Searching for one's ancestors using DNA testing has become wildly popular, but local oncologists are not excited about using that same DNA sampling to screen people for cancer, News Radio 1200 WOAI reports.
The popular DNA testing company '23 and Me' is now selling an FDA approved test that looks for specific genes which are connected with colo-rectal cancer.
Dr. Steven Kalter, an oncologist at San Antonio's START Center, says early testing is always good, but he has concerns about it being done by non medical organizations.
"I think these are important and potentially useful, but I'm concerned about too much dependence on this kind of testing, which is not really getting at the heart of the matter," Dr. Kalter said.
He says colonoscopies, for example, are simple tests that can not just determine whether you are genetically at risk for cancer, but whether early stages of the cancer are in your body, and can catch it at a stage when it can be treated.
"Colonoscopy is really the best way to screen someone for polyps or for cancer," he said. "It is colonoscopy that will tell us where we stand."
Between the mid 1980s and 2013, rates of colon cancer increased for people in their 20s and 30s by one to two percent a year, due largely to lifestyle factors, like obesity, lack of exercise, and not enough fiber in diets.
The Dr. Kalter says if somebody is going to get a diagnosis that they are genetically at risk for cancer, it is better that it take place in a medical setting.
"I'm very skeptical about people becoming very nervous about the results of the test, or over relying on this test, and not really talking with their physician about appropriate screening," he said.