People in frigid cold evolved changes in fat metabolism, shivering
BOSTON— Siberians may use genes to stay warm, a new study shows.
As part of an effort to catalog genetic diversity in Siberia, Alexia Cardona of the University of Cambridge and collaborators sampled DNA from 200 Siberians representing 10 native groups. The team looked for genes that have more changes in Siberians than would be expected by chance — a sign that the genes evolved rapidly in the 24,000 years since people settled the frigid land. Rapid changes suggest that a gene is important for adapting to an environment.
Several of the Siberians’ genes have variants that may help keep Arctic dwellers warm during the long winters, Cardona reported October 24 at the annual meeting of the American Society of Human Genetics. Among the candidates for genetic heaters are genes involved in metabolizing fats. Some Siberian groups eat mostly meat, so genes that help convert animal fat to energy are important for creating heat.
Another gene with variants unique to Siberians is called PRKG1; it helps regulate body heat by controlling muscle contraction and the constriction and dilation of blood vessels. Muscle contractions are an important part of shivering, which can raise body temperature.
The researchers also identified variants in genes involved in thyroid function, which plays a role in temperature regulation.
A. Cardona et al. Genome-wide analysis of cold adaption in indigenous Siberian populations. American Society of Human Genetics annual meeting, Boston, October 24, 2013.
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