RESUMO
OBJECTIVES: Artificial deformation of the cranium in humans has been related to powerful environmental-cultural stimuli that modify vectors of growth and development when the cranium is still malleable. Osteological differentiation into deformed and nondeformed remains enables the morphological information of individuals that make up ethnic groups or populations to be separately contrasted, the invariant measurements of deformation to be identified, the information provided by archeological remains to be placed in a social context, the cranial variation to be related to genetic variation (individuals without deformation), and predictions to be made (in the absence of direct genetic information). METHODS: With samples of reduced size and many variables, we propose a decision rule based on: (a) pre-selecting variables (Kruskal-Wallis and Λ-Wilks test); (b) applying logistic regression to obtain the optimal classification criterion; and (c) defining a multi-criterion decision rule to bring about greater robustness. RESULTS: After applying the decision rule to a sample of 180 crania (71 from the Selknam, 74 from the Yamana, and 35 from the Alakaluf ethnic groups), it was possible to identify the Selknam men with frontal deformation and the Yamana women with flattening of the parietal regions at the height of the bregma. CONCLUSIONS: From there on with the information provided by the graphical representation of the populations in the most informative dimensions and the homogeneity contrast between sexes, we related the frontal deformation in Selknam men to dragging firewood, vegetable matter, domestic utensils, and heavy pieces of meat from the hunt. On the other hand, the flattening of the parietal areas at the height of the bregma in Yamana women is related to loading and transporting vegetables and animals in baskets or leather sacks.
Assuntos
Cefalometria/estatística & dados numéricos , Indígenas Sul-Americanos/estatística & dados numéricos , Crânio/anatomia & histologia , Antropologia Física , Argentina , Chile , Feminino , Humanos , Masculino , Crânio/patologiaRESUMO
Numerous studies of human populations in Europe and Asia have revealed a concordance between their extant genetic structure and the prevailing regional pattern of geography and language. For native South Americans, however, such evidence has been lacking so far. Therefore, we examined the relationship between Y-chromosomal genotype on the one hand, and male geographic origin and linguistic affiliation on the other, in the largest study of South American natives to date in terms of sampled individuals and populations. A total of 1,011 individuals, representing 50 tribal populations from 81 settlements, were genotyped for up to 17 short tandem repeat (STR) markers and 16 single nucleotide polymorphisms (Y-SNPs), the latter resolving phylogenetic lineages Q and C. Virtually no structure became apparent for the extant Y-chromosomal genetic variation of South American males that could sensibly be related to their inter-tribal geographic and linguistic relationships. This continent-wide decoupling is consistent with a rapid peopling of the continent followed by long periods of isolation in small groups. Furthermore, for the first time, we identified a distinct geographical cluster of Y-SNP lineages C-M217 (C3*) in South America. Such haplotypes are virtually absent from North and Central America, but occur at high frequency in Asia. Together with the locally confined Y-STR autocorrelation observed in our study as a whole, the available data therefore suggest a late introduction of C3* into South America no more than 6,000 years ago, perhaps via coastal or trans-Pacific routes. Extensive simulations revealed that the observed lack of haplogroup C3* among extant North and Central American natives is only compatible with low levels of migration between the ancestor populations of C3* carriers and non-carriers. In summary, our data highlight the fact that a pronounced correlation between genetic and geographic/cultural structure can only be expected under very specific conditions, most of which are likely not to have been met by the ancestors of native South Americans.
Assuntos
Cromossomos Humanos Y/genética , Haplótipos/genética , Indígenas Sul-Americanos/genética , Repetições de Microssatélites/genética , América Central , Europa (Continente) , Genótipo , Geografia , Humanos , Idioma , Linguística , Masculino , Filogenia , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/genética , América do SulRESUMO
Seventeen Y-STRs included in AmpFlSTR Yfiler PCR Amplification Kit (Applied Biosystems, USA) were studied in males from a multi ethnical population from El Beni Department (North Bolivia). Haplotypic and allelic frequencies were reported. Comparison of El Beni population with other samples from the region was carried out through Multidimensional Scalling over Rst distances matrix.
Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Haplótipos , Sequências de Repetição em Tandem , Bolívia , Impressões Digitais de DNA , Frequência do Gene , Humanos , Masculino , Reação em Cadeia da PolimeraseRESUMO
This report presents allele frequency and absolute genotype data of the short tandem repeat (STR) loci HUMTH01, HUMVWA31A, HUMCSF1PO and HUMTPOX for three autochthonous Amerindian populations living in the Beni Department of Bolivia. These related groups are the Quechua, Aymara and Beni populations all living in specific although sometimes overlapping areas that extend from the Andean habitat to the lowland Llanos de Moxos savannah passing through the Piedmont hills. The usefulness of these loci for paternity and identification testing was also examined. The present work completes previous genetic studies performed by the authors in these populations including mtDNA haplogroups (Bert et al., Hum Biol, 73:1-16, 2001) and HVRI data (Bert et al., Ann Hum Biol 31:9-28, 2004; Corella et al., Ann Hum Biol 34:34-35, 2007).
Assuntos
Indígenas Sul-Americanos/genética , Polimorfismo Genético , Sequências de Repetição em Tandem/genética , Bolívia , Feminino , Frequência do Gene , Geografia , Heterozigoto , Humanos , Desequilíbrio de Ligação/genética , Masculino , Análise de Componente PrincipalRESUMO
BACKGROUND: Chimane, Moseten Aymara and Quechua are Amerindian populations living in the Bolivian Piedmont, a characteristic ecoregion between the eastern slope of the Andean mountains and the Amazonian Llanos de Moxos. In both neighbouring areas, dense and complex societies have developed over the centuries. The Piedmont area is especially interesting from a human peopling perspective since there is no clear evidence regarding the genetic influence and peculiarities of these populations. This land has been used extensively as a territory of economic and cultural exchange between the Andes and Amazonia, however Chimane and Moseten populations have been sufficiently isolated from their neighbour groups to be recognized as distinct populations. Genetic information suggests that evolutionary processes, such as genetic drift, natural selection and genetic admixture have formed the history of the Piedmont populations. AIM: The objective of this study is to characterize the genetic diversity of the Piedmont populations, analysing the sequence variability of the HVR-I control region in the mitochondrial DNA (mtDNA). Haplogroup mtDNA data available from the whole of Central and South America were utilized to determine the relationship of the Piedmont populations with other Amerindian populations. SUBJECT AND METHODS: Hair pulls were obtained in situ, and DNA from non-related individuals was extracted using a standard Chelex 100 method. A 401 bp DNA fragment of HVR-I region was amplified using standard procedures. Two independent 401 and 328 bp DNA fragments were sequenced separately for each sample. The sequence analyses included mismatch distribution and mean pairwise differences, median network analyses, AMOVA and principal component analyses. The genetic diversity of DNA sequences was measured and compared with other South Amerindian populations. RESULTS: The genetic diversity of 401 nucleotide mtDNA sequences, in the hypervariable Control Region, from positions 16 000-16 400, was characterized in a sample of 46 Amerindians living in the Piedmont area in the Beni Department of Bolivia. The results obtained indicate that the genetic diversity in the area is higher than that observed in other American groups living in much larger areas and despite the reduced size of the studied area the human groups analysed show high levels of inter-group variability. In addition, results show that Amerindian populations living in the Piedmont are genetically more related to those in the Andean than in the Amazonian populations.
Assuntos
DNA Mitocondrial/genética , Variação Genética , Genética Populacional/métodos , Indígenas Sul-Americanos/genética , Bolívia , Cabelo , Haplótipos , Humanos , Filogenia , Análise de Componente Principal , Análise de Sequência de DNARESUMO
Ancient mtDNA was successfully recovered from 24 skeletal samples of a total of 60 ancient individuals from Patagonia-Tierra del Fuego, dated to 100-400 years BP, for which consistent amplifications and two-strand sequences were obtained. Y-chromosome STRs (DYS434, DYS437, DYS439, DYS393, DYS391, DYS390, DYS19, DYS389I, DYS389II, and DYS388) and the biallelic system DYS199 were also amplified, Y-STR alleles could be characterized in nine cases, with an average of 4.1 loci per sample correctly typed. In two samples of the same ethnic group (Aonikenk), an identical and complete eight-loci haplotype was recovered. The DYS199 biallelic system was used as a control of contamination by modern DNA and, along with DYS19, as a marker of American origin. The analysis of both mtDNA and Y-STRs revealed DNA from Amerindian ancestry. The observed polymorphisms are consistent with the hypothesis that the ancient Fuegians are close to populations from south-central Chile and Argentina, but their high nucleotide diversity and the frequency of single lineages strongly support early genetic differentiation of the Fuegians through combined processes of population bottleneck, isolation, and/or migration, followed by strong genetic drift. This suggests an early genetic diversification of the Fuegians right after their arrival at the southernmost extreme of South America.