23andMe is providing data that physicians don’t know how to manage

The FDA has ordered 23andMe, a company that does direct to consumer genomic testing, to halt sales. I can’t speak on the accuracy of the results with 23andMe, I think that’s what the FDA is interested in. And this isn’t a post about transparency, because I think everyone should have access to their medical data. This also isn’t a post about genomics being bad. On the contrary, I believe we will come to a point in time where we can run genetic profiles and predict who is more likely to be a medication responder or do well with a specific surgery. So I applaud more research in this area. I maintain that there are no medical miracles, just genetics we have yet to understand. One day we won’t shrug our shoulders when one person survives a cancer that kills 90% of people, we’ll have a genetic answer.

I have a very narrow experience with 23andme. I have only encountered one clinic scenario, but it’s happened a few times and it is a good example of what happens when you have answers to a question that not only did no one ask, but that no one was going to ask. And of course, it’s a lesson in what do you do when you have this kind of information and I think it encapsulates some of the concerns held by the FDA and by people who know way more about genetic testing than I do.

Say you are a young woman and you get tested via 23andMe and you are told based on your genetic profile that you carry a genetic mutation that may increase your risk for blood clots. You have no personal or family history of blood clots so you had no clinical indication for testing, yet now you have these results. What next?

Certain genetic mutations do confer an increased risk of abnormal clotting, some significantly, although not everyone with the mutation that you tested positive for will have a blood clot. In fact, most won’t and so universal screening isn’t recommended. Many investigators have looked at this specific mutation and wondered, should we screen women with no history (personal or family) for this mutation? After all, women are more likely to take a medication with estrogen (birth control pills) and they get pregnant, both of which increase the risk of blood clotting, which is potentially fatal. However, after a lot of studiesobsessive reviews, and hashing it out at meetings the experts seem to agree. Mass screening, testing women with no family or personal history, for this specific mutation is likely to cause more harm than good, so we don’t recommend it.

But now you have the result and you tested positive. Now you have the result that if you act upon it might cause more harm than good. You just don’t know. What do you do? Do you go with the belief that your risk might be higher? Do you ignore the results? It’s a conundrum.

If you’re a young woman and you go with the results that means not taking the birth control pill with estrogen. Maybe that’s not such a biggie, after all there are IUDs. But what if for some reason you don’t want an IUD? What if you get pregnant because you choose a non-IUD form of contraception with a higher failure rate than the pill?

And then what do you do in pregnancy? Do you take blood thinners during pregnancy or just after delivery or do we give them to you at all? What if you get blood thinners because your doctor is worried that if you get a blood clot he or she will get sued because some women, regardless of genetics, will have a blood clot. What if you get blood thinners and have a catastrophic bleed during your delivery and lose your uterus or even worse, die? If you truly had an increased risk, then studies tell us that with blood thinners the benefits outweigh the risks, but what if you didn’t really have an increased risk to begin with? Then you have assumed all the risks of blood thinners with no potential benefit.

So the problem that I have encountered, albeit in a very narrow spectrum, is that you can get test results that your medical providers just don’t know how to manage. The recommendations are not to do mass screening of young reproductive age women for this specific mutation because for the majority of women the results turn out to be the equivalent of  a false positive.

I was always taught that I shouldn’t order a test if I have no idea what to do with the result. If mass screening for this genetic risk of clotting were considered standard of care we’d be doing it. Especially in pregnancy, which is a time of mass screening.

Genetics has a lot to offer, but it’s also important that people understand the limitations and with our current body of knowledge the results can sometimes make medical care more confusing. That is of course why genetic counseling before these tests is so very valuable (although how you can inform someone about their entire genomic risk before you test, I have no idea).

23andMe has halted sales temporarily, but at some point this testing will start up again and somehow we are going to have to figure out what to do with this kind of raw data, because until someone actually knows what to do with the results it’s just that, data not information. And there’s a difference.

Jennifer Gunter is an obstetrician-gynecologist and author of The Preemie Primer. She blogs at her self-titled site, Dr. Jen Gunter.

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