8,000-Year-Old Mutation Key to Human Life at High Altitudes

Medical Xpress, August 17, 2014

In an environment where others struggle to survive, Tibetans thrive in the thin air on the Tibetan Plateau, with an average elevation of 14,800 feet. A study led by University of Utah scientists is the first to find a genetic cause for the adaptation–a single DNA base pair change that dates back 8,000 years–and demonstrate how it contributes to the Tibetans’ ability to live in low oxygen conditions. The study appears online in the journal Nature Genetics on Aug. 17, 2014.

“These findings help us understand the unique aspects of Tibetan adaptation to high altitudes, and to better understand human evolution,” said Josef Prchal, M.D., senior author and University of Utah professor of internal medicine.

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First author Felipe Lorenzo, Ph.D., spent years combing through the Tibetans’ DNA, and unlocking secrets from a “GC-rich” region that is notoriously difficult to penetrate. His hard work was worth it, for the Tibetans’ DNA had a fascinating tale to tell. About 8,000 years ago, the gene EGLN1 changed by a single DNA base pair. Today, a relatively short time later on the scale of human history, 88% of Tibetans have the genetic variation, and it is virtually absent from closely related lowland Asians. The findings indicate the genetic variation endows its carriers with an advantage.

Prchal collaborated with experts throughout the world to determine what that advantage is. In those without the adaptation, low oxygen causes their blood to become thick with oxygen-carrying red blood cells–an attempt to feed starved tissues–which can cause long-term complications such as heart failure. The researchers found that the newly identified genetic variation protects Tibetans by decreasing the over-response to low oxygen.

These discoveries are but one chapter in a much larger story. The genetic adaptation likely causes other changes to the body that have yet to be understood. Plus, it is one of many as of yet unidentified genetic changes that collectively support life at high altitudes.

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  • IstvanIN

    We be all the same. This be rascist scienece.

    • propagandaoftruth

      Imagine…

      Humans are animals whose internal organs physically adapt to their environment.

      Except for their brains, which are in fact metaphysical gas clouds that float in our craniums and have nothing to do with our parents’ genetics.

      In Whites this metaphysical gas cloud is especially noxious, emanating wicked magical racist vapors which only some can detect. They inherit this from their evil fathers, of course.

      But worry not. Soon the metaphysical gas clouds of non-Whites will save the day.

  • Adolf Verloc

    Quite aside from its racial realist implications, I really enjoy reading about a lot of this science. Nicholas Wade has examined a lot of evidence about how natural selection has operated even within historic times.

    • propagandaoftruth

      You are engaging your metaphysical brain gas well sir. See above. Evolution has never stopped, has it? Evolution, devolution, brutal stuff that.

  • dd121

    How many base pairs need to change before blacks become fully human?

    • IstvanIN

      Too many.

  • Valmont

    This is fascinating, but it does make me wonder about one thing. If 88% of Tibetans have inherited this genetic advantage that is crucial to their survival, it still means that 12% have not. How do the 12% manage to cope?

    • DaveMed

      They probably suffer from lung disease and right heart failure at fairly early ages.