-
[show abstract]
[hide abstract]
ABSTRACT: The relationship between the "individualism-collectivism" and the serotonin trans-porter functional polymorphism (5-HTTLPR), suggested in the previous reports, was tested in Native South Amerindian populations. A total of 170 individuals from 21 populations were genotyped for the 5-HTTLPR alleles. For comparative purposes, these populations were classified as individualistic (recent history of hunter–gathering) or collectivistic (agriculturalists). These two groups showed an almost identical S allele frequency (75 and 76%, respectively). The analysis of molecular variance showed no structural differences between them. Behavioral typologies like those sug-gested by JY Chiao and KD Blizinsky (Proc R Soc B 277 (2010) 529–537) are always a simplification of complex phenomena and should be regarded with caution. In addition, classification of a whole nation in the individu-alist/collectivist dichotomy is controversial. The focus on modes of subsistence in preindustrial societies, as was tested here, may be a good alternative although the postulated association between the 5-HTTLPR S allele and the collectivist societies was not confirmed. Am J Phys Anthropol 000:000–000, 2013. V C 2013 Wiley Periodicals, Inc.
American Journal of Physical Anthropology 05/2013; · 2.82 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The relationship between the "individualism-collectivism" and the serotonin transporter functional polymorphism (5-HTTLPR), suggested in the previous reports, was tested in Native South Amerindian populations. A total of 170 individuals from 21 populations were genotyped for the 5-HTTLPR alleles. For comparative purposes, these populations were classified as individualistic (recent history of hunter-gathering) or collectivistic (agriculturalists). These two groups showed an almost identical S allele frequency (75 and 76%, respectively). The analysis of molecular variance showed no structural differences between them. Behavioral typologies like those suggested by JY Chiao and KD Blizinsky (Proc R Soc B 277 () 529-537) are always a simplification of complex phenomena and should be regarded with caution. In addition, classification of a whole nation in the individualist/collectivist dichotomy is controversial. The focus on modes of subsistence in preindustrial societies, as was tested here, may be a good alternative although the postulated association between the 5-HTTLPR S allele and the collectivist societies was not confirmed. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.
American Journal of Physical Anthropology 05/2013; · 2.82 Impact Factor
-
-
[show abstract]
[hide abstract]
ABSTRACT: Native Americans are characterized by specific and unique patterns of genetic and cultural/lin-guistic diversities, and this information has been used to understand patterns of geographic dispersion, and the relationship between these peoples. Particularly interest-ing are the Tupi and Je speaker dispersions. At present, a large number of individuals speak languages of these two stocks; for instance, Tupi-Guarani is one of the official lan-guages in Paraguay, Bolivia, and the Mercosul economic block. Although the Tupi expansion can be compared in importance to the Bantu migration in Africa, little is known about this event relative to others. Equal and even deeper gaps exist concerning the Je-speakers' expansion. This study aims to elucidate some aspects of these success-ful expansions. To meet this purpose, we analyzed Native American mtDNA complete control region from nine dif-ferent populations and included HVS-I sequences avail-able in the literature, resulting in a total of 1,176 samples investigated. Evolutionary relationships were explored through median-joining networks and genetic/geographic/ linguistic correlations with Mantel tests and spatial auto-correlation analyses. Both Tupi and Je showed general traces of ancient or more recent fission–fusion processes, but a very different pattern of demographic expansion. Tupi populations displayed a classical isolation-by-dis-tance pattern, while Je groups presented an intricate and nonlinear mode of dispersion. We suggest that the collec-tive memory and other cultural processes could be impor-tant factors influencing the fission–fusion events, which likely contributed to the genetic structure, evolution, and dispersion of Native American populations. Am J Phys Anthropol 000:000–000, 2013. V
American Journal of Physical Anthropology 01/2013; · 2.82 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Native Americans are characterized by specific and unique patterns of genetic and cultural/linguistic diversities, and this information has been used to understand patterns of geographic dispersion, and the relationship between these peoples. Particularly interesting are the Tupi and Je speaker dispersions. At present, a large number of individuals speak languages of these two stocks; for instance, Tupi-Guarani is one of the official languages in Paraguay, Bolivia, and the Mercosul economic block. Although the Tupi expansion can be compared in importance to the Bantu migration in Africa, little is known about this event relative to others. Equal and even deeper gaps exist concerning the Je-speakers' expansion. This study aims to elucidate some aspects of these successful expansions. To meet this purpose, we analyzed Native American mtDNA complete control region from nine different populations and included HVS-I sequences available in the literature, resulting in a total of 1,176 samples investigated. Evolutionary relationships were explored through median-joining networks and genetic/geographic/linguistic correlations with Mantel tests and spatial autocorrelation analyses. Both Tupi and Je showed general traces of ancient or more recent fission-fusion processes, but a very different pattern of demographic expansion. Tupi populations displayed a classical isolation-by-distance pattern, while Je groups presented an intricate and nonlinear mode of dispersion. We suggest that the collective memory and other cultural processes could be important factors influencing the fission-fusion events, which likely contributed to the genetic structure, evolution, and dispersion of Native American populations. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.
American Journal of Physical Anthropology 01/2013; · 2.82 Impact Factor
-
Jorge Gómez-Valdés,
Tábita Hünemeier,
Mirsha Quinto-Sánchez,
Carolina Paschetta,
Soledad de Azevedo,
Marina F González,
Neus Martínez-Abadías,
Mireia Esparza,
Héctor M Pucciarelli, Francisco M Salzano,
Claiton H D Bau,
Maria Cátira Bortolini,
Rolando González-José
[show abstract]
[hide abstract]
ABSTRACT: Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual's fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.
PLoS ONE 01/2013; 8(1):e52317. · 4.09 Impact Factor
-
Jorge A Gómez-Valdés,
Tábita Hünemeier,
Verônica Contini,
Victor Acuña-Alonzo,
Gastón Macin,
Mónica Ballesteros-Romero,
Pau Corral,
Andres Ruiz-Linares,
Gabriela Sánchez-Mejorada,
Samuel Canizales-Quinteros,
Neus Martínez-Abadías, Francisco M Salzano,
Rolando González-José,
Maria Cátira Bortolini
[show abstract]
[hide abstract]
ABSTRACT: OBJECTIVES: The polymorphic site rs4647905 of the FGFR1 gene was previously associated with a decrease in cephalic index (CI). Here, we evaluate the relationships between genotypes and cephalometric measurements and indices in one Mexican Native and two mestizo Mexican populations using two haplotype-tag SNPs (rs4647905 and rs3213849) that represent >85% of the FGFR1 variability, plus three other SNPs (rs2293971, rs2304000, and rs930828) situated nearby. In addition, we genotyped five South American natives, two European, one African, and one Siberian populations to evaluate their intra and intercontinental population diversity. METHODS: The five SNPs were tested and the craniofacial measurements and indices were collected using standardized procedures. Principal Component Analysis was used to verify individual/population comparisons. Associations were performed through the generalized linear model (GLM), coefficient of determination R(2) and linear regression tests. RESULTS: We found a tendency for a decrease in CI in individuals homozygous for allele rs4647905C, regardless of the population to which they belong, though the effect is more pronounced in mestizo. When the GLM analyses were performed using the absolute/linear cephalometric measurements, a statistically significant association was found between four SNPs and head length in the mestizo population. CONCLUSIONS: FGFR1 polymorphisms, especially rs4647905, can have an important role in the normal human skull variation, primarily due to their influence in head length, which would affect other cephalometric absolute/linear measures as well as indices like CI as a result of the pervasive nature of the morphological integration that characterizes the human skull. Am. J. Hum. Biol. 2012. © 2012 Wiley Periodicals, Inc.
American Journal of Human Biology 10/2012; · 2.27 Impact Factor
-
David Reich,
Nick Patterson,
Desmond Campbell,
Arti Tandon,
Stéphane Mazieres,
Nicolas Ray,
Maria V Parra,
Winston Rojas,
Constanza Duque,
Natalia Mesa, [......],
Jean-Michel Dugoujon,
Georges Larrouy,
William Klitz,
Damian Labuda,
Judith Kidd,
Kenneth Kidd,
Anna Di Rienzo,
Nelson B Freimer,
Alkes L Price,
Andrés Ruiz-Linares
[show abstract]
[hide abstract]
ABSTRACT: The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved. One contentious issue is whether the settlement occurred by means of a single migration or multiple streams of migration from Siberia. The pattern of dispersals within the Americas is also poorly understood. To address these questions at a higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. Here we show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call 'First American'. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan speakers on both sides of the Panama isthmus, who have ancestry from both North and South America.
Nature 07/2012; 488(7411):370-4. · 36.28 Impact Factor
-
David Reich,
Nick Patterson,
Desmond Campbell,
Arti Tandon,
Stéphane Mazieres,
Nicolas Ray,
Maria V Parra,
Winston Rojas,
Constanza Duque,
Natalia Mesa, [......],
Jean-Michel Dugoujon,
Georges Larrouy,
William Klitz,
Damian Labuda,
Judith Kidd,
Kenneth Kidd,
Anna Di Rienzo,
Nelson B Freimer,
Alkes L Price,
Andrés Ruiz-Linares
[show abstract]
[hide abstract]
ABSTRACT: The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved 1–5 . One contentious issue is whether the settlement occurred by means of a single 6–8 migration or multiple streams of migration from Siberia 9–15 . The pattern of dispersals within the Americas is also poorly understood. To address these questions at a higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. Here we show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call 'First American'. However, speakers of Eskimo–Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan speakers on both sides of the Panama isthmus, who have ancestry from both North and South America. The settlement of the Americas occurred at least 15,000 years ago through Beringia, a land bridge between Asia and America that existed during the ice ages 1–5 . Most analyses of Native American genetic diversity have examined single loci, particularly mitochondrial DNA or the Y chromosome, and some interpretations of these data model the settlement of America as a single migratory wave from Asia 6–8 . We assembled native population samples from Canada to the southern tip of South America, genotyped them on single nucleotide polymorphism (SNP) microarrays, and merged our data with six other data sets. The combined data set consists of 364,470 SNPs genotyped in 52 Native American populations (493 samples; Fig. 1a and Supplementary Table 1), 17 Siberian populations (245 samples; Supplementary Fig. 1 and Supplementary Table 2) and 57 other populations (1,613 samples) (Supplementary Notes). A complication in studying Native American genetic history is admixture with European and African immigrants since 1492. Cluster analysis 16 shows that many of the samples we examined have some non-native admixture (an average of 8.5%; Fig. 1b and Supplementary Tables 1 and 3). This admixture is a challenge for learning about the historical relationships among the populations, and to address this complication we used three independent approaches. First, we restricted analyses to 163 Native Americans from 34 populations without evidence of admixture (Supplementary Notes). Second, we subtracted the expected contribution of European and African ancestry to the statistics we used to learn about population relation-ships (Supplementary Notes). Third, we inferred the probability of non-native ancestry at each genomic segment and 'masked' segments with more than a negligible probability of this ancestry (Fig. 1b,
Nature 07/2012; · 36.28 Impact Factor
-
Tá Bita,
Hü Nemeier,
Carlos Eduardo,
Guerra Amorim,
Soledad Azevedo,
Veronica Contini,
Víctor Acuñ,
Alonzo,
Francisco Rothhammer,
Jean-Michel Dugoujon, [......],
Ramiro Barrantes,
Teresa María,
Villarreal-Molina,
Vanessa Rodrigues Paixã,
Cô,
Rtes, Francisco M Salzano,
Samuel Canizales-Quinteros,
Andres Ruiz-Linares,
Maria Cá Tira Bortolini
[show abstract]
[hide abstract]
ABSTRACT: Culture and genetics rely on two distinct but not isolated transmission systems. Cultural processes may change the human selective environment and thereby affect which individuals survive and reproduce. Here, we evaluated whether the modes of subsistence in Native American populations and the frequencies of the ABCA1*Arg230Cys polymorphism were correlated. Further, we examined whether the evolutionary consequences of the agriculturally constructed niche in Mesoamerica could be considered as a gene-culture coevolution model. For this purpose, we genotyped 229 individuals affiliated with 19 Native American populations and added data for 41 other Native American groups (n = 1905) to the analysis. In combination with the SNP cluster of a neutral region, this dataset was then used to unravel the scenario involved in 230Cys evolutionary history. The estimated age of 230Cys is compatible with its origin occurring in the American continent. The correlation of its frequencies with the archeological data on Zea pollen in Mesoamerica/Central America, the neutral coalescent simulations, and the F ST -based natural selection analysis suggest that maize domestication was the driving force in the increase in the frequencies of 230Cys in this region. These results may represent the first example of a gene-culture coevolution involving an autochthonous American allele. Copyright: ß 2012 Hü nemeier et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This study was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnoló gico (CNPq); Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS), PRONEX (Brazil); Programme Interdisciplinaire CNRS: Amazonie-Analyse, Modélisation et Ingénierie des Systèmes Amazoniens (France); and Convenio de Desempeñ o Mecesup 2/UTA (Chile). These funding agencies had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist.
PLoS ONE 06/2012; · 4.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Human pigmentation is regulated by several genes acting at different stages of melanin formation. Functional and association studies have elucidated the role of several of these genes in pigmentation phenotypes. Forensic and evolutionary studies can benefit from this knowledge.
To evaluate the reliability of the prediction of pigmentation phenotypes using a large database of genetic markers in individuals with known phenotypes; and from this try to predict the pigmentation phenotype of prehistoric Homo specimens and of contemporary individuals whose visible phenotypes are not known.
We compared predicted and observed phenotypic data through an analysis of 124 single nucleotide polymorphisms in 33 genic and seven intergenic regions of 30 subjects, five of them prehistoric, whose complete nuclear genomes are available in UCSC and PSU UCSC public databases.
For the molecular predicted versus observed phenotypes, the percentage of agreement was as follows: freckles: 91; skin: 64; hair: 44; eyes: 36; total: 59; while the molecular predicted versus probable (no visible observation available; inferences based on ethnic population characteristics) it was, respectively, 83, 60, 42, 67, and 63. The difference between two sets is statistically nonsignificant (P = 0.75).
To our knowledge, this is the first article to examine the effect of a large number of genetics markers for phenotype prediction. The approach could be useful for forensic applications, as well as for the determination of possible phenotypes of extinct prehistoric individuals.
American Journal of Human Biology 03/2012; 24(5):705-9. · 2.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Lactase persistence (LP) is the phenotypic trait in which lactase secretion is maintained during adulthood. LP is due to mutations in the LCT enhancer region, located 14-kb upstream of the gene. In Europeans, the -13910*T allele is associated with LP. In Africans this allele is rare while other mutations in this same region were related to LP. The LCT is highly polymorphic in human populations, but so far Brazilian Amerindians had not been investigated for these polymorphisms or for the presence of LP mutations. We describe the genetic diversity of the LCT region and the presence of LP enhancer mutations in four native Brazilian populations (Guarani-Kaiowá, Guarani-Ñandeva, Kaingang, and Xavante). Twelve polymorphisms were genotyped by PCR-based methods. The -13910*T allele varied from 0.5% in the Xavante to 7.6% in the Guarani-Ñandeva. These frequencies probably derive from European sources and they correlate with non-native admixture proportions previously estimated for these groups. But since admixture is virtually absent in the Xavante, we suggest that the presence of the LP allele could have been determined by a de novo mutation. No other mutations in the -14 kb enhancer region were found. The LCT was highly polymorphic in the present sample showing 15 haplotypes with a heterogeneous distribution among the four Amerindian populations. This diversity could be due to drift, as indicated by the neutrality test performed.
American Journal of Physical Anthropology 03/2012; 147(3):427-32. · 2.82 Impact Factor
-
Tábita Hünemeier,
Carlos Eduardo Guerra Amorim,
Soledad Azevedo,
Veronica Contini,
Víctor Acuña-Alonzo,
Francisco Rothhammer,
Jean-Michel Dugoujon,
Stephane Mazières,
Ramiro Barrantes,
María Teresa Villarreal-Molina,
Vanessa Rodrigues Paixão-Côrtes, Francisco M Salzano,
Samuel Canizales-Quinteros,
Andres Ruiz-Linares,
Maria Cátira Bortolini
[show abstract]
[hide abstract]
ABSTRACT: Culture and genetics rely on two distinct but not isolated transmission systems. Cultural processes may change the human selective environment and thereby affect which individuals survive and reproduce. Here, we evaluated whether the modes of subsistence in Native American populations and the frequencies of the ABCA1*Arg230Cys polymorphism were correlated. Further, we examined whether the evolutionary consequences of the agriculturally constructed niche in Mesoamerica could be considered as a gene-culture coevolution model. For this purpose, we genotyped 229 individuals affiliated with 19 Native American populations and added data for 41 other Native American groups (n = 1905) to the analysis. In combination with the SNP cluster of a neutral region, this dataset was then used to unravel the scenario involved in 230Cys evolutionary history. The estimated age of 230Cys is compatible with its origin occurring in the American continent. The correlation of its frequencies with the archeological data on Zea pollen in Mesoamerica/Central America, the neutral coalescent simulations, and the F(ST)-based natural selection analysis suggest that maize domestication was the driving force in the increase in the frequencies of 230Cys in this region. These results may represent the first example of a gene-culture coevolution involving an autochthonous American allele.
PLoS ONE 01/2012; 7(6):e38862. · 4.09 Impact Factor
-
Marilza S Jota,
Daniela R Lacerda,
José R Sandoval,
Pedro Paulo R Vieira,
Simone S Santos-Lopes,
Rafael Bisso-Machado,
Vanessa R Paixão-Cortes,
Susana Revollo,
Cesar Paz-Y-Miño,
Ricardo Fujita, Francisco M Salzano,
Sandro L Bonatto,
Maria Cátira Bortolini,
Fabrício R Santos
[show abstract]
[hide abstract]
ABSTRACT: The human Y chromosome contains highly informative markers for making historical inferences about the pre-Columbian peopling of Americas. However, the scarcity of these markers has limited its use in the inference of shared ancestry and past migrations relevant to the origin of the culturally and biologically diverse Native Americans. To identify new single nucleotide polymorphisms (SNPs) and increase the phylogenetic resolution of the major haplogroup Q found in the Americas, we have performed a search for new polymorphisms based on sequencing divergent Y chromosomes identified by microsatellite haplotype analysis. Using this approach, a new Y-SNP (SA01) has been identified in the Andean populations of South America, allowing for the detection of a new sublineage of Q1a3a. This sublineage displays a less complex phylogeographic network of associated microsatellites and more restricted geographic occurrence, and is given the designation Q1a3a4. This result indicates that our approach can be successfully used to identify sublineages of interest in a specific region that allow the investigation of particular histories of human populations.
American Journal of Physical Anthropology 09/2011; 146(4):553-9. · 2.82 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Information on one Ecuadorian and three Peruvian Amerindian populations for 11 autosomal short tandem repeat (STR) loci is presented and incorporated in analyses that includes 26 other Native groups spread all over South America. Although in comparison with other studies we used a reduced number of markers, the number of populations included in our analyses is currently unmatched by any genome-wide dataset. The genetic polymorphisms indicate a clear division of the populations into three broad geographical areas: Andes, Amazonia, and the Southeast, which includes the Chaco and southern Brazil. The data also show good agreement with proposed hypotheses of splitting and dispersion of major language groups over the last 3,000 years. Therefore, relevant aspects of Native American history can be traced using as few as 11 STR autosomal markers coupled with a broad geographic distribution of sampled populations.
American Journal of Physical Anthropology 07/2011; 145(3):371-81. · 2.82 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This investigation was performed to identify and evaluate the distribution of all 15 Y-chromosome lineages belonging to the Q clade in a sample of natives from South America.
One hundred and forty-eight individuals from 20 Native American populations, as well as 24 Asian samples including Eskimos, were tested with 18 biallelic loci that can identify all currently known lineages of the Y-Chromosome Q clade. Sequencing was performed in part of the sample (∼180,000 nucleotides, which detected, for instance, several downstream markers related to the Q1a3a lineage).
No new mutation was found and Q1a3a was consistently found in high frequencies in all populations, followed at a much lower frequency by Q1a3*, while Q1a3a derived-lineages are probably population/tribe/region-specific.
The number of basal Y chromosome lineages in North America is apparently higher than in South America due probably to a bottleneck during the South American colonization and/or more recent Circum-Arctic gene flow.
American Journal of Human Biology 07/2011; 23(4):563-6. · 2.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We report X-chromosomal linkage disequilibrium (LD) patterns in Amerindian (Kogi, Wayuu, and Zenu) and admixed Latin American (Central Valley of Costa Rica and Southern Brazilian Gaucho) populations.
Short tandem repeats (STRs) widespread along the X-chromosome were investigated in 132 and 124 chromosomes sampled from the Amerindian tribes and the admixed Latin American populations, respectively. Diversity indexes (gene diversity and average numbers of alleles per locus) were estimated for each population and the level of LD was inferred with an exact test.
The Amerindian populations presented lower genetic diversity and a higher proportion of loci in LD than the admixed ones. Two haplotype blocks were identified in the X-chromosome, both restricted to the Amerindians. The first involved DXS8051 and DXS7108 in Xp22.22 and Xp22.3, while the second found only among the Kogi, included eight loci in a region between Xp11.4 and Xq21.1.
In accordance to previous work done with other populations, human isolates, such as Amerindian tribes, seem to be an optimal choice for the implementation of association studies due to the wide extent of LD which can be found in their gene pool. On the other hand, the low proportion of loci in LD found in both admixed populations studied here could be explained by events related to their history and similarities between the allele frequencies in the parental stocks.
American Journal of Human Biology 02/2011; 23(3):299-304. · 2.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A total of 172 persons from nine South Amerindian, three African and one Eskimo populations were studied in relation to the Paired box gene 9 (PAX9) exon 3 (138 base pairs) as well as its 5'and 3'flanking intronic segments (232 bp and 220 bp, respectively) and integrated with the information available for the same genetic region from individuals of different geographical origins. Nine mutations were scored in exon 3 and six in its flanking regions; four of them are new South American tribe-specific singletons. Exon3 nucleotide diversity is several orders of magnitude higher than its intronic regions. Additionally, a set of variants in the PAX9 and 101 other genes related with dentition can define at least some dental morphological differences between Sub-Saharan Africans and non-Africans, probably associated with adaptations after the modern human exodus from Africa. Exon 3 of PAX9 could be a good molecular example of how evolvability works.
PLoS ONE 01/2011; 6(1):e15656. · 4.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: One of the long-standing paradoxes in genomic evolution is the observation that much of the genome is composed of repetitive DNA which has been typically regarded as superfluous to the function of the genome in generating phenotypes. In this work, we used comparative phylogenetic approaches to investigate if the variations in genome sizes (GS) should be considered as adaptive or neutral processes by the comparison between GS and flower diameters (FD) of 50 Passiflora species, more specifically, within its two most species-rich subgenera, Passiflora and Decaloba. For this, we have constructed a phylogenetic tree of these species, estimated GS and FD of them, inferred the tempo and mode of evolution of these traits and their correlations, using both current and phylogenetically independent contrasted values. We found significant correlations among the traits, when considering the complete set of data or only the subgenus Passiflora, whereas no correlations were observed within Decaloba. Herein, we present convincing evidence of adaptive evolution of GS, as well as clues that this pattern is limited by a minimum genome size, which could reduce both the possibilities of changes in GS and the possibility of phenotypic responses to environment changes.
PLoS ONE 01/2011; 6(3):e18212. · 4.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The DRD4 variable number of tandem repeats (VNTR) allele distribution of 172 Guarani (Kaiowá and Ñandeva subgroups) and Kaingang Brazilian Amerindians is reported. These results are integrated with those previously obtained for this ethnic group. Allele frequencies for the three populations are within the interval observed for 15 other Native American populations and show intermediate values between those observed in Amazonia and Patagonia. Significant differences in allele distribution between recent past hunter-gatherer and agriculturalist populations are observed, with an increase of the 7R allele among hunter-gatherers (P < 0.001). Analysis of molecular variance (AMOVA) and pairwise F(ST) data suggest three distinct sectors for the genetic landscape of Native South America: Andes, Center/Southeast region, and Amazonia. Common traits among hunter-gatherers such as novelty-seeking temperament, hyperactivity, and impulsivity could have been important and advantageous in new environments during America's prehistoric colonization.
American Journal of Physical Anthropology 11/2010; 143(3):458-64. · 2.82 Impact Factor
