More and more people are deciding to learn whether or not they have an abnormality in what have come to be known as the “breast cancer genes,” BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two). Women who inherit a mutation, or abnormal change, in either of these genes — from their mothers or their fathers — have a much higher-than-average risk of developing breast cancer and ovarian cancer. Men with these mutations have an increased risk of breast cancer, especially if the BRCA2 gene is affected, and possibly of prostate cancer. Many inherited cases of breast cancer have been associated with these two genes.
The function of the BRCA genes is to keep breast cells growing normally and prevent any cancer cell growth. But when these genes contain the mutations that are passed from generation to generation, they do not function normally and breast cancer risk increases. Abnormal BRCA1 and BRCA2 genes may account for up to 10% of all breast cancers, or 1 out of every 10 cases.
Remember that most people who develop breast cancer have no family history of the disease. However, when a strong family history of breast and/or ovarian cancer is present, there may be reason to believe that a person has inherited a BRCA1 or BRCA2 mutation. Some people choose to undergo genetic testing to find out. A genetic test involves giving a blood sample that can be analyzed to pick up any abnormalities in these genes.
In this section, you can read more about the following topics related to genetic testing for BRCA1 and BRCA2 mutations:
- Learning About Your Family Background
- Deciding Who in the Family Should Get Tested
- Consent for the Gene Test
- Seeking Your Genetic Information: Pros and Cons
- Genetic Testing Facilities and Cost
- Getting Genetic Test Results
- What to Do if Your Genetic Test Results Are Negative
- What to Do if Your Genetic Test Results Are Positive
- What to Do if Your Genetic Test Results Are Uncertain
If you want to learn more about family-related risk and genetics, you can visit the Lower Your Risk section of this site.
Researchers have discovered, and are continuing to discover, other gene abnormalities that are less common than BRCA1 and BRCA2 but also can raise breast cancer risk. Testing for these abnormalities is not done routinely, but it may be considered on the basis of your family history and personal situation. You can work with your doctor to decide whether testing for gene abnormalities besides BRCA1 and BRCA2 is warranted.
The medical experts for Genetic Testing are:
- Rachael Brandt, M.S., C.G.C., genetic counselor, Main Line Health Cancer Center, Philadelphia, PA
- Generosa Grana, M.D., F.A.C.P., breast cancer genetics specialist, Cooper Hospital/University Medical Center, Camden, NJ
- Marisa C. Weiss, M.D., breast radiation oncologist, Lankenau Hospital, Thomas Jefferson University Health System, Philadelphia, PA
These experts are members of the Breastcancer.org Professional Advisory Board, which includes more than 60 medical experts in breast cancer-related fields.
Simply having a proven gene abnormality does not necessarily mean that a woman will develop breast cancer, or that her cancer will be any worse than cancer that does not stem from an inherited genetic flaw.