May 30, 2008

mtDNA haplogroup D2a1 in Paleo-Eskimo human

Ancient hair suggests multiple migrations into Americas
An ancient tuft of dark-brown human hair suggests that a tribe of humans trekked from north Asia to settle in what is now Greenland 3500 years ago – and then vanished.

A team of Danish scientists has found that DNA collected from the hair traces back to Asians, not Native Americans or the Eskimos that currently populate the region. This suggests that the first humans to colonise the American Arctic were distinct from the first people who arrived in America more than 14,000 years ago.

The hair – found in northern Greenland – may even be a relic of a steady trickle of human migrations across a harsh Arctic landscape, says evolutionary anthropologist Tom Gilbert of Copenhagen University in Denmark, who led the study. "It's bloody hard work to colonise the Arctic. It is not an easy venture," he adds.

Science DOI: 10.1126/science.1159750

Paleo-Eskimo mtDNA Genome Reveals Matrilineal Discontinuity in Greenland

M. Thomas et al.

The Paleo-Eskimo Saqqaq and Independence I cultures, documented from archaeological remains in Northern Canada and Greenland, represent the earliest human expansion into the New World’s northern extremes. However, their origin and genetic relationship to later cultures is unknown. We sequenced a mitochondrial genome from a Paleo-Eskimo human, using 3400- to 4500-year-old frozen hair excavated from an early Greenlandic Saqqaq settlement. The sample is distinct from modern Native Americans and Neo-Eskimos, falling within haplogroup D2a1, a group previously observed among modern Aleuts and Siberian Sireniki Yuit. This suggests that the earliest migrants into the New World’s northern extremes derived from populations in the Bering Sea area, and were neither directly related to Native Americans nor the later Neo-Eskimos that replaced them.


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