On March 6, the Food and Drug Administration gave the go ahead to genetic testing company 23andMe to offer consumers a screening kit for three breast cancer mutations. This means consumers could get results without involving a doctor or genetic counselor.
J. Leonard Lichtenfeld, MD, MACP, our deputy chief medical officer, comments on this in 'Dr. Len's Blog.' Bottom line: the limitations of the test make this anything but straightforward.
The home test - a collection of saliva - will check for three specific mutations in the BRCA gene, which—if present—represent a signal that a man or woman is at an increased risk of certain cancers. For men, increased prostate cancer risk and the ability to pass the gene on to their children are the most important implications. For women, increased risk of breast and ovarian cancer top the list, in addition to the possibility they, too, could pass the gene to their offspring.
Dr. Len says "if the test comes back positive, then you have one of the three “founder” mutations tested. (A founder mutation is a genetic change that has been passed down from generation to generation, and is most common in Jewish folks of eastern European or Ashkenazi decent). You can then go to your health professional and find out what your next steps should be to confirm the test, and what you can do to reduce your risk of cancer.
"However, it is not so simple," says Dr. Len. "You see, these are only three of what are probably thousands of mutations that can occur in the BRCA genes. And most of the BRCA abnormalities found in the United States population are NOT founder mutations. So, there is a high likelihood that you could have a strong family history of breast and/or ovarian cancer, get a negative test, and yet still harbor a mutation that could substantially increase your risk of cancer, especially breast and ovarian cancer in women.
"In short, you might be led to think you are “off the hook,” when the hook is still very much intact."
Read Dr. Len's full blog entry.
And, here is a New York Times article about the FDA approval.