There are two main types of genes that play a role in cancer: oncogenes and tumor suppressor genes. Proto-oncogenes are regular genes that can become oncogenes if mutated and an oncogene is a gene that can lead to a tumor when mutated because it causes cells to divide unrestrainedly (Heidi 2008). In contrast, tumor suppressor genes slow cell division. When tumor suppressor genes do not function properly, cells can grow as quickly as an oncogene (Heidi 2008). Tumor suppressor genes involve the BRCA1 and BRCA2 genes present in breast cells (Klugar & Park 2013). Certain mutations in each may increase the risk of ovarian or pancreatic cancer (Klugar & Park 2013). Most breast cancers are hereditary, but they can also be acquired. Unlike proto-oncogenes, the American Cancer Society article on cancer states that most tumor suppressor gene mutations are acquired rather than hereditary. Acquired mutations of the TP53 gene encode the p53 protein and appear in various cancers, such as lung and breast cancer (“Oncogenes, Tumor Suppressor,” 2011). Cells with damaged DNA continue to divide and can eventually lead to cancer if the p53 protein gene does not function properly (“Oncogenes, tumor suppressor,” 2011). The risk of breast cancer increases when there is a family history of breast cancer. . For example, a woman whose sister or mother has breast cancer is more likely to develop the disease herself because the genetic mutation is hereditary (Klugar & Park 2013). According to the American Cancer Society, 5 to 10 percent of all cancers are caused by inherited mutations. This means that some people are more likely to develop cancer than others because they were born with mutations in their genes. Middle of paper She wanted to save her own life and that was by having a double mastectomy . But before undergoing a double mastectomy, a woman should consider trying different cancer prevention measures and, if they do not have much effect, then resort to prophylactic surgery as a last option. If any of my family members find out that she is at increased risk of breast cancer, then I would recommend that she try the cancer drug tamoxifen first to see how much it reduces her risk. If there was not much reduction, then I would recommend prophylactic mastectomy, as it gradually reduces the risk of developing cancer. The National Cancer Institute states that prophylactic mastectomy reduces the risk of breast cancer by at least 95% in women who have an acquired mutation of the BCRA1 or BCRA2 gene and by 90% in women who have a family history of breast cancer. breast (“Surgery to reduce," 2013).