Sports genetics: Kenyans, Ethiopians… and Tibetans


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A must-read article for anyone interested in the interplay of sports and genetics (and for anyone who’s adamantly convinced that Kenyans and Ethiopians dominate distance running because they’re born to run), by Sports Illustrated’s David Epstein. The article is too good and too packed with info to summarize with a few pithy quotes — the fact is, it’s a very complicated area. But the overall message plays down the roles of genes:

Pitsiladis selected 24 gene variants most often associated with sprinting or endurance prowess and looked for them in the genomes of four men who have held the world record in the 100-meter dash and five who have held the world record in the marathon. What he saw was that based on those genes, the world-beaters are not genetic outliers at all. Pitsiladis analyzed the DNA of some of his graduate students for comparison and found that “a student of mine has a better rating for sprinting than the likes of an Asafa Powell or Usain Bolt.”


A decade ago, when Pitsiladis began to study elite athletes, his medical students would ask why East Africans dominate distance running, to which he would reflexively respond that their secret is in their genes. “But after 10 years of work,” he says, “I have to say that this is a socioeconomic phenomenon we’re looking at.”

Having read Epstein’s article, I was interested then notice this press release from the University of Utah this morning:

Researchers have long wondered why the people of the Tibetan Highlands can live at elevations that cause some humans to become life-threateningly ill – and a new study answers that mystery, in part, by showing that through thousands of years of natural selection, those hardy inhabitants of south-central Asia evolved 10 unique oxygen-processing genes that help them live in higher climes.

Of course, the Tibetans live at much higher elevation than Kenyans and Ethiopians do (and they don’t seem to be particularly good at running). Still, the study seems to suggest that many generations of living at altitude does produce changes that show up in your DNA. It would be interesting to find out whether East African populations living at altitude show any particular patterns for these 10 genes related to oxygen processing.

One Reply to “Sports genetics: Kenyans, Ethiopians… and Tibetans”

  1. Here’s a quote that hits home with me.

    But one interesting difference was that the high runners’ brains were larger. “Presumably, the centers of the brain that deal with motivation and reward have gotten larger,” Garland says. His team plied mice with Ritalin, a stimulant that alters dopamine levels. Once doped, the normal mice, apparently gleaning a greater sensation of pleasure from activity, suddenly ran more. But the doped long runners did not. Whatever Ritalin does in the brains of normal mice is already happening in the brains of the high runners. They are running junkies.

    Since I started running consistently about 10 years ago, I’ve been on a few emotional roller coasters – something that I had not experienced before. When I stop running, I usually end up going into a depression. I’m not talking about feeling bad or having a bad day, I actually have self destructive thoughts and behaviour and I feel like doing absolutely nothing.

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