Portal:Aboriginal peoples in Canada/Selected article/4
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Genetic history of indigenous peoples of the Americas primarily focus on Human Y-chromosome DNA haplogroups and Human mitochondrial DNA haplogroups. Autosomal "atDNA" markers are also used, but differ from mtDNA or Y-DNA in that they overlap significantly. The genetic pattern indicates Indigenous Amerindians experienced two very distinctive genetic episodes; first with the initial peopling of the Americas, and secondly with European colonization of the Americas. The former is the determinant factor for the number of gene lineages, zygosity mutations and founding haplotypes present in today's Indigenous Amerindian populations.
Human settlement of the New World occurred in stages from the Bering sea coast line, with an initial layover on Beringia for the small founding population. The micro-satellite diversity and distributions of the Y lineage specific to South America indicates that certain Amerindian populations have been isolated since the initial colonization of the region. The Na-Dené, Inuit and Indigenous Alaskan populations exhibit haplogroup Q (Y-DNA); however, they are distinct from other indigenous Amerindians with various mtDNA and atDNA mutations. This suggests that the peoples who first settled the northern extremes of North America and Greenland derived from later migrant populations than those who penetrated further south in the Americas. Linguists and biologists have reached a similar conclusion based on analysis of Amerindian language groups and ABO blood group system distributions.
