Genetic history of indigenous peoples of the Americas
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.Analyses of genetics among Native American and Siberian populations have been used to argue for early isolation of founding populations on Beringia and for later, more rapid migration from Siberia through Beringia into the New World. 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.