It is not found at any significant frequency in populations outside the Americas.

It is, in the most direct mitochondrial sense, a Native American haplogroup.

The girl at the bottom of Hoyo Negro, whose skull morphology had suggested to some researchers that she might represent a separate founding lineage with origins different from most Native Americans, belonged to a mitochondrial haplogroup that is specifically American — one that derived from the same founding population as most or all of the Indigenous peoples of the hemisphere.

The two-migration model had predicted, or at least was compatible with, a different result.