Arlington, VA, September 14 – U.S. researchers have found a genetic trait that enables some Tibetan women to achieve high blood oxygen levels, despite living at oxygen-scarce altitudes.
The trait is associated with higher infant survival, according to researchers at the National Science Foundation. Tibetan mothers who carry the oxygen-enriching gene tend to give birth to infants who are more likely to survive their first year of life.
The team studied mothers and their children in over 900 Tibetan households who lived at altitudes up to about 13,800 feet above sea level — higher than the peak of Hawaii’s volcanic mountain, Mauna Loa, 13,680 feet above sea level.
The researchers measured the women’s blood oxygen and collected genealogical and fertility data, including the numbers of pregnancies and births, surviving children, and other health status factors. Using established statistical analysis techniques, they found one copy of the suspect gene — out of a possible two — gives Tibetan mothers the ability to infuse extra oxygen into their bloodstreams, an important survival asset because it decreases the high-altitude stress of oxygen deficiency.
Children of moms with the genetic advantage were about five times more likely to live to the age of one year than were other children.
