Haplotipos STRs en cromosomas Y amerindios de poblaciones mexicanas: evidencia genética del origen biparental de la etnia huichol

Abstract

The Y-chromosome (YC) establishes the male gender in humans. It has been described as C®T mutation (M3) that defines the YC origin as Amerindian. The STRs markers have a relatively high mutation rate, which makes it easier to analyze microevolutionary processes. We analyzed the diversification process of Amerindian Y chromosomes (M3) by means of 6 Y-STRs in 129 males from 8 Mexican populations. Our discussion was focused on Huichols, who had the lowest Y-STR genetic diversity, suggesting genetic drift effects and/or founder effects attributable to their geographical isolation. The presence of two principal paternal lineages in the network-joining tree, supported historical and anthropometric records, which indicate that Huichols were formed by the fusion of two ancestral tribes (Diguet 1982); the genetic distances and close haplotype relationship between Huichols and Tarahumaras were in agreement with their linguistic affiliation. The high genetic diversity of Purépechas and wide distribution of their haplotypes, suggest their present genetic composition was influenced by their dominance in western Mesoamerica and/or his late formation in Posclassic time. The Y-haplotypes shared between populations suggest that, among the Amerindian tribes studied herein, the paternal genetic pool of Nahuas could have contributed more importantly to the Mexican-Mestizos.