As stated by Heidi Chial (2006), proto-oncogenes encode proteins that stimulate cell division and differentiation and perform a specific function. Proto-oncogenic processes are essential for human health and the maintenance of organs and tissues (Chial, 2006). On the other hand, tumor suppressor genes slow cell division, correct DNA errors, and allow cells to die – this simply prevents cells from becoming cancerous (American Cancer Society [ACS], 2011). Mutations can occur in these genes, that is, an alteration in the DNA sequence that changes their own function and can cause health problems. Proto-oncogenes for example, when mutated, activate the oncogene (modified version), which causes acceleration and increase in cell division and quickly goes out of control and leads to cancer (ACS, 2011). When mutations occur in tumor suppressor genes, as Katherine M. Hyland (nd) puts it, they disable the ability to correct DNA errors and cancer also develops. The National Cancer Institute (2014) states that the initial role of the BRCA gene is to produce proteins that contribute to breast development, repair damaged DNA, and prevent rapid cell growth. For this same reason, the BRCA1 and BRCA2 genes belong to the category of tumor suppressor genes (Kluger and Park, 2013). Mutations in these genes are linked to breast cancer because most BRCA genes are found in breast tissue, as stated by Kluger and Park (2013), and when mutations occur, accumulation of cancer cells begins and breast cancer grows.Barbou S. Warren and Carol Devine (2003) stated that not all forms of breast cancer are hereditary; These are either familial cancers (hereditary from parents) or sporadic cancers (no family history of cancer). According to one figure......middle of article......a double mastectomy was a logical alternative. The double mastectomy reduced her cancer risk from 87% to just 5% (Kluger and Park, 2013). In Angelina's case, the operation also increased her lifespan based on her mother's history, also stated by Kluger and Parker (2013), as her mother died of ovarian cancer at 56 years, a cancer also influenced by the BRCA gene mutation. If a family member were diagnosed with an increased risk of breast cancer, I would simply recommend that they have a double mastectomy. I would not want anyone in my family to be screened at least once a year and during this year off for developing cancer. Like Angelina Jolie, her preventive double mastectomy significantly reduced her risk of cancer and increased her lifespan (Kluger and Park 2013). A member of my family may have the same opportunity to expand their life and reduce cancer..