Oscar-winning actress Angelina Jolie announced on Tuesday that she had a preventative mastectomy after learning she had a gene that significantly raised her risk of breast cancer. Here's a crash course in the procedure Jolie had and why. Q: What kind of surgery did Jolie have? A: Jolie had a preventative double mastectomy, meaning she chose to have both her breasts removed even though she had not been diagnosed with cancer. Q: Why did she have the mastectomies?
A: Jolie says that she has a “faulty” version of the BRCA1 gene that means she has an 87 percent chance of getting breast cancer. By having both breasts removed preventatively, she said her breast cancer risk drops to 5 percent. Q: How many women have this faulty gene? A: Only a small percentage of women have this same faulty gene, or a similar mutated version of a related gene, BRCA 2. These mutations are most commonly found in women of Eastern European Jewish descent; one study found 2.3 percent of women in that group had the mutations — about five times higher than in the general population. Other ethnic groups, including the Norwegian, Dutch and Icelandic people, also have slightly higher rates of these mutations. Q: How do these genes increase a woman's risk of breast cancer? A: The average woman has a 12 percent risk of developing breast cancer sometime during her life. In comparison, women who have inherited a faulty version of a breast cancer gene are about five times more likely to get breast cancer. In the U.S., about 5 to 10 percent of breast cancers are thought to be linked to harmful versions of the BRCA1 and BRCA2 genes. Q: How can women find out if they have these gene mutations? A: A genetic test using a blood test can usually detect these genes. In the U.S., there are no standard guidelines recommending women for BRCA1 or BRCA2 genetic testing. The tests usually cost at least several hundred dollars.