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1.
Gene ; 776: 145351, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333226

RESUMO

Resolving the temporal community composition of a larvae population can not only further our understanding of the regional species composition but also help us to infer the reproductive times of regional fish taxa, which can have implications on the development of effective monitoring and conservation policies for the regional fish stock. Nevertheless, correctly diagnosing the fish larvae is extremely challenging due to the paucity of diagnostic morphological characters at the species level. Based on daily larval samplings during March and October in 2018, this study combined morphological features with a DNA barcode technique to determine the species composition of fish larvae in the lower Pearl River drainage (LPR) and evaluate the spawning periods of identified species. Due to an absence of reference barcodes for LPR fishes, a DNA barcode library of adult fishes in the LPR was built for 384 individuals representing 78 morphological species. Analyses demonstrated the usability of the barcode library and uncovered many undetected mitochondrial lineages in 12 species. Morphological analyses performed on 81 temporal larval samples revealed 25 morphotypes and assigned 9 morphotypes into the species level. A total of 1624 larvae from 96 temporal larval samples were selected for molecular identification, and high quality barcoding sequences were obtained from 1391 larvae. We accurately assigned 1078 larvae to 37 species using our barcode library and published database. Among the identified species, a critically endangered species, namely, Ochetobius elongatus, and several invasive species were examined, providing a new perspective to assess the stock of regional endangered and invasive species. Furthermore, this study found high species diversity occurred primarily between May and September, and clarified the spawning periods of identified species inferred from the temporal occurrences of larvae. Above all, our study highlights the applicability to fish larval ecology to assist conservation and fishery management efforts.


Assuntos
Aquicultura/métodos , Peixes/genética , Larva/genética , Animais , China , Código de Barras de DNA Taxonômico/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genética Populacional/métodos , Filogenia , Reprodução/genética , Reprodução/fisiologia , Rios , Especificidade da Espécie
2.
Nat Genet ; 52(9): 898-907, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879509

RESUMO

Most cancer genomic data are generated from bulk samples composed of mixtures of cancer subpopulations, as well as normal cells. Subclonal reconstruction methods based on machine learning aim to separate those subpopulations in a sample and infer their evolutionary history. However, current approaches are entirely data driven and agnostic to evolutionary theory. We demonstrate that systematic errors occur in the analysis if evolution is not accounted for, and this is exacerbated with multi-sampling of the same tumor. We present a novel approach for model-based tumor subclonal reconstruction, called MOBSTER, which combines machine learning with theoretical population genetics. Using public whole-genome sequencing data from 2,606 samples from different cohorts, new data and synthetic validation, we show that this method is more robust and accurate than current techniques in single-sample, multiregion and longitudinal data. This approach minimizes the confounding factors of nonevolutionary methods, thus leading to more accurate recovery of the evolutionary history of human cancers.


Assuntos
Neoplasias/genética , Evolução Clonal/genética , Genética Populacional/métodos , Genômica/métodos , Humanos , Aprendizado de Máquina , Sequenciamento Completo do Genoma/métodos
3.
PLoS One ; 15(9): e0238984, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966312

RESUMO

Garcinia kola (Heckel) is a versatile tree indigenous to West and Central Africa. All parts of the tree have value in traditional medicine. Natural populations of the species have declined over the years due to overexploitation. Assessment of genetic diversity and population structure of G. kola is important for its management and conservation. The present study investigates the genetic diversity and population structure of G. kola populations in Benin using ultra-high-throughput diversity array technology (DArT) single nucleotide polymorphism (SNP) markers. From the 102 accessions sampled, two were excluded from the final dataset owing to poor genotyping coverage. A total of 43,736 SNPs were reported, of which 12,585 were used for analyses after screening with quality control parameters including Minor allele frequency (≥ 0.05), call rate (≥ 80%), reproducibility (≥ 95%), and polymorphic information content (≥ 1%). Analysis revealed low genetic diversity with expected heterozygosity per population ranging from 0.196 to 0.228. Pairwise F-statistics (FST) revealed low levels of genetic differentiation between populations while an Analysis of molecular variance (AMOVA) indicated that the majority of variation (97.86%) was within populations. Population structure analysis through clustering and discriminant analysis on principal component revealed two admixed clusters, implying little genetic structure. However, the model-based maximum likelihood in Admixture indicated only one genetic cluster. The present study indicated low genetic diversity of G. kola, and interventions are needed to be tailored towards its conservation.


Assuntos
Garcinia kola/genética , Alelos , Benin , Frequência do Gene/genética , Variação Genética/genética , Genética Populacional/métodos , Genoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
4.
PLoS One ; 15(9): e0239734, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986762

RESUMO

Phedimus takesimensis (Ulleungdo flat-leaved stonecrop) is endemic to Ulleung and Dokdo Islands off the east coast of the Korean Peninsula. It was suggested that P. takesimensis originated via anagenetic speciation from the continental progenitor species P. kamtchaticus or P. aizoon. However, little is known of the phylogenetic relationships and population genetic structure among species of Phedimus in the Korean Peninsula and Ulleung/Dokdo Islands. We inferred the phylogenetic relationships among congeneric species in Korea based on nuclear ribosomal DNA internal transcribed spacer and chloroplast noncoding regions. We also sampled extensively for P. takesimensis on Ulleung Island and the continental species, P. kamtschaticus and P. aizoon, to assess the genetic consequences of anagenetic speciation. We found (1) the monophyly of P. takesimensis, (2) no apparent reduction in genetic diversity in anagenetically derived P. takesimensis compared to the continental progenitor species, (3) apparent population genetic structuring of P. takesimensis, and (4) two separate colonization events for the origin of the Dokdo Island population. This study contributes to our understanding of the genetic consequences of anagenetic speciation on Ulleung Island.


Assuntos
Crassulaceae/genética , DNA de Cloroplastos/genética , Evolução Molecular , Especiação Genética , Filogenia , Sequência de Bases , DNA de Cloroplastos/isolamento & purificação , DNA Espaçador Ribossômico/genética , Variação Genética , Genética Populacional/métodos , Ilhas , República da Coreia , Análise de Sequência de DNA
5.
Proc Natl Acad Sci U S A ; 117(37): 22805-22814, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32839345

RESUMO

A Cas9/guide RNA-based gene drive strain, AgNosCd-1, was developed to deliver antiparasite effector molecules to the malaria vector mosquito, Anopheles gambiae The drive system targets the cardinal gene ortholog producing a red-eye phenotype. Drive can achieve 98 to 100% in both sexes and full introduction was observed in small cage trials within 6 to 10 generations following a single release of gene-drive males. No genetic load resulting from the integrated transgenes impaired drive performance in the trials. Potential drive-resistant target-site alleles arise at a frequency <0.1, and five of the most prevalent polymorphisms in the guide RNA target site in collections of colonized and wild-derived African mosquitoes do not prevent cleavage in vitro by the Cas9/guide RNA complex. Only one predicted off-target site is cleavable in vitro, with negligible deletions observed in vivo. AgNosCd-1 meets key performance criteria of a target product profile and can be a valuable component of a field-ready strain for mosquito population modification to control malaria transmission.


Assuntos
Anopheles/genética , Tecnologia de Impulso Genético/métodos , Controle de Mosquitos/métodos , Alelos , Animais , Animais Geneticamente Modificados/genética , Sistemas CRISPR-Cas/genética , Genética Populacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Malária/prevenção & controle , Mosquitos Vetores/genética , Fenótipo , Transgenes/genética
6.
Leg Med (Tokyo) ; 47: 101738, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32818903

RESUMO

Genetic markers on the Y chromosome, including short tandem repeats (Y-STRs) and single nucleotide polymorphisms (Y-SNPs), are used widely in forensic genetics. Both Y-STR-based haplotypes and Y-SNP-based haplogroups provide information on a population's genetic structure, which is useful for the identification of individuals. However, there are few studies on these two types of genetic markers in the various Chinese populations. In this study, 284 Han individuals from four prefecture-level cities in Shandong Province (Binzhou, Dezhou, Heze, and Weihai) were genotyped by 29 Y-STRs (from our previous study) and 213 Y-SNPs (self-designed for the Haplogroup O2 Y-SNP panel). Haplogroup O was the most predominant among the four cities. The highest haplogroup diversity (0.9745) was observed in the Heze population, with a discrimination capacity (DC) value of 0.5625. The haplotype diversity and DC values of the Binzhou and Heze populations were 1.0000. Furthermore, genetic differences were observed between the coastal and inland cities; the results of their statistical analysis are presented herein.


Assuntos
Cromossomos Humanos Y/genética , Grupos Étnicos/genética , Genética Populacional/métodos , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único , China/etnologia , Feminino , Genótipo , Haplótipos/genética , Humanos , Masculino
7.
Am J Hum Genet ; 107(3): 461-472, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32781045

RESUMO

RNA sequencing (RNA-seq) is a powerful technology for studying human transcriptome variation. We introduce PAIRADISE (Paired Replicate Analysis of Allelic Differential Splicing Events), a method for detecting allele-specific alternative splicing (ASAS) from RNA-seq data. Unlike conventional approaches that detect ASAS events one sample at a time, PAIRADISE aggregates ASAS signals across multiple individuals in a population. By treating the two alleles of an individual as paired, and multiple individuals sharing a heterozygous SNP as replicates, we formulate ASAS detection using PAIRADISE as a statistical problem for identifying differential alternative splicing from RNA-seq data with paired replicates. PAIRADISE outperforms alternative statistical models in simulation studies. Applying PAIRADISE to replicate RNA-seq data of a single individual and to population-scale RNA-seq data across many individuals, we detect ASAS events associated with genome-wide association study (GWAS) signals of complex traits or diseases. Additionally, PAIRADISE ASAS analysis detects the effects of rare variants on alternative splicing. PAIRADISE provides a useful computational tool for elucidating the genetic variation and phenotypic association of alternative splicing in populations.


Assuntos
Processamento Alternativo/genética , Predisposição Genética para Doença , Herança Multifatorial/genética , Transcriptoma/genética , Alelos , Feminino , Perfilação da Expressão Gênica , Genética Populacional/métodos , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Modelos Estatísticos , RNA-Seq , Sequenciamento Completo do Exoma
8.
Proc Natl Acad Sci U S A ; 117(34): 20672-20680, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32817464

RESUMO

Rapid phenotypic adaptation is often observed in natural populations and selection experiments. However, detecting the genome-wide impact of this selection is difficult since adaptation often proceeds from standing variation and selection on polygenic traits, both of which may leave faint genomic signals indistinguishable from a noisy background of genetic drift. One promising signal comes from the genome-wide covariance between allele frequency changes observable from temporal genomic data (e.g., evolve-and-resequence studies). These temporal covariances reflect how heritable fitness variation in the population leads changes in allele frequencies at one time point to be predictive of the changes at later time points, as alleles are indirectly selected due to remaining associations with selected alleles. Since genetic drift does not lead to temporal covariance, we can use these covariances to estimate what fraction of the variation in allele frequency change through time is driven by linked selection. Here, we reanalyze three selection experiments to quantify the effects of linked selection over short timescales using covariance among time points and across replicates. We estimate that at least 17 to 37% of allele frequency change is driven by selection in these experiments. Against this background of positive genome-wide temporal covariances, we also identify signals of negative temporal covariance corresponding to reversals in the direction of selection for a reasonable proportion of loci over the time course of a selection experiment. Overall, we find that in the three studies we analyzed, linked selection has a large impact on short-term allele frequency dynamics that is readily distinguishable from genetic drift.


Assuntos
Adaptação Biológica/genética , Frequência do Gene/genética , Seleção Genética/genética , Aclimatação/genética , Adaptação Fisiológica/genética , Alelos , Animais , Evolução Biológica , Evolução Molecular , Frequência do Gene/fisiologia , Deriva Genética , Genética Populacional/métodos , Genômica/métodos , Humanos , Modelos Genéticos , Herança Multifatorial/genética , Densidade Demográfica
9.
Hum Biol ; 91(4): 249-256, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767895

RESUMO

Tacuarembó is a department located in northeastern Uruguay, whose population is the result of several migration waves from Europe and Near East, as well as Africans and Afro-descents mostly from Brazil; these waves settled with the territory's various Native ethnic groups (Charrúa, Minuán, and Guaraní). In the past, this population has been the focus of genetic studies showing this trihybrid origin, with greater contributions of Natives and Africans than in other Uruguayan regions. In this study we analyzed eight Alu insertions (A25, ACE, APOA1, B65, D1, F13B, PV92, TPA25) to provide valuable information for ancestrality and genetic differentiation and to compare with both previous studies on the Tacuarembó population and Alu frequencies in other Uruguayan populations. The European contribution to Alu and classical markers was almost equal to that of a previous study using 22 classical markers (63% vs. 65%), while African contribution was higher (30% vs. 15%), and Native American contribution shows an important difference in Alu: 7% versus 20%. We found no significant differences in genetic differentiation between Tacuarembó and Montevideo but significant differences between Tacuarembó and Basque descendants from Trinidad. Our results support previous findings obtained with classical markers that demonstrate the trihybrid composition of the Tacuarembó population, correlated with historical records. Thus, Alu insertions provide interesting information in light of the admixture process in the Uruguayan population.


Assuntos
Elementos Alu/genética , Grupos Étnicos/genética , Testes Genéticos/métodos , Brasil/etnologia , Europa (Continente)/etnologia , Feminino , Frequência do Gene , Variação Genética , Genética Populacional/métodos , Humanos , Masculino , Oriente Médio/etnologia , Grupos Populacionais/genética , Espanha/etnologia , Uruguai/etnologia
10.
Hum Biol ; 91(4): 257-277, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767896

RESUMO

The Fujian Tanka people are officially classified as a southern Han ethnic group, whereas they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: (1) the Han Chinese origin, (2) the ancient Daic origin, (3) and the admixture between Daic and Han. This study addressed this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. The southern East Asian predominant haplogroups (e.g., Y-chromosome O1a1a-P203 and O1b1a1a-M95, and mtDNA F2a, M7c1, and F1a1) had relatively high frequencies in Tanka. The interpopulation comparison revealed that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages but are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song dynasty), indicating that they are an indigenous population, not late Daic migrants from southwestern China.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional/métodos , Grupo com Ancestrais do Continente Asiático/genética , China/etnologia , DNA Mitocondrial/história , Grupos Étnicos/genética , Feminino , Testes Genéticos/métodos , Haplótipos/genética , História Antiga , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
11.
PLoS Comput Biol ; 16(8): e1008065, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797037

RESUMO

Inference of admixture proportions is a classical statistical problem in population genetics. Standard methods implicitly assume that both parents of an individual have the same admixture fraction. However, this is rarely the case in real data. In this paper we show that the distribution of admixture tract lengths in a genome contains information about the admixture proportions of the ancestors of an individual. We develop a Hidden Markov Model (HMM) framework for estimating the admixture proportions of the immediate ancestors of an individual, i.e. a type of decomposition of an individual's admixture proportions into further subsets of ancestral proportions in the ancestors. Based on a genealogical model for admixture tracts, we develop an efficient algorithm for computing the sampling probability of the genome from a single individual, as a function of the admixture proportions of the ancestors of this individual. This allows us to perform probabilistic inference of admixture proportions of ancestors only using the genome of an extant individual. We perform extensive simulations to quantify the error in the estimation of ancestral admixture proportions under various conditions. To illustrate the utility of the method, we apply it to real genetic data.


Assuntos
Genética Populacional/métodos , Avós , Pais , Linhagem , Bases de Dados Genéticas , Humanos , Funções Verossimilhança , Cadeias de Markov
12.
Am J Hum Genet ; 107(2): 251-264, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640185

RESUMO

Applying exome sequencing to populations with unique genetic architecture has the potential to reveal novel genes and variants associated with traits and diseases. We sequenced and analyzed the exomes of 6,716 individuals from a Southwestern American Indian (SWAI) population with well-characterized metabolic traits. We found that the SWAI population has distinct allelic architecture compared to populations of European and East Asian ancestry, and there were many predicted loss-of-function (pLOF) and nonsynonymous variants that were highly enriched or private in the SWAI population. We used pLOF and nonsynonymous variants in the SWAI population to evaluate gene-burden associations of candidate genes from European genome-wide association studies (GWASs) for type 2 diabetes, body mass index, and four major plasma lipids. We found 19 significant gene-burden associations for 11 genes, providing additional evidence for prioritizing candidate effector genes of GWAS signals. Interestingly, these associations were mainly driven by pLOF and nonsynonymous variants that are unique or highly enriched in the SWAI population. Particularly, we found four pLOF or nonsynonymous variants in APOB, APOE, PCSK9, and TM6SF2 that are private or enriched in the SWAI population and associated with low-density lipoprotein (LDL) cholesterol levels. Their large estimated effects on LDL cholesterol levels suggest strong impacts on protein function and potential clinical implications of these variants in cardiovascular health. In summary, our study illustrates the utility and potential of exome sequencing in genetically unique populations, such as the SWAI population, to prioritize candidate effector genes within GWAS loci and to find additional variants in known disease genes with potential clinical impact.


Assuntos
Exoma/genética , Predisposição Genética para Doença/genética , Índios Norte-Americanos/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Índice de Massa Corporal , Feminino , Genética Populacional/métodos , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Fenótipo , Sudoeste dos Estados Unidos
13.
Parasitol Res ; 119(9): 2829-2835, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705375

RESUMO

Cephenemyia stimulator and Oestrus ovis are two important parasitic bot flies (Oestridae) species causing myiasis, with a potential negative impact on the welfare of the host. Using next-generation sequencing approach and bioinformatics tools, a large panel of possible microsatellites loci was obtained in both species. Primer pairs were designed for 15 selected microsatellite loci in C. stimulator and other 15 loci in O. ovis for PCR amplification. Loci amplification and analysis were performed in four populations of each species. The results demonstrated that all selected loci were polymorphic, with the number of alleles ranging from 2 to 6 per locus in C. stimulator and 3 to 13 per locus in O. ovis. This is the first time to describe these microsatellite loci for C. stimulator and O. ovis. These two sets of microsatellite markers could be further used for biogeographic and population genetics studies.


Assuntos
Dípteros/genética , Repetições de Microssatélites/genética , Alelos , Animais , Dípteros/classificação , Genética Populacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Miíase/parasitologia , Reação em Cadeia da Polimerase , Ovinos
14.
Leg Med (Tokyo) ; 47: 101741, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32682294

RESUMO

In present study, we evaluated the genetic diversities of 30 insertion/deletion (InDel) loci and analyzed the genetic relationships between Daur and other comparison populations. In the studied Daur group, any two InDel loci showed no linkage disequilibrium, and all loci showed no deviations from exact tests of Hardy-Weinberg equilibrium. Insertion allele frequencies at 30 InDel loci ranged from 0.1459 (HLD39) to 0.8774 (HLD118). The observed heterozygosity and expected heterozygosity values were ranged from 0.1984 (HLD118) to 0.5564 (HLD6) and 0.2155 (HLD118) to 0.5000 (HLD92 and HLD6), respectively. The combined power of discrimination and power of exclusion values were 0.999999999993428 and 0.9878, respectively, which indicated that this panel of 30 InDels could be used for individual identifications in Daur group. Population genetic analyses including pairwise fixation index, STRUCTURE analysis, principal component analysis, genetic distance, multidimensional scaling analysis and phylogenetic analysis demonstrated that the Daur group had the closer genetic relationships with the groups from western China in comparison with other continental populations.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Grupos Étnicos/genética , Genética Forense/métodos , Frequência do Gene/genética , Loci Gênicos/genética , Variação Genética/genética , Genética Populacional/métodos , Mutação INDEL/genética , China/etnologia , Feminino , Heterozigoto , Humanos , Masculino
15.
Sci Rep ; 10(1): 9409, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523081

RESUMO

Understanding the population genetic consequences of habitat heterogeneity requires assessing whether patterns of gene flow correspond to landscape configuration. Studies of the genetic structure of populations are still scarce for Neotropical forest birds. We assessed range-wide genetic structure and contemporary gene flow in the thorn-tailed rayadito (Aphrastura spinicauda), a passerine bird inhabiting the temperate forests of South America. We used 12 microsatellite loci to genotype 582 individuals from eight localities across a large latitudinal range (30°S-56°S). Using population structure metrics, multivariate analyses, clustering algorithms, and Bayesian methods, we found evidence for moderately low regional genetic structure and reduced gene flow towards the range margins. Genetic differentiation increased with geographic distance, particularly in the southern part of the species' distribution where forests are continuously distributed. Populations in the north seem to experience limited gene flow likely due to forest discontinuity, and may comprise a demographically independent unit. The southernmost population, on the other hand, is genetically depauperate and different from all other populations. Different analytical approaches support the presence of three to five genetic clusters. We hypothesize that the genetic structure of the species follows a hierarchical clustered pattern.


Assuntos
Fluxo Gênico/genética , Passeriformes/genética , Animais , Teorema de Bayes , Análise por Conglomerados , Ecossistema , Florestas , Variação Genética/genética , Genética Populacional/métodos , Genótipo , Repetições de Microssatélites/genética , Análise de Sequência de DNA/métodos , América do Sul
16.
Leg Med (Tokyo) ; 46: 101726, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32526672

RESUMO

China harbors 56 ethnic groups and Han is the largest population. It is informative and useful to explore the available population genetic characteristics of Chinese Han population from Fujian Province, Southeast China. In our study, we explored the genetic characteristics of 20 autosomal Short tandem repeat (STR) loci in 1555 unrelated Chinese Han individuals from Zhangzhou City, Southeastern China using the SureID® 21G Human STR Identification Kit. Moreover, phylogenetic analysis was performed between the Zhangzhou Han population and other relevant populations based on the shared autosomal STR genotyping. The neighbor-joining tree and multidimensional scaling analysis were analyzed based on the Nei's standard genetic distance. We found 262 alleles among 1555 unrelated individuals and the corresponding allele frequencies ranged from 0.5521 to 0.0003. The combined power of discrimination and exclusion of the 20 autosomal STR loci were 0.99999999999999999999999943 and 0.999999996166537, respectively. Population comparison revealed that the Zhangzhou Han population were lining up together with the southern Han populations in China while showed significant differences from other China populations. Our results found that the 20 autosomal STR loci in Zhangzhou Han population are meaningful for forensic medicine and human genetic. The genetics characteristic of Zhangzhou Han population is similar with the southern Han population in China.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Medicina Legal , Loci Gênicos/genética , Genética Populacional/métodos , Repetições de Microssatélites/genética , China , Humanos , Polimorfismo Genético
17.
Nat Commun ; 11(1): 2700, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483115

RESUMO

Northern China harbored the world's earliest complex societies based on millet farming, in two major centers in the Yellow (YR) and West Liao (WLR) River basins. Until now, their genetic histories have remained largely unknown. Here we present 55 ancient genomes dating to 7500-1700 BP from the YR, WLR, and Amur River (AR) regions. Contrary to the genetic stability in the AR, the YR and WLR genetic profiles substantially changed over time. The YR populations show a monotonic increase over time in their genetic affinity with present-day southern Chinese and Southeast Asians. In the WLR, intensification of farming in the Late Neolithic is correlated with increased YR affinity while the inclusion of a pastoral economy in the Bronze Age was correlated with increased AR affinity. Our results suggest a link between changes in subsistence strategy and human migration, and fuel the debate about archaeolinguistic signatures of past human migration.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Grão Comestível/crescimento & desenvolvimento , Genoma Humano , Migração Humana , Arqueologia/métodos , Grupo com Ancestrais do Continente Asiático/genética , Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , China , DNA Antigo/análise , Genética Populacional/métodos , Geografia , Humanos , Dinâmica Populacional , Rios , Análise de Sequência de DNA/métodos , Fatores de Tempo
18.
Am J Hum Genet ; 107(1): 60-71, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32533944

RESUMO

Adult height is one of the earliest putative examples of polygenic adaptation in humans. However, this conclusion was recently challenged because residual uncorrected stratification from large-scale consortium studies was considered responsible for the previously noted genetic difference. It thus remains an open question whether height loci exhibit signals of polygenic adaptation in any human population. We re-examined this question, focusing on one of the shortest European populations, the Sardinians, in addition to mainland European populations. We utilized height-associated loci from the Biobank Japan (BBJ) dataset to further alleviate concerns of biased ascertainment of GWAS loci and showed that the Sardinians remain significantly shorter than expected under neutrality (∼0.22 standard deviation shorter than Utah residents with ancestry from northern and western Europe [CEU] on the basis of polygenic height scores, p = 3.89 × 10-4). We also found the trajectory of polygenic height scores between the Sardinian and the British populations diverged over at least the last 10,000 years (p = 0.0082), consistent with a signature of polygenic adaptation driven primarily by the Sardinian population. Although the polygenic score-based analysis showed a much subtler signature in mainland European populations, we found a clear and robust adaptive signature in the UK population by using a haplotype-based statistic, the trait singleton density score (tSDS), driven by the height-increasing alleles (p = 9.1 × 10-4). In summary, by ascertaining height loci in a distant East Asian population, we further supported the evidence of polygenic adaptation at height-associated loci among the Sardinians. In mainland Europeans, the adaptive signature was detected in haplotype-based analysis but not in polygenic score-based analysis.


Assuntos
Adaptação Fisiológica/genética , Estatura/genética , Herança Multifatorial/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Bancos de Espécimes Biológicos , Grupo com Ancestrais do Continente Europeu/genética , Genética Populacional/métodos , Genoma Humano/genética , Estudo de Associação Genômica Ampla/métodos , Haplótipos/genética , Humanos , Itália , Japão , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética/genética
19.
Am J Hum Genet ; 107(1): 137-148, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32533945

RESUMO

Recombination rates vary significantly across the genome, and estimates of recombination rates are needed for downstream analyses such as haplotype phasing and genotype imputation. Existing methods for recombination rate estimation are limited by insufficient amounts of informative genetic data or by high computational cost. We present a method and software, called IBDrecomb, for using segments of identity by descent to infer recombination rates. IBDrecomb can be applied to sequenced population cohorts to obtain high-resolution, population-specific recombination maps. In simulated admixed data, IBDrecomb obtains higher accuracy than admixture-based estimation of recombination rates. When applied to 2,500 simulated individuals, IBDrecomb obtains similar accuracy to a linkage-disequilibrium (LD)-based method applied to 96 individuals (the largest number for which computation is tractable). Compared to LD-based maps, our IBD-based maps have the advantage of estimating recombination rates in the recent past rather than the distant past. We used IBDrecomb to generate new recombination maps for European Americans and for African Americans from TOPMed sequence data from the Framingham Heart Study (1,626 unrelated individuals) and the Jackson Heart Study (2,046 unrelated individuals), and we compare them to LD-based, admixture-based, and family-based maps.


Assuntos
Recombinação Genética/genética , Afro-Americanos/genética , Grupo com Ancestrais do Continente Europeu/genética , Genética Populacional/métodos , Genoma Humano/genética , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Polimorfismo de Nucleotídeo Único/genética
20.
PLoS Genet ; 16(6): e1008867, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555579

RESUMO

Recent research shows that introgression between closely-related species is an important source of adaptive alleles for a wide range of taxa. Typically, detection of adaptive introgression from genomic data relies on comparative analyses that require sequence data from both the recipient and the donor species. However, in many cases, the donor is unknown or the data is not currently available. Here, we introduce a genome-scan method-VolcanoFinder-to detect recent events of adaptive introgression using polymorphism data from the recipient species only. VolcanoFinder detects adaptive introgression sweeps from the pattern of excess intermediate-frequency polymorphism they produce in the flanking region of the genome, a pattern which appears as a volcano-shape in pairwise genetic diversity. Using coalescent theory, we derive analytical predictions for these patterns. Based on these results, we develop a composite-likelihood test to detect signatures of adaptive introgression relative to the genomic background. Simulation results show that VolcanoFinder has high statistical power to detect these signatures, even for older sweeps and for soft sweeps initiated by multiple migrant haplotypes. Finally, we implement VolcanoFinder to detect archaic introgression in European and sub-Saharan African human populations, and uncovered interesting candidates in both populations, such as TSHR in Europeans and TCHH-RPTN in Africans. We discuss their biological implications and provide guidelines for identifying and circumventing artifactual signals during empirical applications of VolcanoFinder.


Assuntos
Introgressão Genética , Genética Populacional/métodos , Genoma Humano/genética , Modelos Genéticos , Polimorfismo Genético , África ao Sul do Saara , Grupo com Ancestrais do Continente Africano/genética , Alelos , Antígenos/genética , Simulação por Computador , Europa (Continente) , Grupo com Ancestrais do Continente Europeu/genética , Evolução Molecular , Haplótipos , Humanos , Proteínas de Filamentos Intermediários/genética , Receptores da Tireotropina/genética , Proteínas S100/genética , Seleção Genética , Software
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