Could CRISPR Genetically Tailor Athletes? It’s a Nice Idea.
The new genetic tool has the potential to increase resistance to muscular injury or stress fractures—even produce stronger, faster athletes—but it's a puzzle that could take decades to solve

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Our ability to edit genetic material took a huge leap forward in 2012 with the development of a gene editing tool called CRISPR (which stands for 'clustered regularly-interspaced short palindromic repeats'.) Cheap and relatively easy to use, CRISPR, as CBS News explains, lets “scientists cut and paste specific portions of DNA, offering a path to new treatments or cures for genetic diseases.”
Labs across the world are already using what many have been calling a Nobel Prize-worthy discovery, and Science magazine just voted CRISPR its 2015 “Breakthrough of the Year.” It’s so quickly advancing the ability to alter genes that it even prompted an International Summit on Human Gene Editing in Washington, D.C., earlier this month, where the world’s leading geneticists debated the ethics behind its potential uses.
But while gene editing technology has been evolving faster than anyone could’ve imagined just a few years ago, the days when we’ll be able to make ourselves innately faster, stronger, and more resilient, says Stanford genetics professor Dr. Stuart Kim, are still far enough off, they might as well be the stuff of science-fiction.
“It’s only barely possible to cure a disease right now. Not to make people better, but to cure a genetic disease, and that’s just starting.”
“It’s only barely possible to cure a disease right now,” says Kim, who runs his own eponymous lab at Stanford, focused on the genetics of aging. “Not to make people better, but to cure a genetic disease, and that’s just starting.” Current research is largely focused on single-gene disorders, or illnesses thought to be caused by a single mutated gene, like Huntington’s, or SCID aka Bubble Boy disease. It’s easier for scientists to home in on the fix, and to expect a positive outcome once the problem gene is repaired.
On the other hand, treatments that would interest healthy athletes by increasing resistance to muscular injury or stress fractures, for example, will likely involve multiple genes, and figuring out how altering one might affect the behavior of others is a puzzle that could take decades to put together. “There is a need to understand the risks,” the gene editing summit’s organizing committee concluded, including the possibility that the editing technique itself could be inaccurate, sometimes missing its intended target. Or that altering one gene could cause a life-threatening chain reaction.
But while the invention of an injury-proofing serum might be a fantasy for now, using genes to optimize athleticism is not. Services like 23andMe can now map parts of your genome for a few hundred dollars, and scholars like Dr. Kim and his colleagues are starting to make sense of some of that information—enough to provide actionable advice to athletes.
For example, Kim’s lab has been conducting DNA studies of 900 Stanford varsity athletes in 30 different sports. “I want to look at their DNA and at their injuries and see if we can see the difference between guys who get injured and guys who didn’t get injured and thereby make a DNA diagnostic that you could use in the pre-season,” Kim says.
Scientists have already linked certain genes to a higher risk of stress fracture, Kim points out. That knowledge might encourage a runner, for example, to incorporate more cross-training into his or her program.
Using genetic information to guide training and avoid injury isn’t the same as injecting a magic bone-strengthening elixir, but it’s a start—one that should thrill data-driven athletes. “Looking at who you are personally and trying to tune your training,” Kim says, “that’s pretty realistic.”