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1.
Hum Genet ; 136(4): 387-397, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28197769

RESUMEN

Crohn's disease (CD) involves chronic inflammation in the gastrointestinal tract due to dysregulation of the host immune response to the gut microbiome. Even though the host-microbiome interactions are likely contributors to the development of CD, a few studies have detected genetic variants that change bacterial compositions and increase CD risk. We focus on one of the well-replicated susceptible genes, tumor necrosis factor superfamily member 15 (TNFSF15), and apply statistical analyses for personal profiles of genotypes and salivary microbiota collected from CD cases and controls in the Ryukyu Islands, southernmost islands of the Japanese archipelago. Our association test confirmed the susceptibility of TNFSF15 in the Ryukyu Islands. We found that the recessive model was supported to fit the observed genotype frequency of risk alleles slightly better than the additive model, defining the genetic effect on CD if a pair of the chromosomes in an individual consists of all risk alleles. The combined analysis of haplotypes and salivary microbiome from a small set of samples showed a significant association of the genetic effect with the increase of Prevotella, which led to a significant increase of CD risk. However, the genetic effect on CD disappeared if the abundance of Prevotella was low, suggesting the genetic contribution to CD is conditionally independent given a fixed amount of Prevotella. Although our statistical power is limited due to the small sample size, these results support an idea that the genetic susceptibility of TNFSF15 to CD may be confounded, in part, by the increase of Prevotella.


Asunto(s)
Enfermedad de Crohn/genética , Predisposición Genética a la Enfermedad , Microbiota , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Estudios de Casos y Controles , Factores de Confusión Epidemiológicos , Humanos , Japón , Modelos Logísticos , Polimorfismo de Nucleótido Simple , Saliva/microbiología
2.
Am J Hum Biol ; 29(2)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27801545

RESUMEN

OBJECTIVES: A cline of frequencies of the derived allele of the ALDH2 gene, which causes a deficiency of an enzyme and "facial flushing" in humans who drink alcohol, has been known among the people of the Japanese archipelago. This cline is conventionally explained by admixture with immigrants from the Asian continent occurring during the Yayoi period. Previous studies lack sufficient data from the peripheral regions of the indigenous Jomon people, and those data the ADH1B gene that is involved in the Class I ADH gene cluster and contains another variant leading to a functional change. METHODS: We focused on the southwestern-most people from the Ryukyu Islands (n = 218) and those from northern Kyushu (n = 21) where the Yayoi immigrants likely arrived. We investigated both the Class I ADH and ALDH2 loci, as well as neutral genetic markers. RESULTS: In the Ryukyu Islands, the frequencies of the ancestral alleles in both loci were always higher than those in mainland Japan, while the frequencies of ADH1B were less than those of the derived allele. A haplotype block was not observed in ALDH2 but was in Class I ADH. DISCUSSION: Our data suggest that the derived allele of ALDH2 came with the Yayoi immigrants from the Asian continent to the Japanese archipelago. However, the derived allele of ADH1B is unlikely to be related to the Yayoi migration. Therefore, we postulate that the expansion of the derived allele of ADHIB in East Asia could be traced back to the last glacial period.


Asunto(s)
Alcohol Deshidrogenasa/genética , Aldehído Deshidrogenasa Mitocondrial/genética , Frecuencia de los Genes , Polimorfismo Genético , Asia Oriental , Femenino , Humanos , Islas , Japón , Masculino
3.
Mol Biol Evol ; 32(6): 1533-43, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25758010

RESUMEN

Various hypotheses for the peopling of the Japanese archipelago have been proposed, which can be classified into three models: transformation, replacement, and hybridization. In recent years, one of the hybridization models ("dual-structure model") has been widely accepted. According to this model, Neolithic hunter-gatherers known as Jomon, who are assumed to have originated in southeast Asia and lived in the Japanese archipelago greater than 10,000 years ago, admixed with an agricultural people known as Yayoi, whom were migrants from the East Asian continent 2,000-3,000 years ago. Meanwhile, some anthropologists propose that rather, morphological differences between the Jomon and Yayoi people can be explained by microevolution following the lifestyle change. To resolve this controversy, we compared three demographic models by approximate Bayesian computation using genome-wide single nucleotide polymorphism (gwSNP) data from the Ainu people who are thought to be direct descendants of indigenous Jomon. If we assume Chinese people sampled in Beijing from HapMap have the same ancestry as Yayoi, then the hybridization model is predicted to be between 29 and 63 times more likely than the replacement and transformation models, respectively. Furthermore, our data provide strong support for a model in which the Jomon lineages had population structure diversified in local areas before the admixture event. Initial divergence between the Jomon and Yayoi ancestries was dated to late Pleistocene, followed by the divergence of Jomon lineages at early Holocene. These results suggest gwSNP data provides a detailed picture of the complex hybridization model for Japanese population history.


Asunto(s)
Pueblo Asiatico/genética , Genética de Población , Polimorfismo de Nucleótido Simple , Teorema de Bayes , Demografía , Estudios de Asociación Genética , Humanos , Hibridación Genética , Japón , Modelos Genéticos
4.
Mol Biol Evol ; 31(11): 2929-40, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25086001

RESUMEN

The Ryukyu Islands are located to the southwest of the Japanese archipelago. Archaeological evidence has revealed the existence of prehistoric cultural differentiation between the northern Ryukyu islands of Amami and Okinawa, and the southern Ryukyu islands of Miyako and Yaeyama. To examine a genetic subdivision in the Ryukyu Islands, we conducted genome-wide single nucleotide polymorphism typing of inhabitants from the Okinawa Islands, the Miyako Islands, and the Yaeyama Islands. Principal component and cluster analyses revealed genetic differentiation among the island groups, especially between Okinawa and Miyako. No genetic affinity was observed between aboriginal Taiwanese and any of the Ryukyu populations. The genetic differentiation observed between the inhabitants of the Okinawa Islands and the Miyako Islands is likely to have arisen due to genetic drift rather than admixture with people from neighboring regions. Based on the observed genetic differences, the divergence time between the inhabitants of Okinawa and Miyako islands was dated to the Holocene. These findings suggest that the Pleistocene inhabitants, whose bones have been found on the southern Ryukyu Islands, did not make a major genetic contribution, if any, to the present-day inhabitants of the southern Ryukyu Islands.


Asunto(s)
Pueblo Asiatico , Flujo Genético , Genoma Humano , Polimorfismo de Nucleótido Simple , Análisis por Conglomerados , Femenino , Genética de Población , Humanos , Islas , Japón , Masculino , Paleontología , Análisis de Componente Principal , Aislamiento Reproductivo
5.
J Hum Evol ; 87: 95-106, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26164107

RESUMEN

The modern human expansion process out of Africa has important implications for understanding the genetic and phenotypic structure of extant populations. While intensely debated, the primary hypotheses focus on either a single dispersal or multiple dispersals out of the continent. Here, we use the human fossil record from Africa and the Levant, as well as an exceptionally large dataset of Holocene human crania sampled from Asia, to model ancestor-descendant relationships along hypothetical dispersal routes. We test the spatial and temporal predictions of competing out-of-Africa models by assessing the correlation of geographical distances between populations and measures of population differentiation derived from quantitative cranial phenotype data. Our results support a model in which extant Australo-Melanesians are descendants of an initial dispersal out of Africa by early anatomically modern humans, while all other populations are descendants of a later migration wave. Our results have implications for understanding the complexity of modern human origins and diversity.


Asunto(s)
Evolución Biológica , Fósiles/anatomía & histología , Dinámica Poblacional , Cráneo/anatomía & histología , África , Asia , Cefalometría , Geografía , Humanos , Medio Oriente
6.
Proc Biol Sci ; 281(1797)2014 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-25377463

RESUMEN

Sexual dimorphisms, which are phenotypic differences between males and females, are driven by sexual selection. Interestingly, sexually selected traits show geographical variations within species despite strong directional selective pressures. This paradox has eluded many evolutionary biologists for some time, and several models have been proposed (e.g. 'indicator model' and 'trade-off model'). However, disentangling which of these theories explains empirical patterns remains difficult, because genetic polymorphisms that cause variation in sexual differences are still unknown. In this study, we show that polymorphisms in cytochrome P450 (CYP) 1B1, which encodes a xenobiotic-metabolizing enzyme, are associated with geographical differences in sexual dimorphism in the anal fin morphology of medaka fish (Oryzias latipes). Biochemical assays and genetic cross experiments show that high- and low-activity CYP1B1 alleles enhanced and declined sex differences in anal fin shapes, respectively. Behavioural and phylogenetic analyses suggest maintenance of the high-activity allele by sexual selection, whereas the low-activity allele possibly has experienced positive selection due to by-product effects of CYP1B1 in inferred ancestral populations. The present data can elucidate evolutionary mechanisms behind genetic variations in sexual dimorphism and indicate trade-off interactions between two distinct mechanisms acting on the two alleles with pleiotropic effects of xenobiotic-metabolizing enzymes.


Asunto(s)
Alelos , Proteínas de Peces/genética , Oryzias/genética , Caracteres Sexuales , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Geografía , Masculino , Datos de Secuencia Molecular , Oryzias/anatomía & histología , Oryzias/metabolismo , Polimorfismo Genético , Conducta Sexual Animal
7.
Am J Phys Anthropol ; 154(3): 334-48, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24643445

RESUMEN

Different data types have previously been shown to have the same microevolutionary patterns in worldwide data sets. However, peopling of the New World studies have shown a difference in migration paths and timings using multiple types of data, spurring research to understand why this is the case. This study was designed to test the degree of similarity in evolutionary patterns by using cranial and dental metric and nonmetric data, along with Y-chromosome DNA and mtDNA. The populations used included Inuits from Alaska, Canada, Siberia, Greenland, and the Aleutian Islands. For comparability, the populations used for the cranial and molecular data were from similar geographic regions or had a shared population history. Distance, R and kinship matrices were generated for use in running Mantel tests, PROTEST analyses, and Procrustes analyses. A clear patterning was seen, with the craniometric data being most highly correlated to the mtDNA data and the cranial nonmetric data being most highly correlated with the Y-chromosome data, while the phenotypic data were also linked. This patterning is suggestive of a possible male or female inheritance, or the correlated data types are affected by the same or similar evolutionary forces. The results of this study indicate cranial traits have some degree of heritability. Moreover, combining data types leads to a richer knowledge of biological affinity. This understanding is important for bioarchaeological contexts, in particular, peopling of the New World studies where focusing on reconciling the results from comparing multiple data types is necessary to move forward.


Asunto(s)
Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Inuk/estadística & datos numéricos , Modelos Estadísticos , Cráneo/anatomía & histología , Diente/anatomía & histología , Alaska , Antropología Física/métodos , Canadá , Cefalometría , Evolución Molecular , Femenino , Variación Genética , Genética de Población , Historia Antigua , Migración Humana/historia , Migración Humana/estadística & datos numéricos , Humanos , Masculino , Odontometría , Siberia
8.
Glycobiology ; 23(1): 91-105, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22948803

RESUMEN

Whereas the Galß1-4Gal epitope is rarely found in mammalian glycans, it has been found in glycans of various species of non-mammalian vertebrates, such as fish, amphibians and birds. Although glycans containing Galß1-4Gal in these vertebrates were detected by precise structural analysis of the glycans using mass spectrometry and/or NMR spectrometry, there are no convenient methods to detect Galß1-4Gal from various samples. To analyze systematically the distribution of Galß1-4Gal in nature, we generated mouse monoclonal antibodies (mAbs) specific for Galß1-4Gal using extracts of medaka eggs as an immunogen. Four mAbs (two immunoglobulin (Ig)Ms and two IgG1s) were obtained by enzyme-linked immunosorbent assay-based screening. The specificities of these mAbs were evaluated by frontal affinity chromatography using 142 kinds of 2-aminopyridine (PA)-derivatized oligosaccharides. While all mAbs interacted with (Galß1-4Gal)-containing oligosaccharides at their non-reducing termini with dissociation constants (K(d)) ranging from 1.0 x 10⁻5 to 2.8 x 10⁻4 M, no apparent interaction was observed with any other glycans. The number of branches containing Galß1-4Gal on N-glycans did not significantly affect K(d) of mAbs of IgG1 subclasses, but those of IgM mAbs were decreased by ∼1 order of magnitude, in increments of the number of branches present. Using the mAbs, we established that Galß1-4Gal is also expressed on glycoproteins in various tissues from the African clawed frog. Immunohistochemical staining of medaka sections revealed that Galß1-4Gal epitopes were expressed in the endothelium, epithelium and epidermis, which directly contact the external environment or invading organisms. Thus, these mAbs are useful for systematically investigating the species-specific expression of glycans, which may act as a barrier against infection.


Asunto(s)
Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Epítopos/inmunología , Polisacáridos/química , Animales , Anticuerpos Monoclonales/metabolismo , Aves , Disacáridos/química , Disacáridos/inmunología , Epítopos/química , Glicoproteínas/química , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Ratones , Ratones Endogámicos BALB C , Oligosacáridos/química , Oligosacáridos/inmunología , Especificidad de Órganos , Oryzias , Polisacáridos/inmunología , Polisacáridos/metabolismo , Especificidad de la Especie , Xenopus laevis , Pez Cebra
9.
Nature ; 448(7151): 346-8, 2007 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-17637668

RESUMEN

The origin and patterns of dispersal of anatomically modern humans are the focus of considerable debate. Global genetic analyses have argued for one single origin, placed somewhere in Africa. This scenario implies a rapid expansion, with a series of bottlenecks of small amplitude, which would have led to the observed smooth loss of genetic diversity with increasing distance from Africa. Analyses of cranial data, on the other hand, have given mixed results, and have been argued to support multiple origins of modern humans. Using a large data set of skull measurements and an analytical framework equivalent to that used for genetic data, we show that the loss in genetic diversity has been mirrored by a loss in phenotypic variability. We find evidence for an African origin, placed somewhere in the central/southern part of the continent, which harbours the highest intra-population diversity in phenotypic measurements. We failed to find evidence for a second origin, and we confirm these results on a large genetic data set. Distance from Africa accounts for an average 19-25% of heritable variation in craniometric measurements-a remarkably strong effect for phenotypic measurements known to be under selection.


Asunto(s)
Evolución Biológica , Variación Genética , Geografía , Densidad de Población , Cráneo/anatomía & histología , África , Clima , Emigración e Inmigración , Femenino , Historia Antigua , Humanos , Masculino , Fenotipo , Filogenia
10.
PNAS Nexus ; 2(7): pgad217, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37457893

RESUMEN

There is a growing consensus that global patterns of modern human cranial and dental variation are shaped largely by neutral evolutionary processes, suggesting that craniodental features can be used as reliable proxies for inferring population structure and history in bioarchaeological, forensic, and paleoanthropological contexts. However, there is disagreement on whether certain types of data preserve a neutral signature to a greater degree than others. Here, we address this unresolved question and systematically test the relative neutrality of four standard metric and nonmetric craniodental data types employing an extensive computational genotype-phenotype comparison across modern populations from around the world. Our computation draws on the largest existing data sets currently available, while accounting for geographically structured environmental variation, population sampling uncertainty, disparate numbers of phenotypic variables, and stochastic variation inherent to a neutral model of evolution. Our results reveal that the four data types differentially capture neutral genomic variation, with highest signals preserved in dental nonmetric and cranial metric data, followed by cranial nonmetric and dental metric data. Importantly, we demonstrate that combining all four data types together maximizes the neutral genetic signal compared with using them separately, even with a limited number of phenotypic variables. We hypothesize that this reflects a lower level of genetic integration through pleiotropy between, compared to within, the four data types, effectively forming four different modules associated with relatively independent sets of loci. Therefore, we recommend that future craniodental investigations adopt holistic combined data approaches, allowing for more robust inferences about underlying neutral genetic variation.

11.
PLoS One ; 18(5): e0285264, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37141293

RESUMEN

Dental size variation in modern humans has been assessed from regional to worldwide scales, especially under microevolutionary and forensic contexts. Despite this, populations of mixed continental ancestry such as contemporary Latin Americans remain unexplored. In the present study we investigated a large Latin American sample from Colombia (N = 804) and obtained buccolingual and mesiodistal diameters and three indices for maxillary and mandibular teeth (except third molars). We evaluated the correlation between 28 dental measurements (and three indices) with age, sex and genomic ancestry (estimated using genome-wide SNP data). In addition, we explored correlation patterns between dental measurements and the biological affinities, based on these measurements, between two Latin American samples (Colombians and Mexicans) and three putative parental populations: Central and South Native Americans, western Europeans and western Africans through PCA and DFA. Our results indicate that Latin Americans have high dental size diversity, overlapping the variation exhibited by the parental populations. Several dental dimensions and indices have significant correlations with sex and age. Western Europeans presented closer biological affinities with Colombians, and the European genomic ancestry exhibited the highest correlations with tooth size. Correlations between tooth measurements reveal distinct dental modules, as well as a higher integration of postcanine dentition. The effects on dental size of age, sex and genomic ancestry is of relevance for forensic, biohistorical and microevolutionary studies in Latin Americans.


Asunto(s)
Grupos Raciales , Diente , Humanos , Genómica , Hispánicos o Latinos , Grupos Raciales/genética , Diente/anatomía & histología
12.
Am J Hum Genet ; 85(4): 528-35, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19804850

RESUMEN

Shovel shape of upper incisors is a common characteristic in Asian and Native American populations but is rare or absent in African and European populations. Like other common dental traits, genetic polymorphisms involved in the tooth shoveling have not yet been clarified. In ectodysplasin A receptor (EDAR), where dysfunctional mutations cause hypohidrotic ectodermal dysplasia, there is a nonsynonymous-derived variant, 1540C (rs3827760), that has a geographic distribution similar to that of the tooth shoveling. This allele has been recently reported to be associated with Asian-specific hair thickness. We aimed to clarify whether EDAR 1540C is also associated with dental morphology. For this purpose, we measured crown diameters and tooth-shoveling grades and analyzed the correlations between the dental traits and EDAR genotypes in two Japanese populations, inhabitants around Tokyo and in Sakishima Islands. The number of EDAR 1540C alleles in an individual was strongly correlated with the tooth-shoveling grade (p = 7.7 x 10(-10)). The effect of the allele was additive and explained 18.9% of the total variance in the shoveling grade, which corresponds to about one-fourth of the heritability of the trait reported previously. For data reduction of individual-level metric data, we applied a principal-component analysis, which yielded PC1-4, corresponding to four patterns of tooth size; this result implies that multiple factors are involved in dental morphology. The 1540C allele also significantly affected PC1 (p = 4.9 x 10(-3)), which denotes overall tooth size, and PC2 (p = 2.6 x 10(-3)), which denotes the ratio of mesiodistal diameter to buccolingual diameter.


Asunto(s)
Receptor Edar/genética , Variación Genética , Diente/anatomía & histología , Alelos , Femenino , Genoma , Genotipo , Humanos , Japón , Masculino , Modelos Genéticos , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Análisis de Componente Principal , Análisis de Regresión , Diente/fisiología
13.
J Hum Genet ; 57(8): 508-14, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22648185

RESUMEN

Dental morphology is highly diverse among individuals and between human populations. Although it is thought that genetic factors mainly determine common dental variations, only a few such genetic factors have been identified. One study demonstrated that a nonsynonymous single-nucleotide polymorphism (370V/A, rs3827760) in the ectodysplasin A receptor gene (EDAR) is associated with shoveling and double-shoveling grades of upper first incisors and tooth crown size. Here, we examined the association of EDAR 370V/A with several dental characters in Korean and Japanese subjects. A meta-analysis that combined analyses of Korean and Japanese subjects revealed that the Asian-specific 370A allele is associated with an increase in the grades of shoveling and double shoveling, as previously found. We also showed a highly significant association between EDAR 370V/A genotype and crown size, especially mesiodistal diameters of anterior teeth. Moreover, we found that the 370A allele was associated with the presence of hypoconulids of lower second molars. These results indicated that the EDAR polymorphism is responsible, in part, for the Sinodonty and Sundadonty dichotomy in Asian populations, and clearly demonstrated that the EDAR polymorphism has pleiotropic effects on tooth morphology. As the 370A allele is known to be a most likely target of positive selection in Asian populations, some phenotypes associated with the variant may be 'hitchhiking phenotypes', while others may be actual targets of selection.


Asunto(s)
Pueblo Asiatico/genética , Receptor Edar/genética , Estudios de Asociación Genética , Diente/anatomía & histología , Alelos , Genotipo , Humanos , Incisivo/anatomía & histología , Diente Molar/anatomía & histología , Fenotipo , Polimorfismo de Nucleótido Simple , Corona del Diente/anatomía & histología
14.
Sci Rep ; 12(1): 13826, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35970916

RESUMEN

This study assessed the regional diversity of the human cranial form by using geometric homologous models based on scanned data from 148 ethnic groups worldwide. This method adopted a template-fitting technique for a nonrigid transformation via the iterative closest point algorithm to generate the homologous meshes. Through the application of principal component analysis to 342 sampled homologous models, the largest variation was detected in overall size, and small South Asian crania were clearly verified. The next greatest diversity was found in the length/breadth proportion of the neurocranium, which showed the contrast between the elongated crania of Africans and the globular crania of Northeast Asians. Notably, this component was slightly correlated with the facial profile. Well-known facial features, such as the forward projection of the cheek among Northeast Asians and compaction of the European maxilla, were reconfirmed. These facial variations were highly correlated with the calvarial outline, particularly the degree of frontal and occipital inclines. An allometric pattern was detected in facial proportions in relation to overall cranial size; in larger crania, the facial profiles tend to be longer and narrower, as demonstrated among many American natives and Northeast Asians. Although our study did not include data on environmental variables that are likely to affect cranial morphology, such as climate or dietary conditions, the large datasets of homologous cranial models will be usefully available for seeking various attributions to phenotypic skeletal characteristics.


Asunto(s)
Cara , Cráneo , Pesos y Medidas Corporales , Clima , Cara/anatomía & histología , Humanos , Análisis de Componente Principal , Cráneo/anatomía & histología
15.
Sci Rep ; 11(1): 20830, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34675295

RESUMEN

This study reports a cranio-morphometric analysis of female human remains from seven archaeological sites in China, Vietnam and Taiwan that date between 16,000 and 5300 BP. The aim of the analysis is to test the "two-layer" model of human dispersal in eastern Eurasia, using previously unanalysed female remains to balance the large sample of previously-analysed males. The resulting craniometric data indicate that the examined specimens all belong to the "first layer" of dispersal, and share a common ancestor with recent Australian and Papuan populations, and the ancient Jomon people of Japan. The analysed specimens pre-date the expansion of agricultural populations of East/Northeast Asian origin-that is, the "second layer" of human dispersal proposed by the model. As a result of this study, the two-layer model, which has hitherto rested on evidence only from male skeletons, is now strongly supported by female-derived data. Further comparisons reveal that the people of the first layer were closer in terms of their facial morphology to modern Africans and Sri Lankan Veddah than to modern Asians and Europeans, suggesting that the Late Pleistocene through Middle Holocene hunter-gatherers examined in this study were direct descendants of the anatomically modern humans who first migrated out of Africa through southern Eurasia.


Asunto(s)
Cefalometría , Migración Humana , Cráneo/anatomía & histología , Arqueología , China , Femenino , Humanos , Masculino , Taiwán , Vietnam
16.
Genome Biol Evol ; 13(9)2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34410389

RESUMEN

Recent studies on paleogenomics have reported some Paleolithic and Neolithic genomes that have provided new insights into the human population history in East and Northeast Asia. However, there remain some cases where more recent migration events need to be examined to elucidate the detailed formation process of local populations. Although the area around northern Japan is one of the regions archaeologically suggested to have been affected by migration waves after the Neolithic period, the genetic source of these migrations are still unclear. Thus, genomic data from such past migrant populations would be highly informative to clarify the detailed formation process of local populations in this region. Here, we report the genome sequence of a 900-year-old adult female (NAT002) belonging to the prehistoric Okhotsk people, who have been considered to be the past migrants to northern Japan after the Neolithic period. We found a close relationship between NAT002 and modern Lower Amur populations and past admixture events between the Amur, Jomon, and Kamchatka ancestries. The admixture dating suggested migration of Amur-related ancestry at approximately 1,600 BP, which is compatible with the archaeological evidence regarding the settlement of the Okhotsk people. Our results also imply migration of Kamchatka-related ancestry at approximately 2,000 BP. In addition, human leukocyte antigen (HLA) typing detected the HLA-B*40 allele, which is reported to increase the risk of arthritis, suggesting the genetic vulnerability of NAT002 to hyperostosis, which was observed around her chest clavicle.


Asunto(s)
Genoma Humano , Genómica , Asia Oriental , Femenino , Migración Humana , Humanos , Japón , Paleontología , Esqueleto
17.
Am J Phys Anthropol ; 141(1): 76-82, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19582777

RESUMEN

Human populations across the world vary greatly in cranial morphology. It is highly debated to what extent this variability has accumulated through neutral processes (genetic drift) or through natural selection driven by climate. By taking advantage of recent work showing that geographic distance along landmasses is an excellent proxy for neutral genetic differentiation, we quantify the relative role of drift versus selection in an exceptionally large dataset of human skulls. We show that neutral processes have been much more important than climate in shaping the human cranium. We further demonstrate that a large proportion of the signal for natural selection comes from populations from extremely cold regions. More generally, we show that, if drift is not explicitly accounted for, the effect of natural selection can be greatly overestimated.


Asunto(s)
Flujo Genético , Cráneo/anatomía & histología , Evolución Biológica , Tamaño Corporal , Clima , Femenino , Fósiles , Geografía , Humanos , Modelos Lineales , Masculino , Fenotipo , Selección Genética
18.
Am J Hum Biol ; 22(2): 163-71, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19593740

RESUMEN

Gene flow and genetic drift are important factors affecting geographic variations in human phenotypic traits. In the present study, the effects of gene flow from an outside source on the pattern of within- and among-group variation of the Ainu from Sakhalin Island and three local groups of Hokkaido are examined by applying an R-matrix approach to metric and nonmetric dental data. The comparative samples consist of their ancestral and neighboring populations, such as the Neolithic Jomon, the subsequent Epi-Jomon/Satsumon, the Okhotsk culture people who migrated from Northeast Asia to the northeastern part of Hokkaido during a period 1600-900 years B.P., and modern non-Ainu Japanese. The results obtained by using the census population sizes of the regional groups of the Ainu as an estimate of relative effective population size suggest the possibility of an admixture between the Okhotsk culture people and the indigenous inhabitants in Hokkaido, at least in the coastal region along the Sea of Okhotsk. Such gene flow from Northeast Asian continent may have exerted an effect on the genetic structure of the contemporary Ainu. The present findings indicate that the population structure, as represented by genetic drift and gene flow, tend to be obscured in the results obtained by standard statistical methods such as Mahalanobis' generalized distance and Smith's MMDs. The present extension of the R-matrix approach to metric and nonmetric dental data provide results that can be interpreted in terms of a genetically, archaeologically, and prehistorically suggested pattern of gene flow and isolation.


Asunto(s)
Pueblo Asiatico/genética , Flujo Génico , Flujo Genético , Diente/anatomía & histología , Emigración e Inmigración/historia , Emigración e Inmigración/estadística & datos numéricos , Femenino , Variación Genética , Historia Antigua , Humanos , Japón , Masculino , Modelos Genéticos , Modelos Estadísticos , Siberia/etnología
19.
Am J Hum Biol ; 22(6): 782-90, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20721979

RESUMEN

OBJECTIVES: The purpose of this study is to investigate the origin and expansion of the Jomon population, the Neolithic inhabitants of the Japanese archipelago, and peopling East/Northeast Asian region through a global comparison between the prehistoric samples from around the world. METHODS: R-matrix approach was applied to 20 nonmetric cranial traits for assessing the population structure and history of the Jomon. Pattern of ancient group relationships on a global scale was presented using network splitstree applied to distance matrix transformed from the R-matrix. RESULTS: The phenotypic variation is largest in Hokkaido region, followed by the regions of eastern Japan. The Chugoku region, the southwestern part of Japan, shows larger variance than eastern Japan. Global analyses including samples from Northeast Asia, Southeast Asia, Australia, West Asia, Europe, and North Africa dating roughly to the same chronological periods as those of the Jomon groups, indicate northern affinities of the Jomon and the distinction between Southeast and Northeast Asian series. CONCLUSION: The Jomon ancestors of the northern part of Japan might have expanded southward to Honshu Island with a series of bottlenecks. A possible gene flow from outside source or heterogeneous origin of western Jomon group was, at the same time, suggested. The network relationships of the Jomon with Northeast Asians and, to a lesser extent, with Southeast Asians based on the splitstree analysis may allow us to suppose that the Jomon may be one of the key populations for the studies of the evolution of eastern Asian diversity.


Asunto(s)
Pueblo Asiatico , Evolución Biológica , Cráneo/anatomía & histología , Flujo Génico , Humanos , Japón , Fenotipo , Densidad de Población
20.
Commun Biol ; 3(1): 437, 2020 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-32843717

RESUMEN

Anatomically modern humans reached East Asia more than 40,000 years ago. However, key questions still remain unanswered with regard to the route(s) and the number of wave(s) in the dispersal into East Eurasia. Ancient genomes at the edge of the region may elucidate a more detailed picture of the peopling of East Eurasia. Here, we analyze the whole-genome sequence of a 2,500-year-old individual (IK002) from the main-island of Japan that is  characterized with a typical Jomon culture. The phylogenetic analyses support multiple waves of migration, with IK002 forming a basal lineage to the East and Northeast Asian genomes examined, likely representing some of the earliest-wave migrants who went north from Southeast Asia to East Asia. Furthermore, IK002 shows strong genetic affinity with the indigenous Taiwan aborigines, which may support a coastal route of the Jomon-ancestry migration. This study highlights the power of ancient genomics to provide new insights into the complex history of human migration into East Eurasia.


Asunto(s)
Pueblo Asiatico/genética , Genoma Humano , Migración Humana , Análisis de Secuencia de ADN , Secuencia de Bases , ADN Antiguo/análisis , Asia Oriental , Humanos , Estadística como Asunto
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