Scientists recreate mammoth blood

David Heath
Monday, 03 May 2010 17:49

Science - Biology

Based on DNA found in frozen bones of mammoth in Siberia, scientists have been able to recreate the main blood protein, haemoglobin and demonstrate how the animals could survive in the cold where humans could not.

Published earlier today in the journal Nature Genetics, the paper entitled "Substitutions in woolly mammoth haemoglobin confer biochemical properties adaptive for cold tolerance," shows how the international research team was able to use modern-day E. coli bacteria as a host in which to re-manufacture the millennia-old DNA.

According to the paper's abstract, "We have genetically retrieved, resurrected and performed detailed structure-function analyses on authentic woolly mammoth hemoglobin to reveal for the first time both the evolutionary origins and the structural underpinnings of a key adaptive physiochemical trait in an extinct species. Hemoglobin binds and carries O2; however, its ability to offload O2 to respiring cells is hampered at low temperatures, as heme deoxygenation is inherently endothermic (that is, hemoglobin-O2 affinity increases as temperature decreases).

"We identify amino acid substitutions with large phenotypic effect on the chimeric β/δ-globin subunit of mammoth hemoglobin that provide a unique solution to this problem and thereby minimize energetically costly heat loss. This biochemical specialization may have been involved in the exploitation of high-latitude environments by this African-derived elephantid lineage during the Pleistocene period. This powerful new approach to directly analyze the genetic and structural basis of physiological adaptations in an extinct species adds an important new dimension to the study of natural selection."

The body of the paper is behind a pay-wall.

According to co-author Professor Alan Cooper, director of the Australian Centre for Ancient DNA, "This is true palaeobiology, as we can study and measure how these animals functioned as if they were alive today."