Variabilidad mitocondrial en muestras pre-colombinas de la Patagonia argentina: Hacia una visión de su poblamiento desde el ADN antiguo

Abstract

Different disciplines have attempted to explain the settlement and evolution of the hunter gatherer populations who lived in the Argentinean Patagonia. Both archaeology and cranial morphology have suggested an initial settlement stage characterized by low demography, divergence events, and serial founder effects. These assumptions were supported by mitochondrial DNA analysis of extant native populations; studies in preColumbian groups being as yet scarce. In order to increase the information available, a total of 50 samples of individuals from archaeological sites and museum collections of various Patagonian regions, dated It was possible to assign maternal lineage in 27 samples by RFLP analysis and in 22 of them hypervariable region 1 was sequenced. Lineages A2, C1, D1, D1g, D1j and D4h3a were detected. Statistical analysis of the results obtained here suggested a tendency towards a lower mitochondrial diversity southward. Comparison of the geographical regions analyzed has shown no statistically significant differences or population structure, which may indicate a recent common origin and the existence of gene flow across regions during the late Holocene. Additionally, a change in the mitochondrial gene pool can be proposed in current native populations due to the high frequency of lineage B2, possibly related to the process of araucanization begun in the sixteenth century.