Is it useful to know or not know if I am at risk of a particular disease? I’m interested to find out what others think about these types of DNA tests.
This is a very subjective opinion. It really depends on what type of person you are so it’s quite hard to give a clear answer. What I can say is that it’s not clear exactly what you should or shouldn’t do once you get your results. It’s hard to say with absolute certainty what are the most effective ways to prevent breast or ovarian cancer. Removing the breasts and ovaries to lower cancer risk does not mean you will not have any breast- and ovary-related cell left in your body. So even though surgery lowers your risk dramatically, it still does not entirely eliminate the risk. More so, normal test results don’t guarantee healthy genes. For example, in some families, many women have had breast cancer, yet they all test normal for the known breast cancer mutation.
Most companies, including 23andMe, analyse short pieces of DNA for genetic variation known as single nucleotide variations (SNPs) associated with specific diseases. Most of the tests have limitations and can be hard to interpret without a doctor or genetic counsellor. In the case of breast cancer, these only test for three mutations in two genes known as BRCA1 and BRCA2. Women could still have one of the thousands of other mutations that increase the risk, or be at risk for other, non-genetic reasons. My concern is that if you’re a woman and your DNA results indicate you’re free of the risky mutation, you may think it’s OK not to visit your doctor or get regular mammograms or even undergo more through genetic testing.
Personally, I would rather not know if I would have a predisposition to a specific disease. I have enough stress in my life already so having to deal with an oncoming disease or with the thought that this genetic mutation will be passed down to my children is too much for me. What I can do is to be more aware of the lifestyle I live, exercise more, eat better and healthier and try to visit my doctor regularly.