their lifetimes (compared to about 12% for women overall). Their risk of ovarian cancer is also increased. Abnormal BRCA1 or BRCA2 genes are found in 5% to 10% of all breast cancer cases in the United States. Other types of inherited gene abnormalities are less common. Finding out whether you have.
