The 23andMe Saliva Collection Kit and Personal Genome Service (PGS) has made plenty of headlines in recent months, thanks in part to its aggressive marketing campaign and very thorough media coverage. More than half a million customers have had their blood tested but the US Food and Drug Administration (FDA) says enough already. The federal agency governing medical devices has recently issued a warning letter to the product’s manufacturer demanding it to stop selling the tests immediately.

According to the FDA, the tests have not been thoroughly tested in accordance with government standards and no authorization to market the tests has been granted. Therefore, all sales made thus far are illegal.

Another FDA concern is that there is no proof the tests actually work as advertised, and no concrete evidence the tests can accurately diagnose or predict genetic diseases in spite of the company’s claims. Part of the marketing package includes the promise of providing specific, personalized health recommendations to individuals who return blood samples.

One concern of the FDA is that a misdiagnosis made by the company may compel an individual to undergo expensive and unnecessary tests or treatments based on a false reading of a customer’s DNA sample. The FDA warning letter cites the danger of a false positive test result for BRCA-related breast and ovarian cancers.

Another concern is that a failure to identify a genetic concern could lead to life-threatening complacency at a time when aggressive medical care is vital.

The FDA crackdown on gene testing companies began in 2010, when five such companies, including 23andMe, were notified that they were operating without FDA approval. Four of them stopped selling the gene tests but 23andME continued to market its collection kit and PGS.

More than a dozen meetings and teleconferences and hundreds of email exchanges followed but the 23andMe company is still operating outside the sanction of the government. The FDA has called for immediate discontinuance of sales.

Medical experts outside the realm of the FDA are concerned, too, about the flimsy data being used in these genetic assessments. One outspoken critic is Art Caplan, of New York University Langone Medical Center, where he is head of the Division of Medical Ethics. Caplan is also a frequent contributor to NBC News.

According to Caplan, identifying a gene that increases risk is not enough; merely identifying a gene doesn’t indicate when problems may arise - when a person is 20 years old, 90, or if ever.

Caplan promotes his own tried-and-true, low-tech recommendation for assessing one’s life-long health risks - the bathroom scale.

Source: “23andMe, Inc. 11/22/13 (letter).” Inspections, Compliance, Enforcement, and Criminal Investigations / US Food and Drug Administration. US Department of Health & Human Services. Nov 22, 2013. Web. Dec 3, 2013.