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The Food and Drug Administration has ordered DNA testing company 23andMe to stop marketing its over-the-counter genetic test, saying it’s being sold illegally to diagnose diseases, and with no proof it actually works.



The heavily marketed test includes a kit for sampling saliva, and the company promises to offer specific health advice. “Based on your DNA, we’ll provide specific health recommendations for you,” the company says on its website. "Get personalized recommendations."

In an unusually scathing letter dated Friday, the FDA says it’s been trying to work with the company to get some sort of evidence that the test can do that with any accuracy.

“The Food and Drug Administration (FDA) is sending you this letter because you are marketing the 23andMe Saliva Collection Kit and Personal Genome Service (PGS) without marketing clearance or approval in violation of the Federal Food, Drug and Cosmetic Act,” the agency says in a letter addressed to Ann Wojcicki, CEO of 23andMe.

“Therefore, 23andMe must immediately discontinue marketing the PGS until such time as it receives FDA marketing authorization for the device.”

California-based 23andMe says it has tested the DNA of half a million customers.

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"We have received the warning letter from the Food and Drug Administration," the company said in a statement. "We recognize that we have not met the FDA's expectations regarding timeline and communication regarding our submission. Our relationship with the FDA is extremely important to us and we are committed to fully engaging with them to address their concerns."

The agency says the company is making worrisome promises, including assertions that it can tell people their risk of breast cancer and sensitivity to the blood-thinning drug warfarin.

“For instance, if the BRCA-related risk assessment for breast or ovarian cancer reports a false positive, it could lead a patient to undergo prophylactic surgery, chemoprevention, intensive screening, or other morbidity-inducing actions, while a false negative could result in a failure to recognize an actual risk that may exist,” FDA says in the letter.

The FDA details just how hard staffers have tried to work with the company to sort out these issues, including more than 14 face-to-face meetings and teleconferences and "hundreds of email exchanges" in which the agency gave the company detailed instruction on what to do.

But the company hasn’t provided any evidence that it has, in fact, tested the accuracy of these various genetic probes. “Thus, months after you submitted your 510(k)s and more than five years after you began marketing, you still had not completed some of the studies and had not even started other studies necessary to support a marketing submission for the PGS. It is now nine months later, and you have yet to provide FDA with any new information about these tests,” it says.

FDA’s been warning gene testing companies since 2010, when it told five of them, including 23andMe, that they needed approval. But 23andMe is currently the only company being told to stop marketing its test.

Experts worry the tests are based on flimsy data. "23andMe has been growing by leaps and bounds in terms of its marketing and promotional efforts," says Art Caplan, head of the Division of Medical Ethics at NYU Langone Medical Center and a frequent NBC News contributor. "They have been the most aggressive in marketing."

Despite these worries, the tests have received extensive media coverage.

Caplan says the average person cannot learn much from genetic tests yet. "Say you have a gene that increases risk. We don't know much about whether it will strike when you are 20 or when you are 90," Caplan says. "We do have a better indicator. it's called the bathroom scale."





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