Tibetan people have multiple adaptations for life at high altitudes


Share post:

The Tibetan people have inherited variants of five different genes that help them live at high altitudes, with one gene originating in the extinct human subspecies, the Denisovans. Hao Hu and Chad Huff of the University of Texas, Houston, and colleagues report these findings in a new study published in PLOS Genetics.

Tibetan people have multiple adaptations for life at high altitudes
The average elevation of Tibet is almost 15,000 feet above sea level 
[Credit: Goh Chai Hin/AFP/Getty Images]

The people of Tibet have survived on an extremely high and arid plateau for thousands of years, due to their amazing natural ability to withstand low levels of oxygen, extreme cold, exposure to UV light and very limited food sources. Researchers sequenced the whole genomes of 27 Tibetans and searched for advantageous genes. The analysis identified two genes already known to be involved in adaptation to high altitude, EPAS1 and EGLN1, as well as two genes related to low oxygen levels, PTGIS and KCTD12.

They also picked out a variant of VDR, which plays a role in vitamin D metabolism and may help compensate for vitamin D deficiency, which commonly affects Tibetan nomads. The Tibetan variant of the EPAS1 gene originally came from the archaic Denisovan people, but the researchers found no other genes related to high altitude with Denisovan roots. Further analysis showed that Han Chinese and Tibetan subpopulations split as early as 44 to 58 thousand years ago, but that gene flow between the groups continued until approximately 9 thousand years ago.

The study represents a comprehensive analysis of the demographic history of the Tibetan population and its adaptations to the challenges of living at high altitudes. The results also provide a rich genomic resource of the Tibetan population, which will aid future genetic studies.

Tatum Simonson adds: “The comprehensive analysis of whole-genome sequence data from Tibetans provides valuable insights into the genetic factors underlying this population’s unique history and adaptive physiology at high altitude. This study provides further context for analyses of other permanent high-altitude populations, who exhibit characteristics distinct from Tibetans despite similar chronic stresses, as well as lowland populations, in whom hypoxia-related challenges, such those inherent to cardiopulmonary disease or sleep apnea, elicit a wide-range of unique physiological responses. Future research efforts will focus on identifying the interplay between various adaptive versus non-adaptive genetic pathways and environmental factors (e.g., hypoxia, diet, cold, UV) in these informative populations to reveal the biological underpinnings of individualized physiological responses.”

Source: PLOS [April 27, 2017]



Related articles

2000 year-old tomb found in western Turkey

Turkish road workers found 2000 years old tomb during the road rehabilitation works in Southern Turkish city of...

Flashback: Symbolic past of early Aegeans revealed at Dhaskalio-Kavos site

A rocky islet and a nearby hillside have yielded evidence of one of Greece’s oldest and most enigmatic...

Sauropod swimmers or walkers?

An international team of scientists, led by the China University of Geosciences in Beijing and including palaeontologists from...

Iron Age gold coins discovered in Kimbolton

A HOARD of gold coins more than 2,000-years-old has been discovered in Kimbolton. The 67 Iron Age coins...

Astronomers discover ancient Egyptian observations of a variable star

The study of the "Demon star", Algol, made by a research group of the University of Helsinki, Finland,...

Remains of horses and chariots found in 3,000-year-old tomb in China

Lying side by side, these horses have drawn a chariot in an ancient tomb for the past 3,000...

Unlocking the secrets of Australia’s mysterious Lake George

The Australian National University is embarking on the most comprehensive study yet of Lake George's mysterious water levels,...

Roman sarcophagi found at construction site

At least seven sarcophagi and human bones from the Roman age have been discovered during construction work in...