Uniparental genetic markers in Native Americans: A summary of all available data from ancient and contemporary populations.

This study summarizes decades of research conducted in Native American populations for both mtDNA and the Y-chromosome. Continental or sub-continental patterns of variation reveal that most of the genetic variation occurs within populations rather than among linguistic or ecoregional groups, and that isolation by distance is barely detectable in most population sets. The genetic structure among groups was always larger for mtDNA than for the Y-chromosome, suggesting between-sex differences in gene flow.