Fast Company has a profile on 23andMe, the de facto public face of genetic testing, that's worth a read just for the look at the underpinnings of the science. But there's a moment in there that teases out the gut punch that can come from that knowledge, and that's closely related to how genetic testing in sports might look.
The writer, Elizabeth Murphy, had herself and her adopted daughter tested by 23andMe. The results bring home a reason a lot of people have for not getting tested, and for being less informed about their genetics:
And there it is, screaming out at me from my computer screen. My daughter, who is learning to read and tie her shoes, has two copies of the APOE-4 variant, the strongest genetic risk factor for Alzheimer's. According to her 23andMe results, she has a 55% chance of contracting the disease between the ages of 65 and 79. My husband, who is out of town on business, texts that he will call me at 8:30. "Everything okay?" he adds. "All good," I write back, "except our daughter is going to get Alzheimer's."
There are three main variants of the APOE gene: ... E4 is trouble; not only does it seem to dramatically increase the likelihood of a person developing Alzheimer's, but it also increases her chances of doing so at an earlier age. Roughly 22% of the population has one copy of e4; about 3% have two copies. My daughter's genes place her in that dreaded narrow sliver. "A vanishingly small number of [23andMe's] results fall into that category where you can say, 'Oh, all right, I'm going to get this disease or I'm not,' " says UNC's Evans. "The APOE-4 approaches that." Meanwhile, my results show that I have a copy of the protective e2 gene, locked impotently within each of my cells, where it can do my daughter zero good. My family has found out, as Evans would say, something really scary.
ApoE4, in addition to its ties to Alzheimer's discussed here, is also believed to impair recovery from brain injuries, and possibly make you more susceptible to them in the first place. There's been some badgering for athletes (and their parents) to at least be made aware of these possibilities, and possibly get tested for them, before playing a sport like football. Of course, for some athletes, that would take this traumatic finding—a claimed 55 percent chance of contracting Alzheimer's Disease—and layer on top of it the fact that if you play football, possibly well enough to go pro and change your life, you're walking your brain right off a cliff.
And that's going to be heartbreaking in some cases—but also necessary. Not necessary to any one person, specifically; there are perfectly valid reasons that a person wouldn't want to know about conditions that they have no control over, even if it means forgoing additional information about their health and career. But for the larger population—whether it's humanity in general or just the people playing a specific sport—the necessity of getting many people, including those with uncommon traits we don't totally understand yet, is obvious:
"People like your daughter are invisible to pharma," Emily Drabant, a former Stanford neuroscientist who's now 23andMe's manager of business development and alliances, explains later. "The way these research studies are typically done is they bring in people with Alzheimer's, give them a drug, and see what happens. Do they get better? Like a number of other brain diseases, the Alzheimer's process starts before you start having symptoms, so the changes in your brain are happening before you are actually manifesting dementia. Most of pharma's trials have failed, and the key takeaway is a) they may have been targeting the wrong molecule and b) they were intervening too late. So now what pharma wants to do is new trials in people who are at high risk, who are like 60 and e4 carriers. But what's hard for pharma is this: How do you find people who don't yet have Alzheimer's and aren't sick? They're not going to a doctor. Well, we have 65,000 people in 23andMe who are e4 carriers, and we have 6,000 people in 23andMe who have the same genotype as your daughter's."
The broad allure of the testing is obvious. As founder Anne Wojcicki says, "There's a whole group of people who are 100-plus and have no disease. Why?" But there's something here for sports, too, and sports leagues (or governing bodies) in particular. This is the longitudinal data that sports lack right now, for issues like brain trauma and CTE, but maybe also for things as simple as "Is there a genetic marker for durable ligaments? For fragile ones?" Or anything else, really. As it is, when things work out for the best, like with Jeff Green's heart condition being discovered during a physical after he was traded to Boston, it's taken as providence.
The other side of this, of course, is the unrelenting shitheadedness of professional sports teams. It would take literally zero time for management to start voiding contracts because players withheld genetic information that it was probably well within their rights to withhold. Maybe those are just impossible waters to navigate. But if someone can figure it out, we'll stand to have a lot better understanding of athletes' health, and athletes in general.