The Food and Drug Administration (FDA) has allowed a genetic testing company, 23andMe, to sell direct-to-consumer genetic tests for finding out the risk of developing ten diseases, which include Parkinson’s disease, late-onset Alzheimer’s disease, celiac disease, factor XI deficiency and other serious conditions.

"Consumers can now have direct access to certain genetic risk information," said Dr. Jeffrey Shuren, director of the FDA's Center for Devices and Radiological Health, which approves these kinds of tests.

"But it is important that people understand that genetic risk is just one piece of the bigger puzzle. It does not mean they will or won't ultimately develop a disease."

Home DNA tests for 10 diseases

“The diseases were actually chosen because those were some of the reports consumers most requested from 23andMe,” said Kathy Hibbs, 23andMe’s chief regulatory officer. The company, based in California, has been providing reports of genetic ancestry and general health information to customers.

Consumers are able to request for the genetic tests and mail their saliva samples to the company in a tube for DNA test. The report can later be viewed online in six to eight weeks time. In addition to disease risk analysis, customers will also receive educational information and a cautionary note that reminds customers it does not indicate the developing of a disease.

For instance, ApoE4 is a gene variant that indicates risk for Alzheimer’s disease. A copy of this gene marks a threefold increased risk whereas two ApoE4 genes have a 15-fold increased risk. As for Parkinson’s disease, LRRK2 and GBA increase the risk by 25% and fourfold, respectively.

“This is an important moment for people who want to know their genetic health risks and be more proactive about their health,” said Anne Wojcicki, 23andMe CEO and cofounder.

“The difference between then and now is that we now have authorisation to tell you about your personal risk,” she added. The FDA also plans to issue a new exemption for other companies to market similar tests.

Different voices on the implications

Despite the convenience and opportunity for earlier diagnoses, the FDA’s approval concerned some physicians and researchers because it will disclose weighty information about genetic risk without counselling from a healthcare professional. Rudolph Tanzi, a neurology professor at Harvard Medical School, said consumers would “for sure” need genetic counseling along with the test results.

"Even physicians have a difficult time knowing how to interpret genetic test risk information. So this decision may wind up frightening as many people about genetic risk as it does empower them," New York University bioethicist, Art Caplan, commented.

To address the concerns, Hibbs stressed that the company had conducted studies to ensure Americans can access and understand the product in a safe and effective way. The FDA also said it had reviewed the tests through a new process.

While researchers believe genetic tests will not provide 100% accuracy, the Personalised Medicine Coalition welcomed the FDA’s move. Its president, Edward Abrahams, suggested that the genetic tests may “help inform patients’ behaviours and medical decisions.”

Meanwhile, John Lehr, CEO of the Parkinson’s Foundation said, “A datapoint without interpretation is not helpful.” He explained that when it comes to Parkinson’s, even if one’s genetics indicate a heightened possibility of the condition, the risk is still comparatively small, as age remains as the main risk factor.

Nevertheless, Dr. Gail J. Jarvik , head of the division of medical genetics at the University of Washington, remarked that nothing is easy in this new world of direct-to-consumers genetics. She said, “that can be a challenging concept to communicate.” MIMS

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