Angelina García

Brief communication: Restricted geographic distribution for Y-Q* paragroup in South America.

We analyzed 21 paragroup Q* Y chromosomes from South American aboriginal and urban populations. Our aims were to evaluate the phylogenetic status, geographic distribution, and genetic diversity in these groups of chromosomes and compare the degree of genetic variation in relation to Q1a3a haplotypes. All Q* chromosomes from our series and five samples from North American Q* presented the derivate state for M346, that is present upstream to M3, and determined Q1a3* paragroup. We found a restrictive geographic distribution and low frequency of Q1a3* in South America. We assumed that this low frequency could be reflecting extreme drift effects. However, several estimates of gene diversity do not support the existence of a severe bottleneck. The mean haplotype diversity expected was similar to that for South American Q1a3* and Q1a3a (0.478 and 0.501, respectively). The analysis of previous reports from other research groups and this study shows the highest frequencies of Q* for the West Corner and the Grand Chaco regions of South America. At present, there is no information on whether the phylogenetic status of Q* paragoup described in previous reports is similar to that of Q1a3* paragroup though our results support this possibility.

Incidence and Distribution of Native American mtDNA Haplogroups in Central Argentina

Abstract We report the incidence and distribution of Native American mtDNA haplogroups in nine villages across the Sierras Centrales archeological area, located in central Argentina. The aims of the study were (1) to investigate the relative incidence of native maternal lineages, (2) to determine whether or not the homogeneous pattern observed in a previous study persists at this larger scale, and (3) to ascertain the genetic affinities between the studied population and other native populations of the Southern Cone of South America. Of the 310 individuals from whom DNA was extracted, 249 (80.3%) were assigned to one of the founding native American haplogroups. This finding confirms the persistence at high prevalence of native maternal lineages in the rural populations of central Argentina. The haplogroup distribution is homogeneous in the population samples from Córdoba province, with haplogroups C and D always found at the highest frequencies. The sample from San Luis province, Tilisarao, presents a different genetic pattern, with haplogroups A and B being the most frequent. Principal components analysis and SAMOVA at the regional level show that the Córdoba, Patagonia, and Tierra del Fuego populations cluster together, which suggests a common origin.

LINAJES PARENTALES AMERINDIOS EN POBLACIONES DEL NORTE DE CORDOBA

espanolSe da a conocer una practica mutilatoria post mortem que hasta el presente nunca fuera reportada en craneos de aborigenes del territorio nacional consistente en la ablacion completa de la cara. Se describen tres ejemplares que la presentan, todos procedentes de un sector de las margenes de la laguna Mar Chiquita (Cordoba). Dos de ellos difieren netamente de los craneos de los aborigenes que habitaban en la region a la llegada de los espanoles, tanto por su morfologia normal como por presentar una rara variedad de la deformacion circular intencional del neurocraneo. EnglishA post mortem mutilating practice consisting of the total ablation of the face, which has not been reported so far in skulls of aborigines of the national territory, is reported. Three examples from the Mar Chiquita lake banks (Cordoba) are described. Due to their morphology two of them are clearly different from aborigines from this region up to the Spainard arriving by their morphology and by their extrange variety of intentional circular deformation of the neurocranium.

Phylogeography of mitochondrial haplogroup D1: An early spread of subhaplogroup D1j from Central Argentina

We analyzed the patterns of variation of haplogroup D1 in central Argentina, including new data and published information from other populations of South America. Almost 28% (107/388) of the individuals sampled in the region belong to haplogroup D1, whereas more than 52% of them correspond to the recently described subhaplogroup D1j (Bodner et al.: Genome Res 22 (2012) 811-820), defined by the presence of additional transitions at np T152C-C16242T-T16311C to the nodal D1 motif. This lineage was found at high frequencies across a wide territory with marked geographical-ecological differences. Additionally, 12 individuals present the mutation C16187T that defines the recently named subhaplogroup D1g (Bodner et al.: Genome Res 22 (2012) 811-820), previously described in populations of Patagonia and Tierra del Fuego. Based on our results and additional data already published, we postulate that the most likely origin of subhaplogroup D1j is the region of Sierras Pampeanas, which occupies the center and part of the northwestern portion of Argentina. The extensive yet restricted geographical distribution, the relatively large internal diversity, and the absence or low incidence of D1j in other regions of South America suggest the existence of an ancient metapopulation covering the Sierras Pampeanas, being this lineage its genetic signature. Further support for a scenario of local origin for D1j in the Sierras Pampeanas stems from the fact that early derivatives from a putative ancestral lineage carrying the transitions T16311C-T152C have only been found in this region, supporting the hypothesis that it might represent an ancestral motif previous to the appearance of D1j-specific change C16242T.

High interpopulation homogeneity in Central Argentina as assessed by Ancestry Informative Markers (AIMs)

The population of Argentina has already been studied with regard to several genetic markers, but much more data are needed for the appropriate definition of its genetic profile. This study aimed at investigating the admixture patterns and genetic structure in Central Argentina, using biparental markers and comparing the results with those previously obtained by us with mitochondrial DNA (mtDNA) in the same samples. A total of 521 healthy unrelated individuals living in 13 villages of the Córdoba and San Luis provinces were tested. The individuals were genotyped for ten autosomal ancestry informative markers (AIMs). Allele frequencies were compared with those of African, European and Native American populations, chosen to represent parental contributions. The AIM estimates indicated a greater influence of the Native American ancestry as compared to previous studies in the same or other Argentinean regions, but smaller than that observed with the mtDNA tests. These differences can be explained, respectively, by different genetic contributions between rural and urban areas, and asymmetric gene flow occurred in the past. But a most unexpected finding was the marked interpopulation genetic homogeneity found in villages located in diverse geographic environments across a wide territory, suggesting considerable gene flow.

Analysis of Uniparental Lineages in Two Villages of Santiago del Estero, Argentina, Seat of Pueblos de Indios in Colonial Times

Abstract Based on the analysis of the mitochondrial control region and seven biallelic markers of the Y chromosome, we investigated the genetic composition of two rural populations of southern Santiago del Estero, Argentina, that were seats in colonial times of pueblos de indios, a colonial practice that consisted of concentrating the indigenous populations in organized and accessible settlements, to facilitate Christianizing and policing. We found the Native American Y chromosome haplogroup Q1a3a in only 11% (3 of 27) of the males. Haplogroup R, common in European populations, is the most frequent haplogroup in Santiago del Estero (55%). In contrast, the persistence of Native American maternal lineages is extremely high (95%). This finding is most likely due to the low incidence in that region of the 20thcentury European wave of migration and to the existence of pueblos de indios from 1612 to the first decades of the 19th century. In contrast to archeological records that suggest Santiago del Estero late pre-Hispanic groups were strongly influenced by the Andean world, we did not find genetic evidence in support of significant gene flow. On the other hand, these populations share many mitochondrial DNA hypervariable region I (HVRI) haplotypes with other populations from the Sierras Pampeanas (particularly with Córdoba) and the Gran Chaco regions.

Genetic variation in populations from central Argentina based on mitochondrial and Y chromosome DNA evidence

We present new data and analysis on the genetic variation of contemporary inhabitants of central Argentina, including a total of 812 unrelated individuals from 20 populations. Our goal was to bring new elements for understanding micro-evolutionary and historical processes that generated the genetic diversity of the region, using molecular markers of uniparental inheritance (mitochondrial DNA and Y chromosome). Almost 76% of the individuals show mitochondrial lineages of American origin. The Native American haplogroups predominate in all surveyed localities, except in one. The larger presence of Eurasian maternal lineages were observed in the plains (Pampas) of the southeast, whereas the African lineages are more frequent in northern Córdoba. On the other hand, the analysis of 258 male samples reveals that 92% of them present Eurasian paternal lineages, 7% carry Native American haplogroups, and only 1% of the males show African lineages. The maternal lineages have high genetic diversity homogeneously distributed throughout central Argentina, probably as result of a recent common origin and sustained gene flow. Migratory events that occurred in colonial and recent times should have contributed to hiding any traces of differentiation that might have existed in the past. The analysis of paternal lineages showed also homogeneous distribution of the variation together with a drastic reduction of the native male population.

Molecular polymorphisms of the ABO locus as informative markers of ancestry in Central Argentina

The aim of this study was to investigate the distribution of molecular polymorphisms of the ABO gene in four population samples from the province of Córdoba, in Central Argentina, and to compare them with other worldwide populations.

Algunas aclaraciones acerca del articulo “Linajes parentales amerindios en poblaciones del norte de Córdoba” (García A, Demarchi DA, Rev. Arg. Antrop. Biol. 8(1):57-71, 2006)

Carta a los directores de la publicacion en referencia a algunos aspectos de la nota citada.

Distribution of a 9.1-kb Insertion-Deletion Polymorphism Among Native and Admixed Populations from Argentina

ABSTRACT We studied five population samples from Argentina, four drawn from Native American groups of the northeast region (Wichí, Pilagá, Toba, and Mbyá-Guaraní) and one from two small villages of the Córdoba province. In this study we report genotypes and allele frequencies of the 9.1-kb insertion-deletion polymorphism located on chromosome 22. The frequency of the deletion allele ranges from 0.276 in the Mbyá-Guaraní to 0.470 in the Pilagá. The coefficient of population differentiation is fairly low (FST = 0.013), does not reflect any geographic or linguistic pattern, and seems to be more related to stochastic processes than to directional forces.