title: Arrival of Paleo-Indians to the southern cone of South America: new clues from mitogenomes.
abstract: With analyses of entire mitogenomes, studies of Native American mitochondrial DNA (MTDNA) variation have entered the final phase of phylogenetic refinement: the dissection of the founding haplogroups into clades that arose in America during and after human arrival and spread. Ages and geographic distributions of these clades could provide novel clues on the colonization processes of the different regions of the double continent. As for the Southern Cone of South America, this approach has recently allowed the identification of two local clades (D1g and D1j) whose age estimates agree with the dating of the earliest archaeological sites in South America, indicating that Paleo-Indians might have reached that region from Beringia in less than 2000 years. In this study, we sequenced 46 mitogenomes belonging to two additional clades, termed B2i2 (former B2l) and C1b13, which were recently identified on the basis of mtDNA control-region data and whose geographical distributions appear to be restricted to Chile and Argentina. We confirm that their mutational motifs most likely arose in the Southern Cone region. However, the age estimate for B2i2 and C1b13 (11-13,000 years) appears to be younger than those of other local clades. The difference could reflect the different evolutionary origins of the distinct South American-specific sub-haplogroups, with some being already present, at different times and locations, at the very front of the expansion wave in South America, and others originating later in situ, when the tribalization process had already begun. A delayed origin of a few thousand years in one of the locally derived populations, possibly in the central part of Chile, would have limited the geographical and ethnic diffusion of B2i2 and explain the present-day occurrence that appears to be mainly confined to the Tehuelche and Araucanian-speaking groups.
authors.affiliation: Instituto de Ecología y Biodiversidad, Departamento de Ecología, Facultad de Ciencias, Universidad de Chile, Ñuñoa, Santiago, Chile.
authors.forename: Michelle
authors.initials: M
authors.lastname: de Saint Pierre
authors.forename: Francesca
authors.initials: F
authors.lastname: Gandini
authors.forename: Ugo A
authors.initials: UA
authors.lastname: Perego
authors.forename: Martin
authors.initials: M
authors.lastname: Bodner
authors.forename: Alberto
authors.initials: A
authors.lastname: Gómez-Carballa
authors.forename: Daniel
authors.initials: D
authors.lastname: Corach
authors.forename: Norman
authors.initials: N
authors.lastname: Angerhofer
authors.forename: Scott R
authors.initials: SR
authors.lastname: Woodward
authors.forename: Ornella
authors.initials: O
authors.lastname: Semino
authors.forename: Antonio
authors.initials: A
authors.lastname: Salas
authors.forename: Walther
authors.initials: W
authors.lastname: Parson
authors.forename: Mauricio
authors.initials: M
authors.lastname: Moraga
authors.forename: Alessandro
authors.initials: A
authors.lastname: Achilli
authors.forename: Antonio
authors.initials: A
authors.lastname: Torroni
authors.forename: Anna
authors.initials: A
authors.lastname: Olivieri
mesh_terms: D044466:Asian People / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D054629:Genome, Mitochondrial; D006239:Haplotypes; D006801:Humans; D007198:Indians, North American / Q000235:genetics*; D010802:Phylogeny; D013020:South America
chemical_list: D004272:DNA, Mitochondrial