Mitochondrial DNA haplogroups in Amerindian populations from the Gran Chaco

DEMARCHI DA; PANZETTA-DUTTARI GM; LÓPEZ DE BASUALDO M; MOTRÁN C; MARCELLINO A

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY

Wiley-Liss

Lugar: New York; Año: 2001 vol. 115 p. 199 - 203

0002-9483

Mitochondrial DNA from 141 individuals was typed for diagnostic restriction sites and the 9-bpregion V deletion to examine the distribution of the founding mtDNA lineage haplotypes in three Amerindian populations (Mataco, Toba, and Pilaga) who currently inhabit the Argentinian part of the Gran Chaco. All four lineages were identified in the three tribes and four population samples studied. Disregarding ethnic or geographic origin, haplogroups B and D exhibit high incidenceamong the Gran Chaco inhabitants, whereas haplogroups A and C are present in a lower frequency. Three individuals possess none of the characteristic markers and, therefore, could not be assigned to one of those lineages. A neighbor-joining representation of FST distances reflectsthe current geographic location of the populations, and this also corresponds to their historic distribution.After separating South America into four major regions (Tropical Forest, Andes, Gran Chaco, and Patagonia-Tierra del Fuego), the Gran Chaco populations present the highest average intragroup variability (Hs 5 0.64) as well as the lowest intergroup diversity (GST = 0.06). Thesefindings suggest high levels of gene flow among the Chaco tribes, as well as with neighbor populations from outside the region.