Genetic variation in the New World: ancient teeth, bone, and tissue as sources of DNA.

Examination of ancient and contemporary Native American mtDNA variation via diagnostic restriction sites and the 9-bp Region V deletion suggests a single wave of migration into the New World. This is in contrast to data from Torroni et al. which suggested two waves of migration into the New World (the NaDene and Amerind). All four founding lineage types are present in populations in North, Central, and South America suggesting that all four lineages came over together and spread throughout the New World. Ancient Native American DNA shows that all four lineages were present before European contact in North America, and at least two were present in South America. The presence of all four lineages in the NaDene and the Amerinds argues against separate migrations founding these two groups, although admixture between the groups is still a viable explanation for the presence of all four types in the NaDene.