The Food and Drug Administration is cracking down on a “dangerous” medical product, but it’s not a drug or a diet or a surgery.

It’s information.

On Nov. 22, the agency issued a warning letter to, a DNA analysis company.  For just $99, 23andMe will send you a little vial to collect your saliva. Once you’ve mailed it back, the will run a battery of genetic tests and provide you with information about your genetic history, relatives, ancestral origins and how your genes affect your health.

23andMe has been a fast-growing service, building attention through an aggressive television, radio and podcast marketing campaign. But you won’t be hearing the company talk about its services for at least a little while since, per the FDA letter, “23andMe must immediately discontinue marketing the [personal genome service] until such time as it receives FDA marketing authorization for the device.”

The company’s PGS doesn’t sequence your entire genome. It looks instead at specific regions of your genes that tend to vary across the population and have known consequences.  Once they’ve figured out which versions of these single-nucleotide polymorphisms you’ve got, they tell you what the academic research has found.  Maybe one of your mutations is associated with Himalayan ancestry (a fun fact about your family) or a higher sensitivity to blood-thinners like Warfarin (an important piece of data for your doctor).

The FDA is worried about the latter kind of data.  In their letter, the regulators write:

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.

In other words, learning about your risk for breast cancer through an imperfect test might lead you to get unnecessary surgery or ignore warning signs.

Mammograms are still legal, by the way.

Banning 23andMe because it gives patients data they might misuse is roughly analogous to shutting down WebMD or Wikipedia.  While 23andMe can tell me that some sequences in my genes are associated with a greater risk of breast cancer, WebMD can tell me that my persistent cough is associated with a cold or pneumonia or lung cancer.  Either way, I won’t end up on chemo or under a surgeon’s knife without going through the usual medical gatekeepers.  I bring my suspicions to a doctor and the expert makes the final call about whether to alter my treatment.

If genetic assays for consumers are causing problems, it is not because they’re revealing perilous information about the patient, but because they’re exposing a gap in the way the medical establishment is prepared to use and explain genetic and statistical data.  That’s the ailment the FDA should be addressing.