A BRCA mutation is an irregularity in the breast cancer (BRCA) gene which can make someone more susceptible to developing breast cancer. BRCA mutations do not guarantee that someone will develop breast cancer, but they make cancer much more likely, and a mutation can be an indicator that certain preventative steps should be taken to reduce the risk and to identify cancer early, if it does emerge. Genetic testing can be used to determine whether or not a defect is present on this gene.
Two genes have been associated with the development of breast cancer: BRCA1 and BRCA2. Both are in a class of genes known as tumor suppressors, and defects on these genes appear to make people less capable of suppressing tumors on their own. In the case of BRCA1 and BRCA2, the specific mutation makes women and men vulnerable to developing breast cancer, although breast cancer in women is far more common.
BRCA1 is found on chromosome 17, while BRCA2 is on chromosome 13. In genetic testing for the presence of a BRCA mutation, a small sample of blood is taken and analyzed in a laboratory to look for the mutation. Genetic testing for other mutations is also available, with the cost usually increasing with the number of tests which need to be run.
BRCA mutation testing is not recommended for everyone, because it can be very expensive. Women who have a family history of breast cancer, especially in their mothers, or a family history of BRCA mutation, should get a screening for BRCA mutation. A family history of cancer in general, especially cancer with early onset, is also an indicator that a screening test might be advisable. This mutation can also appear spontaneously, and some doctors recommend BRCA testing after women are diagnosed with breast cancer, to determine whether or not a BRCA mutation was involved.
Two things are involved in the testing: the test and analysis, and genetic counseling. Genetic testing is often accompanied with a counseling session to discuss the ramifications of the test. In a BRCA test, for example, the presence of a mutation does not indicate that the subject has cancer, or even that cancer will develop, it just suggests that there is an increased likelihood, in which case frequent screenings for breast cancer or screenings which start at an earlier age than usual may be recommended. In extreme cases, women may opt for preventative mastectomies or medication in an attempt to prevent the onset of breast cancer.