BRCA 1 & 2 Gene Testing: What Does A Positive Test Mean And Should You Get Tested?
Posted Feb 01 2014 9:11am
The BRCA 1 and 2 gene mutations, and a handful of other (rarer) gene mutations, account for about 10% of all breast cancer cases. The abnormal genes affect about 1 in 400 people and can be inherited from either or both parents.
BRCA gene mutations increase the lifetime risk of breast cancer in women to between 50 and 87% (depending on the study). The lifetime risk of breast cancer in the general population is about 12%.
Due to the publicity BRCA has received in the media lately, most people think it only affects women. That's not true. Men can be affected too. Men carrying an abnormal BRCA gene have a 5-10% risk of getting breast cancer at some point in their lives. Unaffected men only have a 0.1% lifetime risk.
Families carrying the abnormal genes also have more than breast cancer to worry about. BRCA mutations significantly increase the risk of several other types of cancer in the family including ovarian, fallopian tube, peritoneal, pancreatic, colon, prostate and melanoma.
Anyone who has a strong family history of breast cancer should consider having a BRCA test. Those who are also of Ashkenazi Jewish descent are at particularly high risk of being affected; Ashkenazi Jews have a much higher prevalence of the BRCA1 and 2 mutations than the general population (1 in 40).
It's also important to consider the implications of a positive test before actually having it. What would you do if you found out you're affected? How would it affect your kids? The rest of your family? I strongly recommend genetic counseling before having any genetic test. Only then can you truly understand the implications of the test and what a positive result could mean for you and your family.