When genetic tests are more misleading than helpful

  • This artwork by Donna Grethen relates to genetic testing becoming more affordable for those interested in finding out if they are predisposed to life-threatening illnesses.

Cutting edge companies often walk a tightrope between regulators trying to keep their technologies under control and marketers trying to push them out to consumers as fast as possible.

That's where a Silicon Valley company named 23andMe is today. The Mountain View firm has been hawking genetic tests for you to take at home. You spit into a receptacle and ship your saliva back to the company so it can analyze your DNA for a mere $99. Eventually you get a readout detailing your genetic susceptibility to hundreds of diseases.

At least, that used to be the case. At the end of November, regulators at the Food and Drug Administration instructed the firm to shut down its genetic analysis service, declaring — with plenty of justification — that the company's marketing claims were running well beyond what was valid, or legal. The service fell within the legal definition of a medical diagnostic device, the agency said, and demanded data demonstrating the tests' technical validity. It warned 23andMe to ratchet back its marketing claims for the service, which it said requires agency approval before it can be sold to consumers — "as FDA has explained to you on numerous occasions," the agency said.

The company will still send customers their raw genetic data and an analysis of what it says about their "ancestry," but it has stopped issuing disease-risk analyses until it gets right with the FDA. Customers who ordered their tests on or after the date of the FDA's warning letter, Nov. 22, can get a refund.

Personal genetic testing has been building toward a craze for some time, as evidence mounts that certain genes or mutations can affect individuals' health profiles. Consumer interest often spikes with news events: Anne Wojcicki, the founder and CEO of 23andMe, says inquiries poured into her office in May, after actress Angelina Jolie disclosed that she'd undergone a precautionary double mastectomy upon learning she carried a gene that predisposed her to breast cancer.

23andMe — the firm's name derives from the number of chromosome pairs in the human cell — has become the best-known company in the field for a couple of reasons. One is the unique pizazz of its corporate pedigree. It's backed by Google, whose co-founder Sergey Brin is Wojcicki's husband. (They separated earlier this year.) Another reason is its aggressive national advertising, for which it budgeted $5 million for 2013 alone. But that was before the FDA swooped down; the TV ads have been taken off the company's YouTube channel.

The problem with the service provided by 23andMe and its competitors — and the root of the FDA's concern — is that raw genetic information is very hard for a lay person to interpret. "The technology is just not ready for prime time," says David B. Agus, a University of Southern California cancer specialist who co-founded Navigenics to market professional genetic testing services.

Agus says test interpretation should be done by physicians or trained genetics counselors. "Medicine is lots of shades of gray, so you need discussion with someone who's trained in the field," he says. Agus says he has no financial interest in Life Technologies, which acquired Navigenics in 2012, though he sometimes offers the company unpaid advice.

The reports issued by 23andMe prior to the FDA letter typically included pages of qualifications of the genetic results for every health issue, followed by a broad disclaimer stating that the information "is intended for research and educational purposes only, and is not for diagnostic use." That unnerves medical experts, who think many customers will stop reading when they reach the headline figure about their risk of acquiring a disease or condition compared with that of the general population. The firm's marketing can lead customers to assume they actually are getting a diagnosis.

"Any reasonable interpretation would assume this is news you can use, until you get to the disclaimer," says David Hunter of the Harvard School of Public Health, a critic of direct-to-consumer marketing of genetic testing. "The problem is we are notoriously poor at estimating risk and communicating relative and absolute risk." That may be especially true in genetics, where the effect of a single gene or mutation can be vanishingly incremental but the revelation that you carry it can strike like the tolling of a bell.

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