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1.
Commun Biol ; 7(1): 835, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982288

RESUMO

Significant progress has been made in the field of plant genomics, as demonstrated by the increased use of high-throughput methodologies that enable the characterization of multiple genome-wide molecular phenotypes. These findings have provided valuable insights into plant traits and their underlying genetic mechanisms, particularly in model plant species. Nonetheless, effectively leveraging them to make accurate predictions represents a critical step in crop genomic improvement. We present AgroNT, a foundational large language model trained on genomes from 48 plant species with a predominant focus on crop species. We show that AgroNT can obtain state-of-the-art predictions for regulatory annotations, promoter/terminator strength, tissue-specific gene expression, and prioritize functional variants. We conduct a large-scale in silico saturation mutagenesis analysis on cassava to evaluate the regulatory impact of over 10 million mutations and provide their predicted effects as a resource for variant characterization. Finally, we propose the use of the diverse datasets compiled here as the Plants Genomic Benchmark (PGB), providing a comprehensive benchmark for deep learning-based methods in plant genomic research. The pre-trained AgroNT model is publicly available on HuggingFace at https://huggingface.co/InstaDeepAI/agro-nucleotide-transformer-1b  for future research purposes.


Assuntos
Genoma de Planta , Plantas Comestíveis/genética , Genômica/métodos , Aprendizado Profundo , Manihot/genética
2.
Commun Biol ; 6(1): 958, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816865

RESUMO

The Nav1.7 voltage-gated sodium channel plays a key role in nociception. Three functional variants in the SCN9A gene (encoding M932L, V991L, and D1908G in Nav1.7), have recently been identified as stemming from Neanderthal introgression and to associate with pain symptomatology in UK BioBank data. In 1000 genomes data, these variants are absent in Europeans but common in Latin Americans. Analysing high-density genotype data from 7594 Latin Americans, we characterized Neanderthal introgression in SCN9A. We find that tracts of introgression occur on a Native American genomic background, have an average length of ~123 kb and overlap the M932L, V991L, and D1908G coding positions. Furthermore, we measured experimentally six pain thresholds in 1623 healthy Colombians. We found that Neanderthal ancestry in SCN9A is significantly associated with a lower mechanical pain threshold after sensitization with mustard oil and evidence of additivity of effects across Nav1.7 variants. Our findings support the reported association of Neanderthal Nav1.7 variants with clinical pain, define a specific sensory modality affected by archaic introgression in SCN9A and are consistent with independent effects of the Neanderthal variants on Nav1.7 function.


Assuntos
Homem de Neandertal , Limiar da Dor , Humanos , Animais , Homem de Neandertal/genética , Dor/genética , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Nociceptividade
3.
Nature ; 621(7977): 120-128, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37558883

RESUMO

Humans display substantial interindividual clinical variability after SARS-CoV-2 infection1-3, the genetic and immunological basis of which has begun to be deciphered4. However, the extent and drivers of population differences in immune responses to SARS-CoV-2 remain unclear. Here we report single-cell RNA-sequencing data for peripheral blood mononuclear cells-from 222 healthy donors of diverse ancestries-that were stimulated with SARS-CoV-2 or influenza A virus. We show that SARS-CoV-2 induces weaker, but more heterogeneous, interferon-stimulated gene activity compared with influenza A virus, and a unique pro-inflammatory signature in myeloid cells. Transcriptional responses to viruses display marked population differences, primarily driven by changes in cell abundance including increased lymphoid differentiation associated with latent cytomegalovirus infection. Expression quantitative trait loci and mediation analyses reveal a broad effect of cell composition on population disparities in immune responses, with genetic variants exerting a strong effect on specific loci. Furthermore, we show that natural selection has increased population differences in immune responses, particularly for variants associated with SARS-CoV-2 response in East Asians, and document the cellular and molecular mechanisms by which Neanderthal introgression has altered immune functions, such as the response of myeloid cells to viruses. Finally, colocalization and transcriptome-wide association analyses reveal an overlap between the genetic basis of immune responses to SARS-CoV-2 and COVID-19 severity, providing insights into the factors contributing to current disparities in COVID-19 risk.


Assuntos
COVID-19 , Genética Populacional , SARS-CoV-2 , Análise da Expressão Gênica de Célula Única , Animais , Humanos , Diferenciação Celular , COVID-19/genética , COVID-19/imunologia , COVID-19/virologia , Citomegalovirus/fisiologia , População do Leste Asiático/genética , Introgressão Genética , Vírus da Influenza A/patogenicidade , Vírus da Influenza A/fisiologia , Interferons/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Células Mieloides/imunologia , Homem de Neandertal/genética , Homem de Neandertal/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , SARS-CoV-2/fisiologia , Seleção Genética , Latência Viral
4.
Commun Biol ; 6(1): 481, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156940

RESUMO

We report a genome-wide association study of facial features in >6000 Latin Americans based on automatic landmarking of 2D portraits and testing for association with inter-landmark distances. We detected significant associations (P-value <5 × 10-8) at 42 genome regions, nine of which have been previously reported. In follow-up analyses, 26 of the 33 novel regions replicate in East Asians, Europeans, or Africans, and one mouse homologous region influences craniofacial morphology in mice. The novel region in 1q32.3 shows introgression from Neanderthals and we find that the introgressed tract increases nasal height (consistent with the differentiation between Neanderthals and modern humans). Novel regions include candidate genes and genome regulatory elements previously implicated in craniofacial development, and show preferential transcription in cranial neural crest cells. The automated approach used here should simplify the collection of large study samples from across the world, facilitating a cosmopolitan characterization of the genetics of facial features.


Assuntos
Homem de Neandertal , Humanos , Animais , Camundongos , Homem de Neandertal/genética , Estudo de Associação Genômica Ampla , Nariz , Diferenciação Celular
5.
Curr Biol ; 32(21): 4565-4575.e6, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36108636

RESUMO

The Vanuatu archipelago served as a gateway to Remote Oceania during one of the most extensive human migrations to uninhabited lands ∼3,000 years ago. Ancient DNA studies suggest an initial settlement by East Asian-related peoples that was quickly followed by the arrival of Papuan-related populations, leading to a major population turnover. Yet there is uncertainty over the population processes and the sociocultural factors that have shaped the genomic diversity of ni-Vanuatu, who present nowadays among the world's highest linguistic and cultural diversity. Here, we report new genome-wide data for 1,433 contemporary ni-Vanuatu from 29 different islands, including 287 couples. We find that ni-Vanuatu derive their East Asian- and Papuan-related ancestry from the same source populations and descend from relatively synchronous, sex-biased admixture events that occurred ∼1,700-2,300 years ago, indicating a peopling history common to the whole archipelago. However, East Asian-related ancestry proportions differ markedly across islands, suggesting that the Papuan-related population turnover was geographically uneven. Furthermore, we detect Polynesian ancestry arriving ∼600-1,000 years ago to Central and South Vanuatu in both Polynesian-speaking and non-Polynesian-speaking populations. Last, we provide evidence for a tendency of spouses to carry similar genetic ancestry, when accounting for relatedness avoidance. The signal is not driven by strong genetic effects of specific loci or trait-associated variants, suggesting that it results instead from social assortative mating. Altogether, our findings provide an insight into both the genetic history of ni-Vanuatu populations and how sociocultural processes have shaped the diversity of their genomes.


Assuntos
DNA Antigo , Migração Humana , Humanos , Genômica , Genoma Humano , Havaiano Nativo ou Outro Ilhéu do Pacífico , Genética Populacional
6.
Am J Hum Genet ; 109(6): 1117-1139, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35588731

RESUMO

Preeclampsia is a multi-organ complication of pregnancy characterized by sudden hypertension and proteinuria that is among the leading causes of preterm delivery and maternal morbidity and mortality worldwide. The heterogeneity of preeclampsia poses a challenge for understanding its etiology and molecular basis. Intriguingly, risk for the condition increases in high-altitude regions such as the Peruvian Andes. To investigate the genetic basis of preeclampsia in a population living at high altitude, we characterized genome-wide variation in a cohort of preeclamptic and healthy Andean families (n = 883) from Puno, Peru, a city located above 3,800 meters of altitude. Our study collected genomic DNA and medical records from case-control trios and duos in local hospital settings. We generated genotype data for 439,314 SNPs, determined global ancestry patterns, and mapped associations between genetic variants and preeclampsia phenotypes. A transmission disequilibrium test (TDT) revealed variants near genes of biological importance for placental and blood vessel function. The top candidate region was found on chromosome 13 of the fetal genome and contains clotting factor genes PROZ, F7, and F10. These findings provide supporting evidence that common genetic variants within coagulation genes play an important role in preeclampsia. A selection scan revealed a potential adaptive signal around the ADAM12 locus on chromosome 10, implicated in pregnancy disorders. Our discovery of an association in a functional pathway relevant to pregnancy physiology in an understudied population of Native American origin demonstrates the increased power of family-based study design and underscores the importance of conducting genetic research in diverse populations.


Assuntos
Pré-Eclâmpsia , Altitude , Fatores de Coagulação Sanguínea , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Fator VII/genética , Fator X/genética , Feminino , Humanos , Peru/epidemiologia , Placenta , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/genética , Gravidez
7.
Mol Biol Evol ; 39(4)2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35460423

RESUMO

Throughout human evolutionary history, large-scale migrations have led to intermixing (i.e., admixture) between previously separated human groups. Although classical and recent work have shown that studying admixture can yield novel historical insights, the extent to which this process contributed to adaptation remains underexplored. Here, we introduce a novel statistical model, specific to admixed populations, that identifies loci under selection while determining whether the selection likely occurred post-admixture or prior to admixture in one of the ancestral source populations. Through extensive simulations, we show that this method is able to detect selection, even in recently formed admixed populations, and to accurately differentiate between selection occurring in the ancestral or admixed population. We apply this method to genome-wide SNP data of ∼4,000 individuals in five admixed Latin American cohorts from Brazil, Chile, Colombia, Mexico, and Peru. Our approach replicates previous reports of selection in the human leukocyte antigen region that are consistent with selection post-admixture. We also report novel signals of selection in genomic regions spanning 47 genes, reinforcing many of these signals with an alternative, commonly used local-ancestry-inference approach. These signals include several genes involved in immunity, which may reflect responses to endemic pathogens of the Americas and to the challenge of infectious disease brought by European contact. In addition, some of the strongest signals inferred to be under selection in the Native American ancestral groups of modern Latin Americans overlap with genes implicated in energy metabolism phenotypes, plausibly reflecting adaptations to novel dietary sources available in the Americas.


Assuntos
Genética Populacional , Genoma Humano , Genômica/métodos , Hispânico ou Latino/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética
8.
Nature ; 592(7855): 583-589, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33854233

RESUMO

The Pacific region is of major importance for addressing questions regarding human dispersals, interactions with archaic hominins and natural selection processes1. However, the demographic and adaptive history of Oceanian populations remains largely uncharacterized. Here we report high-coverage genomes of 317 individuals from 20 populations from the Pacific region. We find that the ancestors of Papuan-related ('Near Oceanian') groups underwent a strong bottleneck before the settlement of the region, and separated around 20,000-40,000 years ago. We infer that the East Asian ancestors of Pacific populations may have diverged from Taiwanese Indigenous peoples before the Neolithic expansion, which is thought to have started from Taiwan around 5,000 years ago2-4. Additionally, this dispersal was not followed by an immediate, single admixture event with Near Oceanian populations, but involved recurrent episodes of genetic interactions. Our analyses reveal marked differences in the proportion and nature of Denisovan heritage among Pacific groups, suggesting that independent interbreeding with highly structured archaic populations occurred. Furthermore, whereas introgression of Neanderthal genetic information facilitated the adaptation of modern humans related to multiple phenotypes (for example, metabolism, pigmentation and neuronal development), Denisovan introgression was primarily beneficial for immune-related functions. Finally, we report evidence of selective sweeps and polygenic adaptation associated with pathogen exposure and lipid metabolism in the Pacific region, increasing our understanding of the mechanisms of biological adaptation to island environments.


Assuntos
Adaptação Biológica/genética , Evolução Biológica , Genética Populacional , Genoma Humano/genética , Genômica , Migração Humana/história , Ilhas , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Animais , Austrália , Conjuntos de Dados como Assunto , Ásia Oriental , Introgressão Genética , História Antiga , Humanos , Homem de Neandertal/genética , Oceania , Oceano Pacífico , Taiwan
9.
Forensic Sci Int Genet ; 53: 102517, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33865096

RESUMO

Here we evaluate the accuracy of prediction for eye, hair and skin pigmentation in a dataset of > 6500 individuals from Mexico, Colombia, Peru, Chile and Brazil (including genome-wide SNP data and quantitative/categorical pigmentation phenotypes - the CANDELA dataset CAN). We evaluated accuracy in relation to different analytical methods and various phenotypic predictors. As expected from statistical principles, we observe that quantitative traits are more sensitive to changes in the prediction models than categorical traits. We find that Random Forest or Linear Regression are generally the best performing methods. We also compare the prediction accuracy of SNP sets defined in the CAN dataset (including 56, 101 and 120 SNPs for eye, hair and skin colour prediction, respectively) to the well-established HIrisPlex-S SNP set (including 6, 22 and 36 SNPs for eye, hair and skin colour prediction respectively). When training prediction models on the CAN data, we observe remarkably similar performances for HIrisPlex-S and the larger CAN SNP sets for the prediction of hair (categorical) and eye (both categorical and quantitative), while the CAN sets outperform HIrisPlex-S for quantitative, but not for categorical skin pigmentation prediction. The performance of HIrisPlex-S, when models are trained in a world-wide sample (although consisting of 80% Europeans, https://hirisplex.erasmusmc.nl), is lower relative to training in the CAN data (particularly for hair and skin colour). Altogether, our observations are consistent with common variation of eye and hair colour having a relatively simple genetic architecture, which is well captured by HIrisPlex-S, even in admixed Latin Americans (with partial European ancestry). By contrast, since skin pigmentation is a more polygenic trait, accuracy is more sensitive to prediction SNP set size, although here this effect was only apparent for a quantitative measure of skin pigmentation. Our results support the use of HIrisPlex-S in the prediction of categorical pigmentation traits for forensic purposes in Latin America, while illustrating the impact of training datasets on its accuracy.


Assuntos
Cor de Olho/genética , Cor de Cabelo/genética , Polimorfismo de Nucleotídeo Único , Pigmentação da Pele/genética , Conjuntos de Dados como Assunto , Genética Populacional , Genótipo , Humanos , América Latina , Modelos Logísticos , Fenótipo
10.
Sci Adv ; 7(6)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33547071

RESUMO

To characterize the genetic basis of facial features in Latin Americans, we performed a genome-wide association study (GWAS) of more than 6000 individuals using 59 landmark-based measurements from two-dimensional profile photographs and ~9,000,000 genotyped or imputed single-nucleotide polymorphisms. We detected significant association of 32 traits with at least 1 (and up to 6) of 32 different genomic regions, more than doubling the number of robustly associated face morphology loci reported until now (from 11 to 23). These GWAS hits are strongly enriched in regulatory sequences active specifically during craniofacial development. The associated region in 1p12 includes a tract of archaic adaptive introgression, with a Denisovan haplotype common in Native Americans affecting particularly lip thickness. Among the nine previously unidentified face morphology loci we identified is the VPS13B gene region, and we show that variants in this region also affect midfacial morphology in mice.


Assuntos
Face , Polimorfismo de Nucleotídeo Único , Proteínas de Transporte Vesicular , Animais , Face/anatomia & histologia , Estudo de Associação Genômica Ampla , Genótipo , Hispânico ou Latino/genética , Humanos , Camundongos , Fenótipo , Proteínas de Transporte Vesicular/genética
11.
Nat Commun ; 10(1): 358, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30664655

RESUMO

We report a genome-wide association scan in >6,000 Latin Americans for pigmentation of skin and eyes. We found eighteen signals of association at twelve genomic regions. These include one novel locus for skin pigmentation (in 10q26) and three novel loci for eye pigmentation (in 1q32, 20q13 and 22q12). We demonstrate the presence of multiple independent signals of association in the 11q14 and 15q13 regions (comprising the GRM5/TYR and HERC2/OCA2 genes, respectively) and several epistatic interactions among independently associated alleles. Strongest association with skin pigmentation at 19p13 was observed for an Y182H missense variant (common only in East Asians and Native Americans) in MFSD12, a gene recently associated with skin pigmentation in Africans. We show that the frequency of the derived allele at Y182H is significantly correlated with lower solar radiation intensity in East Asia and infer that MFSD12 was under selection in East Asians, probably after their split from Europeans.


Assuntos
Epistasia Genética , Cor de Olho/genética , Genoma Humano , Locos de Características Quantitativas , Pigmentação da Pele/genética , Alelos , Povo Asiático , Evolução Biológica , Etnicidade , Feminino , Expressão Gênica , Frequência do Gene , Genética Populacional , Estudo de Associação Genômica Ampla , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , América Latina , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Polimorfismo de Nucleotídeo Único , Receptor de Glutamato Metabotrópico 5/genética , Ubiquitina-Proteína Ligases , População Branca
12.
Ann Hum Genet ; 83(1): 11-22, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30264486

RESUMO

The genetic trait of lactase persistence (LP) evolved as an adaptation to milking pastoralism in the Old World and is a well-known example of positive natural selection in humans. However, the specific mechanisms conferring this selective advantage are unknown. To understand the relationship between milk drinking, LP, growth, reproduction, and survival, communities of the Coquimbo Region in Chile, with recent adoption of milking agropastoralism, were used as a model population. DNA samples and data on stature, reproduction, and diet were collected from 451 participants. Lactose tolerance tests were done on 41 of them. The European -13,910*T (rs4988235) was the only LP causative variant found, showing strong association (99.6%) with LP phenotype. Models of associations of inferred LP status and milk consumption, with fertility, mortality, height, and weight were adjusted with measures of ancestry and relatedness to control for population structure. Although we found no statistically significant effect of LP on fertility, a significant effect (P = 0.002) was observed of LP on body mass index (BMI) in males and of BMI on fertility (P = 0.003). These results fail to support a causal relationship between LP and fertility yet suggest the idea of a nutritional advantage of LP. Furthermore, the proportion of European ancestry around the genetic region of -13,910*T is significantly higher (P = 0.008) than the proportion of European ancestry genome-wide, providing evidence of recent positive selection since European-Amerindian admixture. This signature was absent in nonpastoralist Latin American populations, supporting the hypothesis of specific adaptation to milking agropastoralism in the Coquimbo communities.


Assuntos
Agricultura , Etnicidade/genética , Evolução Molecular , Lactase/genética , Animais , Índice de Massa Corporal , Chile , Feminino , Fertilidade , Frequência do Gene , Estudos de Associação Genética , Cabras , Haplótipos , Humanos , Intolerância à Lactose/genética , Masculino , Leite , Fenômenos Fisiológicos da Nutrição , Fenótipo , Polimorfismo de Nucleotídeo Único
13.
Proc Natl Acad Sci U S A ; 116(2): 593-598, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30584109

RESUMO

Few phenomena have had as profound or long-lasting consequences in human history as the emergence of large-scale centralized states in the place of smaller scale and more local societies. This study examines a fundamental, and yet unexplored, consequence of state formation: its genetic legacy. We studied the genetic impact of state centralization during the formation of the eminent precolonial Kuba Kingdom of the Democratic Republic of the Congo (DRC) in the 17th century. We analyzed genome-wide data from over 690 individuals sampled from 27 different ethnic groups from the Kasai Central Province of the DRC. By comparing genetic patterns in the present-day Kuba, whose ancestors were part of the Kuba Kingdom, with those in neighboring non-Kuba groups, we show that the Kuba today are more genetically diverse and more similar to other groups in the region than expected, consistent with the historical unification of distinct subgroups during state centralization. We also found evidence of genetic mixing dating to the time of the Kingdom at its most prominent. Using this unique dataset, we characterize the genetic history of the Kasai Central Province and describe the historic late wave of migrations into the region that contributed to a Bantu-like ancestry component found across large parts of Africa today. Taken together, we show the power of genetics to evidence events of sociopolitical importance and highlight how DNA can be used to better understand the behaviors of both people and institutions in the past.


Assuntos
Fluxo Gênico , Genética Humana , Modelos Genéticos , República Democrática do Congo , Feminino , Humanos , Masculino
14.
Nat Commun ; 9(1): 5388, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30568240

RESUMO

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.


Assuntos
Migração Humana , Indígenas Norte-Americanos/genética , Indígenas Sul-Americanos/genética , Haplótipos , Humanos , México , Nariz/anatomia & histologia , América do Sul
15.
Annu Rev Genomics Hum Genet ; 18: 277-296, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28859572

RESUMO

The history of the Americas involved the encounter of millions of Native Americans, Europeans, and Africans. A variable admixture of these three continental groups has taken place throughout the continent, influenced by demography and a range of social factors. This variable admixture has had a major influence on the genetic makeup of populations across the continent. Here, we summarize the demographic history of the region, highlight some social factors that affected historical admixture, and review major patterns of ancestry across the Western Hemisphere based on genetic data.


Assuntos
Demografia , Variação Genética , Genética Populacional , Indígena Americano ou Nativo do Alasca/genética , América , População Negra/genética , Feminino , Humanos , Masculino , População Branca/genética
16.
Mol Biol Evol ; 34(2): 318-329, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27744413

RESUMO

North Africa is characterized by its diverse cultural and linguistic groups and its genetic heterogeneity. Genomic data has shown an amalgam of components mixed since pre-Holocean times. Though no differences have been found in uniparental and classical markers between Berbers and Arabs, the two main ethnic groups in the region, the scanty genomic data available have highlighted the singularity of Berbers. We characterize the genetic heterogeneity of North African groups, focusing on the putative differences of Berbers and Arabs, and estimate migration dates. We analyze genome-wide autosomal data in five Berber and six Arab groups, and compare them to Middle Easterns, sub-Saharans, and Europeans. Haplotype-based methods show a lack of correlation between geographical and genetic populations, and a high degree of genetic heterogeneity, without strong differences between Berbers and Arabs. Berbers enclose genetically diverse groups, from isolated endogamous groups with high autochthonous component frequencies, large homozygosity runs and low effective population sizes, to admixed groups with high frequencies of sub-Saharan and Middle Eastern components. Admixture time estimates show a complex pattern of recent historical migrations, with a peak around the 7th century C.E. coincident with the Arabization of the region; sub-Saharan migrations since the 1st century B.C. in agreement with Roman slave trade; and a strong migration in the 17th century C.E., coincident with a huge impact of the trans-Atlantic and trans-Saharan trade of sub-Saharan slaves in the Modern Era. The genetic complexity found should be taken into account when selecting reference groups in population genetics and biomedical studies.


Assuntos
Árabes/genética , População Negra/genética , Pool Gênico , África do Norte , DNA Mitocondrial/genética , Frequência do Gene , Variação Genética , Genética Populacional , Haplótipos , Migração Humana , Humanos , Polimorfismo de Nucleotídeo Único , População Branca/genética
17.
Curr Opin Genet Dev ; 41: 106-114, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27690355

RESUMO

Latin Americans arguably represent the largest recently admixed populations in the world. This reflects a history of massive settlement by immigrants (mostly Europeans and Africans) and their variable admixture with Natives, starting in 1492. This process resulted in the population of Latin America showing an extensive genetic and phenotypic diversity. Here we review how genetic analyses are being applied to examine the demographic history of this population, including patterns of mating, population structure and ancestry. The admixture history of Latin America, and the resulting extensive diversity of the region, represents a natural experiment offering an advantageous setting for genetic association studies. We review how recent analyses in Latin Americans are contributing to elucidating the genetic architecture of human complex traits.


Assuntos
População Negra/genética , Genética Populacional/história , Migração Humana/história , População Branca/genética , Genoma Humano , História do Século XV , História do Século XVI , Humanos , América Latina
18.
Nat Commun ; 7: 11616, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27193062

RESUMO

We report a genome-wide association scan for facial features in ∼6,000 Latin Americans. We evaluated 14 traits on an ordinal scale and found significant association (P values<5 × 10(-8)) at single-nucleotide polymorphisms (SNPs) in four genomic regions for three nose-related traits: columella inclination (4q31), nose bridge breadth (6p21) and nose wing breadth (7p13 and 20p11). In a subsample of ∼3,000 individuals we obtained quantitative traits related to 9 of the ordinal phenotypes and, also, a measure of nasion position. Quantitative analyses confirmed the ordinal-based associations, identified SNPs in 2q12 associated to chin protrusion, and replicated the reported association of nasion position with SNPs in PAX3. Strongest association in 2q12, 4q31, 6p21 and 7p13 was observed for SNPs in the EDAR, DCHS2, RUNX2 and GLI3 genes, respectively. Associated SNPs in 20p11 extend to PAX1. Consistent with the effect of EDAR on chin protrusion, we documented alterations of mandible length in mice with modified Edar funtion.


Assuntos
Proteínas Relacionadas a Caderinas/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Receptor Edar/genética , Face/anatomia & histologia , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição Box Pareados/genética , Proteína Gli3 com Dedos de Zinco/genética , Adulto , Variação Anatômica , Animais , Estudo de Associação Genômica Ampla , Humanos , América Latina , Desenvolvimento Maxilofacial/genética , Camundongos , Polimorfismo de Nucleotídeo Único , Adulto Jovem
19.
Nat Commun ; 7: 10815, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26926045

RESUMO

We report a genome-wide association scan in over 6,000 Latin Americans for features of scalp hair (shape, colour, greying, balding) and facial hair (beard thickness, monobrow, eyebrow thickness). We found 18 signals of association reaching genome-wide significance (P values 5 × 10(-8) to 3 × 10(-119)), including 10 novel associations. These include novel loci for scalp hair shape and balding, and the first reported loci for hair greying, monobrow, eyebrow and beard thickness. A newly identified locus influencing hair shape includes a Q30R substitution in the Protease Serine S1 family member 53 (PRSS53). We demonstrate that this enzyme is highly expressed in the hair follicle, especially the inner root sheath, and that the Q30R substitution affects enzyme processing and secretion. The genome regions associated with hair features are enriched for signals of selection, consistent with proposals regarding the evolution of human hair.


Assuntos
Face/fisiologia , Regulação da Expressão Gênica/fisiologia , Estudo de Associação Genômica Ampla , Cabelo/crescimento & desenvolvimento , Grupos Raciais , Couro Cabeludo/fisiologia , Feminino , Variação Genética , Humanos , Masculino
20.
PLoS Genet ; 10(5): e1004353, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24809476

RESUMO

Genome sequencing of the 5,300-year-old mummy of the Tyrolean Iceman, found in 1991 on a glacier near the border of Italy and Austria, has yielded new insights into his origin and relationship to modern European populations. A key finding of that study was an apparent recent common ancestry with individuals from Sardinia, based largely on the Y chromosome haplogroup and common autosomal SNP variation. Here, we compiled and analyzed genomic datasets from both modern and ancient Europeans, including genome sequence data from over 400 Sardinians and two ancient Thracians from Bulgaria, to investigate this result in greater detail and determine its implications for the genetic structure of Neolithic Europe. Using whole-genome sequencing data, we confirm that the Iceman is, indeed, most closely related to Sardinians. Furthermore, we show that this relationship extends to other individuals from cultural contexts associated with the spread of agriculture during the Neolithic transition, in contrast to individuals from a hunter-gatherer context. We hypothesize that this genetic affinity of ancient samples from different parts of Europe with Sardinians represents a common genetic component that was geographically widespread across Europe during the Neolithic, likely related to migrations and population expansions associated with the spread of agriculture.


Assuntos
Fósseis , Genética Populacional , Genoma Humano , Europa (Continente) , Feminino , Humanos , Polimorfismo de Nucleotídeo Único
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