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Objectives: To investigate the variation in dental nonmetric traits and to evaluate the utility of this variation for inferring genetic ancestry proportions in a sample of admixed Latin Americans. Materials and Methods: We characterized a sample from Colombia (N = 477) for 34 dental traits and obtained estimates of individual Native American, European, and African ancestry using genome‐wide SNP data. We tested for correlation between dental traits, genetic ancestry, age, and sex. We carried out a biodistance analysis between the Colombian sample and reference continental population samples using the mean measure of divergence statistic calculated from dental trait frequencies. We evaluated the inference of genetic ancestry from dental traits using a regression approach (with 10‐fold cross‐validation) as well as by testing the correlation between estimates of ancestry obtained from genetic and dental data. Results: Latin Americans show intermediate dental trait frequencies when compared to Native Americans, Europeans, and Africans. Significant correlations were observed for several dental traits, genetic ancestry, age, and sex. The biodistance analysis displayed a closer relationship of Colombians to Europeans than to Native Americans and Africans. Mean ancestry estimates obtained from the dental data are similar to the genetic estimates (Native American: 32% vs. 28%, European: 59% vs. 63%, and African: 9% vs. 9%, respectively). However, dental features provided low predictive power for genetic ancestry of individuals in both approaches tested (R2 < 5% for all genetic ancestries across methods). Discussion: The frequency of dental traits in Latin Americans reflects their admixed Native American, European and African ancestry and can provide reasonable average estimates of genetic ancestry. However, the accuracy of individual genetic ancestry estimates is relatively low, probably influenced by the continental differentiation of dental traits, their genetic architecture, and the distribution of genetic ancestry in the individuals examined. [ABSTRACT FROM AUTHOR]

A total of 582 individuals (1,164 chromosomes) from two African, eight African-derived South American, five South American Amerindian, and three Brazilian urban populations were studied at four variable number of tandem repeat (VNTR) and two short tandem repeat (STR) hypervariable loci. These two sets of loci did not show distinct allele profiles, which might be expected if different processes promoted their molecular differentiation. The two African groups showed little difference between them, and their intrapopulational variation was similar to those obtained in the African-derived South American communities. The latter showed different degrees of interpopulation variability, despite the fact that they presented almost identical average degrees of non-African admixture. The [F.sub.ST] single locus estimates differed in the five sets of populations, probably due to genetic drift, indicating the need to consider population structure in the evaluation of their total variability. A high interpopulational diversity was found among Amerindian populations in relation to Brazilian African-derived isolated communities. This is probably a consequence of the differences in the patterns of gene flow and genetic drift that each of these semi-isolated groups experienced. KEY WORDS: DNA polymorphisms; South American blacks; Africans; genetic diversity; VNTR

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. Am. J. Hum. Biol., 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Presents information on a study which analyzed the intrapopulational gene diversities of two African and eight rural African-derived South American populations on the basis of six hypervariable repeat polymorphisms. Subjects and methods; Results; Discussion.

The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. 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 human face represents a combined set of highly heritable phenotypes, but knowledge on its genetic architecture remains limited, despite the relevance for various fields. A series of genome-wide association studies on 78 facial shape phenotypes quantified from 3-dimensional facial images of 10,115 Europeans identified 24 genetic loci reaching study-wide suggestive association (p < 5 × 10 -8 ), among which 17 were previously unreported. A follow-up multi-ethnic study in additional 7917 individuals confirmed 10 loci including six unreported ones (p adjusted < 2.1 × 10 -3 ). A global map of derived polygenic face scores assembled facial features in major continental groups consistent with anthropological knowledge. Analyses of epigenomic datasets from cranial neural crest cells revealed abundant cis -regulatory activities at the face-associated genetic loci. Luciferase reporter assays in neural crest progenitor cells highlighted enhancer activities of several face-associated DNA variants. These results substantially advance our understanding of the genetic basis underlying human facial variation and provide candidates for future in-vivo functional studies., Competing Interests: ZX, GD, LH, ML, PH, Md, GZ, KA, DL, YL, BP, EF, MM, JS, KM, SX, LJ, SW, Fd, BL, SR, AZ, SL, GS, LP, HT, RG, MB, SC, CG, GP, GB, FR, AU, MI, EW, SK, TN, RP, SB, SM, KT, AR, NM, TS, ES, SW, FL, MK No competing interests declared, (© 2019, Xiong et al.)

Shape variation of human head hair shows striking variation within and between human populations, while its genetic basis is far from being understood. We performed a series of genome-wide association studies (GWASs) and replication studies in a total of 28 964 subjects from 9 cohorts from multiple geographic origins. A meta-analysis of three European GWASs identified 8 novel loci (1p36.23 ERRFI1/SLC45A1, 1p36.22 PEX14, 1p36.13 PADI3, 2p13.3 TGFA, 11p14.1 LGR4, 12q13.13 HOXC13, 17q21.2 KRTAP, and 20q13.33 PTK6), and confirmed 4 previously known ones (1q21.3 TCHH/TCHHL1/LCE3E, 2q35 WNT10A, 4q21.21 FRAS1, and 10p14 LINC00708/GATA3), all showing genome-wide significant association with hair shape (P < 5e-8). All except one (1p36.22 PEX14) were replicated with nominal significance in at least one of the 6 additional cohorts of European, Native American and East Asian origins. Three additional previously known genes (EDAR, OFCC1, and PRSS53) were confirmed at the nominal significance level. A multivariable regression model revealed that 14 SNPs from different genes significantly and independently contribute to hair shape variation, reaching a cross-validated AUC value of 0.66 (95% CI: 0.62-0.70) and an AUC value of 0.64 in an independent validation cohort, providing an improved accuracy compared with a previous model. Prediction outcomes of 2504 individuals from a multiethnic sample were largely consistent with general knowledge on the global distribution of hair shape variation. Our study thus delivers target genes and DNA variants for future functional studies to further evaluate the molecular basis of hair shape in humans., (© The Author(s) 2017. Published by Oxford University Press.)