It's a genetic adaptation that allows Tibetans to live in such high altitudes
Now research from the University of Utah has shown a genetic mutation, or adaptation, which helps Tibetans thrive in conditions many of us couldn’t cope with.
Senior author and University of Utah professor of internal medicine, Josef Prchal, MD, needed donations of blood from Tibetans from which he could extract their DNA – but he quickly learned it would be a tough task. It took a letter from the Dalai Lama, the Tibetan spiritual leader, for him to gain their trust.
“The Dalai Lama felt that a better understanding of the adaptation would be helpful not only to the Tibetan community but also to humanity at large,” said Prchal. After the letter, 90 Tibetans from the US and abroad volunteered for the study.
Upon acquiring the DNA, he found it had a fascinating story to tell. About 8,000 years ago, the gene EGLN1 changed by a single DNA base pair. Today, a relatively short time later in the context of human history, 88% have the genetic variation – while it’s virtually absent from closely-related lowland Asians.
Prchal collaborated with fellow senior author Peppi Koivunen, PhD, from Biocenter Oulu in Finland, among others, to determine that the newly-identified genetic variation protects Tibetans by decreasing an over-response to low oxygen.
In those without the adaptation, the thin air causes their blood to become thick with oxygen-carrying red blood cells, often causing long-term complications such as heart failure. The EGLN1 variation, together with other unidentified genetic changes, collectively support life at high altitudes.
These discoveries are just one chapter in a much larger story. The genetic adaptation likely causes other changes to the body that have yet to be understood.