Should I Get Genetically Tested for AMD?
September 22, 2011 - More genetic tests are becoming available everyday for
a wide range of diseases, including age-related
macular degeneration (AMD), the leading cause of blindness in people 50
years of age and older. As our Baby Boomer population ages, more people are
becoming at risk of losing their vision to the disease. As a result, people are
interested in determining the likelihood that they will be affected. But can a
genetic test help determine a person’s risk for AMD?
AMD is a complex condition. Scientists estimate that genetics may contribute
anywhere from 40 to 70 percent to one’s risk of developing the disease with
lifestyle and environmental factors contributing to the rest of the risk.
However, some people never develop it, even though both parents have it. Some
people develop AMD even though neither parent has it.
The best way to determine if one is at risk of developing vision loss from AMD is to have someone who is an expert at evaluating the retina perform an exam and determine if there are signs of an early stage of AMD, specifically large yellow deposits in the center of the retina called drusen. The amount and type of drusen will tell your doctor a lot about your potential for AMD-related vision loss.
Regular eye exams are critical to determining your risk for AMD and other eye diseases such as glaucoma and cataracts. The frequency of exams will be determined by your eye doctor, who will base his or her recommendations on a baseline exam as well as your family and medical history.
Genetic testing for AMD is still an active area of research. Most experts agree that information from such tests does not currently have a role in the management of patients, because the tests do not determine precisely whether an individual will develop macular degeneration.
While some companies offer consumers genetic testing for the known gene mutations found in individuals with macular degeneration, many people identified by these tests at highest risk will not get AMD. As mentioned, having an ophthalmologist look at your eyes periodically for drusen is a much more accurate predictor of vision-threatening disease.
The best thing you can do to reduce your risk for developing AMD is to not smoke. Cigarettes can cause a lot of problems, and an increased risk of developing vision loss from AMD is yet another reason among many to stop smoking. Some studies have shown that eating a diet rich in colorful fruits and vegetables can lessen your AMD risk. It’s also important to protect your eyes from bright sunlight with sunglasses that block UVA and UVB rays.
The Foundation Fighting Blindness strongly urges anyone who does get a genetic test for AMD or any retinal disease to consult with a trained genetic counselor or a physician who understands the specifics of the genetics of eye diseases and what the test results mean.