The famous Hollywood star––Angelina Jolie published an article in the New York Times on May 14, 2013, revealing that she herself had undergone a preventive mastectomy.
Jolie's mother fought breast cancer for nearly a decade and died at the age of 56; her aunt died at the age of 61 of breast cancer; and her grandmother also died of cancer.
After gene detection, doctors discovered the mutation of Jolie's BRCA1 gene is present, which could sharply boost the Jolie's risk of developing breast and ovarian cancer. On doctors' suggestion, Jolie accepted the preventive mastectomy which steeply reduced her risk of developing cancer to 5%. And afterwards in 2015, Jolie accepted preventative laparoscopic bilateral salpingo-oophorectomy, reducing her risk of developing the hereditary ovarian cancer to the lowest level.
Scientific studies discovered that BRCA1 and BRCA2 gene are two important tumor suppressor genes which can repair the damaged DNA. That the mutation occurs in BRCA1/BRCA2 may very likely cause the mutation in other functional genes not to be repaired, lead to functional gene deficiency, and thus induce a series of cancers, among which the mainly two cancers are the hereditary breast cancer and ovarian cancer. The risk of developing breast cancer in BRCA1/BRCA2 mutation carriers will be largely elevated, with an earlier onset age of this cancer.
As showed in the figure, the probability of breast cancer in the people carrying the BRCA gene mutation is far higher than common people.