Geografía génica de Chile. Distribución regional de los aportes genéticos americanos, europeos y africanos ; Gene geography of Chile. Regional distribution of American, European and African genetic contributions

Abstract

Background: The geographical distribution of genes plays a key role in genetic epidemiology. The Chilean population has three major stem groups (Native American, European and African). Aim: To estimate the regional rate of American, European and African admixture of the Chilean population. Subjects and Methods: Forty single nucleotide polymorphisms (SNP ́s) which exhibit substantially different frequencies between Amerindian populations (ancestry-informative markers or AIM ́s), were genotyped in a sample of 923 Chilean participants to estimate individual genetic ancestry. Results: The American, European and African individual average admixture estimates for the 15 Chilean Regions were relatively homogeneous and not statistically different. However, higher American components were found in northern and southern Chile and higher European components were found in central Chile. A negative correlation between African admixture and latitude was observed. On the average, American and European genetic contributions were similar and significantly higher than the African contribution. Weighted mean American, European and African genetic contributions of 44.34% ± 3 9%, 51.85% ± 5.44% and 3.81% ± 0 .45%, were estimated. Fifty two percent of subjects harbor African genes. Individuals with Aymara and Mapuche surnames have an American admixture of 58.64% and 68.33%, respectively. Conclusions: Half of the Chilean population harbors African genes. Participants with Aymara and Mapuche surnames had a higher American genetic contribution than the general Chilean population. These results confirm the usefulness of surnames as a first approximation to determine genetic ancestry. ; Fil: Fuentes, Macarena. Universidad de Tarapacá; Chile ; Fil: Pulgar, Iván. Centro de investigaciones del Hombre en el desierto; Chile ; Fil: Gallo, Carla. Universidad de Chile; Chile ; Fil: BortolInI, María CátIra. Universidad Peruana Cayetano Heredia; Perú ; Fil: Quinteros, Samuel Canizales. Institutonacional de Ciencias Médicas y Nutrición "Salvador Zubirán"; México. Universidad Nacional Autónoma de México; México ; Fil: Bedoya, Gabriel. Universidad de Antioquia; Colombia ; Fil: Gonzalez Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina ; Fil: RuIz LInares, Andrés. University College London; Estados Unidos ; Fil: Rothhammer, FrancIsco. Universidad de Tarapacá; Chile. Universidad de Chile; Chile