Estimation of admixture in two venezuelan populations using ancestry informative markers and haplogroups of mitochondrial DNA

Abstract

Ancestral informative markers (AIMs) and mitochondrial DNA (mtDNA) are highly useful to understand the origin of populations and their migration patterns. In this work, admixture was estimated using seven AIMs in 188 Venezuelan individuals, 84 belonging to the state of Guárico and 104 belonging to the central western region of Venezuela (RCO). Mitochondrial ancestry of Guárico was also determined, and both populations were compared according to their origin and historical development. This study constitutes the first approximation to the genetic composition of Guárico, and it is the first report for Venezuela using AIMs. The results revealed that Amerindian and European contributions predominate in these populations, but Amerindian is higher in Guárico (50.57%) than in RCO (44.92%), while European is higher in RCO (38.46% vs. 33.72%). In Guárico mtDNA is predominantly Amerindian (80%), as previously reported for RCO (75%). The Amerindian contribution in Guárico is the highest reported for Venezuela. We conclude that the differences found between both samples could be due to an earlier colonization of RCO and to its moderate industrial development during the nineteenth century. We also conclude that the AIMs used here made a good differentiation of the contribution of the three main ancestral groups at a relatively low cost, so that their use, together with polymorphisms of uniparental origin, allows a better genetic approach to explaining the dynamics of the mixing process giving rise to the current Venezuelan population.