Tibetan genes evolved fastest out of all races
Published 03/07/2010 | 05:00
TIBETANS' genetic make-up evolved to cope with high altitude in under 3,000 years, research has shown.
The mountain-living people have unusual gene variants that help their bodies use oxygen.
A new US study suggests they appeared by natural selection after Tibetans parted from the Han Chinese ethnic group less than 3,000 years ago.
"This is the fastest genetic change ever observed in humans," said Professor Rasmus Nielsen, from the University of California at Berkeley.
"For such a strong change, a lot of people would have had to die simply due to the fact that they had the wrong gene."
One mutation that is widespread in Tibetans is believed to involve the "super athlete gene" EPAS1 -- so called because its variants are associated with improved athletic performance.
Most people are affected by altitude when they try living at heights above 13,000 feet, where oxygen levels are about 40pc lower than at sea level.
They tire easily, develop headaches, produce babies with lower birth weights and have a higher infant death rate. However, Tibetans suffer none of these problems.