English: Frequency patterns of the main mtDNA hgs (haplogroups) in Argentina in the admixed groups (A) versus the Native American communities (B). NA: Native American component; Eu: European component; Af: sub-Saharan African component. Red dots indicate sampled locations as undertaken in other studies from the literature; blue dots indicate the sampled locations in the present study.

The Native American component observed in the urban populations was 66%, 41%, and 70% in South, Central, and North, respectively and it was virtually 100% in most Native American groups. The distribution of Native American hgs was substantially different in the main Argentinean regions especially when looking at urban populations (Figure A); for instance, hg A2 constitutes 30% in North admixed populations but only 17% in South admixed populations (Figure A) (Pearson's χ² test; un-adjusted P-value = 0.00561). Moreover, the percentages of the different Native American hgs significantly differ when comparing admixed with native populations (Figure A vs Figure B), even when comparing samples from the same geographical location; thus, for example, when considering only the Native American component of the urban populations, hg B2 is 19% in North admixed populations versus 38% in North Natives (Pearson's χ² test; un-adjusted P-value = 0.01808), or hgs B2 and D1 have frequencies of 11% versus 46% (hg B2; Pearson's χ₂ test; un-adjusted P-value < 0.0000) and 46% versus 23% (hg D1; Pearson's χ² test; un-adjusted P-value = 0.00334) in South admixed populations versus South Natives.

The lower prevalence of Native American hgs observed in Central Argentina coincides with the high proportion of European lineages in this region, mirroring the fact that this was the main European settlement area in the country; e.g. the European component is significantly more predominant in Central (56%) than in North (29%; Pearson's χ² test; un-adjusted P-value < 0.00901).