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The Oirats are a group of Mongolian-speaking peoples residing in Russia, China, and Mongolia, who speak Oirat dialects of the Mongolian language. Migrations of nomadic ethnopolitical formations of the Oirats across the Eurasian Steppe during the Late Middle Ages/early Modern times resulted in a wide geographic spread of Oirat ethnic groups from present-day northwestern China in East Asia to the Lower Volga region in Eastern Europe. In this study, we generate new genome-wide and mitochondrial DNA data for present-day Oirat-speaking populations from Kalmykia in Eastern Europe, Western Mongolia, and the Xinjiang region of China, as well as Issyk-Kul Sart-Kalmaks from Central Asia, and historically related ethnic groups from Altai, Tuva, and Northern Mongolia to study the genetic structure and history of the Oirats. Despite their spatial and temporal separation, small current population census, both the Kalmyks of Eastern Europe and the Oirats of Western Mongolia in East Asia are characterized by strong genetic similarity, high effective population size, and low levels of interpopulation structure. This contrasts the fine genetic structure observed today at a smaller geographic scale in traditionally sedentary populations, and is conditioned by high mobility and marriage practices (traditional strict exogamy) in nomadic groups. Conversely, the genetic profile of the Issyk-Kul Sart-Kalmaks suggests a distinct source(s) of genetic ancestry, along with indications of isolation and genetic drift compared to other Oirats. Our results also show that there was limited gene flow between the ancestors of the Oirats and the Altaians during the late Middle Ages. Source of the yurt image: https://www.vecteezy.com/free-vector/yurt .
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Human Y chromosome haplogroup J1-M267 is a common male lineage in West Asia. One high-frequency region-encompassing the Arabian Peninsula, southern Mesopotamia, and the southern Levant-resides ~ 2000 km away from the other one found in the Caucasus. The region between them, although has a lower frequency, nevertheless demonstrates high genetic diversity. Studies associate this haplogroup with the spread of farming from the Fertile Crescent to Europe, the spread of mobile pastoralism in the desert regions of the Arabian Peninsula, the history of the Jews, and the spread of Islam. Here, we study past human male demography in West Asia with 172 high-coverage whole Y chromosome sequences and 889 genotyped samples of haplogroup J1-M267. We show that this haplogroup evolved ~ 20,000 years ago somewhere in northwestern Iran, the Caucasus, the Armenian Highland, and northern Mesopotamia. The major branch-J1a1a1-P58-evolved during the early Holocene ~ 9500 years ago somewhere in the Arabian Peninsula, the Levant, and southern Mesopotamia. Haplogroup J1-M267 expanded during the Chalcolithic, the Bronze Age, and the Iron Age. Most probably, the spread of Afro-Asiatic languages, the spread of mobile pastoralism in the arid zones, or both of these events together explain the distribution of haplogroup J1-M267 we see today in the southern regions of West Asia.
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Alelos , Cromosomas Humanos Y , Haplotipos , Teorema de Bayes , Evolución Molecular , Genética de Población , Humanos , Filogenia , Polimorfismo de Nucleótido Simple , Análisis Espacio-TemporalRESUMEN
In this study, we compare the genetic ancestry of individuals from two as yet genetically unstudied cultural traditions in Estonia in the context of available modern and ancient datasets: 15 from the Late Bronze Age stone-cist graves (1200-400 BC) (EstBA) and 6 from the Pre-Roman Iron Age tarand cemeteries (800/500 BC-50 AD) (EstIA). We also included 5 Pre-Roman to Roman Iron Age Ingrian (500 BC-450 AD) (IngIA) and 7 Middle Age Estonian (1200-1600 AD) (EstMA) individuals to build a dataset for studying the demographic history of the northern parts of the Eastern Baltic from the earliest layer of Mesolithic to modern times. Our findings are consistent with EstBA receiving gene flow from regions with strong Western hunter-gatherer (WHG) affinities and EstIA from populations related to modern Siberians. The latter inference is in accordance with Y chromosome (chrY) distributions in present day populations of the Eastern Baltic, as well as patterns of autosomal variation in the majority of the westernmost Uralic speakers [1-5]. This ancestry reached the coasts of the Baltic Sea no later than the mid-first millennium BC; i.e., in the same time window as the diversification of west Uralic (Finnic) languages [6]. Furthermore, phenotypic traits often associated with modern Northern Europeans, like light eyes, hair, and skin, as well as lactose tolerance, can be traced back to the Bronze Age in the Eastern Baltic. VIDEO ABSTRACT.
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ADN Antiguo/análisis , Flujo Génico , Migración Humana , Fenotipo , Arqueología , Estonia , Femenino , Historia Antigua , Historia Medieval , Humanos , MasculinoRESUMEN
Orexins, alternatively called hypocretins, are neuropeptides with crucial role in maintaining wakefulness. The orexin system is thought to mediate a coordinated defense response but thus far investigated from the flight, but never fight, response perspective. An HCRTR1 gene variant (rs2271933â¯Gâ¯>â¯A) leading to amino acid substitution (Ile408Val) has been associated with migraine and mood disorders. We genotyped, and assessed aggressive behaviour in both birth cohorts (nâ¯=â¯655 and 583) of the Estonian Children Personality Behaviour and Health Study (ECPBHS). Measures of aggressiveness were collected at age 25 or 33 and data on stressful life events (SLE-s) at age 15. Violations of traffic law were monitored in the samples of the Estonian Psychobiological Study of Traffic Behaviour. In both birth cohorts of the ECPBHS, the HCRTR1 the A/A homozygotes reported higher aggression in both Buss-Perry Aggression Questionnaire and the Life History of Aggression Interview. With either measure of aggressiveness, the HCRTR1 genotype effect was dependent on experience of SLE, the highest level of aggressiveness increase by environment being found in female A/A homozygotes. The HCRTR1 A/A homozygotes scored higher in the ANGER facet of the Affective Neuroscience Personality Scale, while such an effect on FEAR was found only in females. Male HCRTR1 A/A homozygotes were more likely to relapse into drunk driving of a passenger car, and in two independent samples the A-allele carriers were causing traffic accidents more often. Conclusively, self-report, interview, and traffic record data converge indicating that the HCRTR1 Ile408Val genotype is associated with aggressiveness and breach of law. This article is part of the Special Issue entitled 'Current status of the neurobiology of aggression and impulsivity'.
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Agresión/fisiología , Receptores de Orexina/genética , Receptores de Orexina/fisiología , Adolescente , Adulto , Afecto , Estudios de Cohortes , Femenino , Genotipo , Homocigoto , Humanos , Masculino , Inventario de Personalidad , Polimorfismo de Nucleótido Simple , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicologíaRESUMEN
The Indus Valley has been the backdrop for several historic and prehistoric population movements between South Asia and West Eurasia. However, the genetic structure of present-day populations from Northwest India is poorly characterized. Here we report new genome-wide genotype data for 45 modern individuals from four Northwest Indian populations, including the Ror, whose long-term occupation of the region can be traced back to the early Vedic scriptures. Our results suggest that although the genetic architecture of most Northwest Indian populations fits well on the broader North-South Indian genetic cline, culturally distinct groups such as the Ror stand out by being genetically more akin to populations living west of India; such populations include prehistorical and early historical ancient individuals from the Swat Valley near the Indus Valley. We argue that this affinity is more likely a result of genetic continuity since the Bronze Age migrations from the Steppe Belt than a result of recent admixture. The observed patterns of genetic relationships both with modern and ancient West Eurasians suggest that the Ror can be used as a proxy for a population descended from the Ancestral North Indian (ANI) population. Collectively, our results show that the Indus Valley populations are characterized by considerable genetic heterogeneity that has persisted over thousands of years.
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Etnicidad/genética , Variación Genética/genética , Asia , Emigración e Inmigración , Genética de Población/métodos , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Geografía , Humanos , IndiaRESUMEN
BACKGROUND: The genetic origins of Uralic speakers from across a vast territory in the temperate zone of North Eurasia have remained elusive. Previous studies have shown contrasting proportions of Eastern and Western Eurasian ancestry in their mitochondrial and Y chromosomal gene pools. While the maternal lineages reflect by and large the geographic background of a given Uralic-speaking population, the frequency of Y chromosomes of Eastern Eurasian origin is distinctively high among European Uralic speakers. The autosomal variation of Uralic speakers, however, has not yet been studied comprehensively. RESULTS: Here, we present a genome-wide analysis of 15 Uralic-speaking populations which cover all main groups of the linguistic family. We show that contemporary Uralic speakers are genetically very similar to their local geographical neighbours. However, when studying relationships among geographically distant populations, we find that most of the Uralic speakers and some of their neighbours share a genetic component of possibly Siberian origin. Additionally, we show that most Uralic speakers share significantly more genomic segments identity-by-descent with each other than with geographically equidistant speakers of other languages. We find that correlated genome-wide genetic and lexical distances among Uralic speakers suggest co-dispersion of genes and languages. Yet, we do not find long-range genetic ties between Estonians and Hungarians with their linguistic sisters that would distinguish them from their non-Uralic-speaking neighbours. CONCLUSIONS: We show that most Uralic speakers share a distinct ancestry component of likely Siberian origin, which suggests that the spread of Uralic languages involved at least some demic component.
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Pueblo Asiatico/genética , Población Blanca/genética , Demografía , Genes , Variación Genética , Genoma Humano , Humanos , Lingüística , Dinámica PoblacionalRESUMEN
BACKGROUND: The Parsis are one of the smallest religious communities in the world. To understand the population structure and demographic history of this group in detail, we analyzed Indian and Pakistani Parsi populations using high-resolution genetic variation data on autosomal and uniparental loci (Y-chromosomal and mitochondrial DNA). Additionally, we also assayed mitochondrial DNA polymorphisms among ancient Parsi DNA samples excavated from Sanjan, in present day Gujarat, the place of their original settlement in India. RESULTS: Among present-day populations, the Parsis are genetically closest to Iranian and the Caucasus populations rather than their South Asian neighbors. They also share the highest number of haplotypes with present-day Iranians and we estimate that the admixture of the Parsis with Indian populations occurred ~1,200 years ago. Enriched homozygosity in the Parsi reflects their recent isolation and inbreeding. We also observed 48% South-Asian-specific mitochondrial lineages among the ancient samples, which might have resulted from the assimilation of local females during the initial settlement. Finally, we show that Parsis are genetically closer to Neolithic Iranians than to modern Iranians, who have witnessed a more recent wave of admixture from the Near East. CONCLUSIONS: Our results are consistent with the historically-recorded migration of the Parsi populations to South Asia in the 7th century and in agreement with their assimilation into the Indian sub-continent's population and cultural milieu "like sugar in milk". Moreover, in a wider context our results support a major demographic transition in West Asia due to the Islamic conquest.
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Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Etnicidad/genética , Genética de Población , Emigración e Inmigración , Etnicidad/historia , Femenino , Geografía , Haplotipos , Historia Antigua , Humanos , India , Irán , Pakistán , FilogeniaRESUMEN
Human mitochondrial DNA haplogroup U is among the initial maternal founders in Southwest Asia and Europe and one that best indicates matrilineal genetic continuity between late Pleistocene hunter-gatherer groups and present-day populations of Europe. While most haplogroup U subclades are older than 30 thousand years, the comparatively recent coalescence time of the extant variation of haplogroup U7 (~16-19 thousand years ago) suggests that its current distribution is the consequence of more recent dispersal events, despite its wide geographical range across Europe, the Near East and South Asia. Here we report 267 new U7 mitogenomes that - analysed alongside 100 published ones - enable us to discern at least two distinct temporal phases of dispersal, both of which most likely emanated from the Near East. The earlier one began prior to the Holocene (~11.5 thousand years ago) towards South Asia, while the later dispersal took place more recently towards Mediterranean Europe during the Neolithic (~8 thousand years ago). These findings imply that the carriers of haplogroup U7 spread to South Asia and Europe before the suggested Bronze Age expansion of Indo-European languages from the Pontic-Caspian Steppe region.
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ADN Mitocondrial/genética , Evolución Molecular , Haplotipos/genética , Teorema de Bayes , Geografía , Humanos , Mutación/genética , FilogeniaRESUMEN
BACKGROUND: The neuregulin 1 gene is a susceptibility gene for substance dependence. A functional polymorphism (SNP8NRG243177/rs6994992; C/T) in the promoter region of the brain-specific type IV neuregulin-1 gene ( NRG1) has been associated with psychiatric disorders (e.g. schizophrenia and bipolar disorder) that often present higher odds of smoking, alcohol and illicit drug use. This study assessed the association of the NRG1 genotype with drug use and possible interaction with stressful life events (SLEs). METHODS: The database of the Estonian Children Personality Behaviour and Health Study (beginning in 1998) was used. Cohorts of children initially 9 years old ( n=583; followed up at 15 and 18 years) and 15 years old ( n=593; followed up at 18 and 25 years) provided self-reports on alcohol, tobacco and illicit substance use and SLEs. Psychiatric assessment based on DSM-IV was carried out on the older birth cohort at age 25 to assess the lifetime presence of substance use disorders. NRG1 rs6994992 was genotyped in all participants by TaqMan® Pre-Designed SNP Genotyping Assay on the Applied Biosystems ViiA™ 7 Real-Time PCR System. The minor (T) allele frequency was 0.37. RESULTS: NRG1 rs6994992 C/C homozygotes, especially those who had experienced more SLEs, were more likely to develop alcohol use disorders by young adulthood, were generally more active consumers of tobacco products, and had more likely used illicit drugs. In T allele carriers, SLEs had a negligible effect on substance use. CONCLUSIONS: In humans, NRG1 genotype is associated with substance use, and this relationship is moderated by adverse life events, with a gain-of-function allele being protective.
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Trastorno Bipolar/genética , Drogas Ilícitas/efectos adversos , Neurregulina-1/genética , Polimorfismo de Nucleótido Simple/genética , Esquizofrenia/genética , Estrés Psicológico/genética , Trastornos Relacionados con Sustancias/genética , Adolescente , Adulto , Alelos , Encéfalo/metabolismo , Niño , Estudios de Cohortes , Estonia , Femenino , Estudios de Seguimiento , Frecuencia de los Genes/genética , Genotipo , Humanos , Estudios Longitudinales , Masculino , Regiones Promotoras Genéticas/genéticaRESUMEN
Here we report the Simons Genome Diversity Project data set: high quality genomes from 300 individuals from 142 diverse populations. These genomes include at least 5.8 million base pairs that are not present in the human reference genome. Our analysis reveals key features of the landscape of human genome variation, including that the rate of accumulation of mutations has accelerated by about 5% in non-Africans compared to Africans since divergence. We show that the ancestors of some pairs of present-day human populations were substantially separated by 100,000 years ago, well before the archaeologically attested onset of behavioural modernity. We also demonstrate that indigenous Australians, New Guineans and Andamanese do not derive substantial ancestry from an early dispersal of modern humans; instead, their modern human ancestry is consistent with coming from the same source as that of other non-Africans.
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Variación Genética/genética , Genoma Humano/genética , Genómica , Tasa de Mutación , Filogenia , Grupos Raciales/genética , Animales , Australia , Población Negra/genética , Conjuntos de Datos como Asunto , Genética de Población , Historia Antigua , Migración Humana/historia , Humanos , Nativos de Hawái y Otras Islas del Pacífico/genética , Hombre de Neandertal/genética , Nueva Guinea , Análisis de Secuencia de ADN , Especificidad de la Especie , Factores de TiempoRESUMEN
BACKGROUND: The production of recombinant monoclonal antibodies in mammalian cell culture is of high priority in research and medical fields. A critical step in this process is the isolation of the antigen-binding domain sequences of antibodies possessing the desired properties. Many different techniques have been described to achieve this goal, but all have shortcomings; most techniques have problems with robustness, are time-consuming and costly, or have complications in the transfer from isolation to production phase. Here, we report a novel HybriFree technology for the development of monoclonal antibodies from different species that is robust, rapid, inexpensive and flexible and can be used for the subsequent production of antibodies in mammalian cell factories. RESULTS: HybriFree technology is illustrated herein via detailed examples of isolating mouse, rabbit and chicken monoclonal antibody sequences from immunized animals. Starting from crude spleen samples, antigen capturing of specific B-cells is performed initially. cDNA of antibody variable domains is amplified from the captured cells and used a source material for simple and rapid restriction/ligation free cloning of expression vector library in order to produce scFv-Fc or intact IgG antibodies. The vectors can be directly used for screening purposes as well as for the subsequent production of the developed monoclonal antibodies in mammalian cell culture. The antibodies isolated by the method have been shown to be functional in different immunoassays, including ELISA, immunofluorescence and Western blot. In addition, we demonstrate that by using a modified method including a negative selection step, we can isolate specific antibodies targeting the desired epitope and eliminate antibodies directed to undesired off-targets. CONCLUSIONS: HybriFree can be used for the reliable development of monoclonal antibodies and their subsequent production in mammalian cells. This simple protocol requires neither the culturing of B-cells nor single-cell manipulations, and only standard molecular biology laboratory equipment is needed. In principle, the method is applicable to any species for which antibody cDNA sequence information is available.
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Anticuerpos Monoclonales/inmunología , Linfocitos B/inmunología , Técnicas Citológicas/métodos , Inmunoensayo/métodos , Proteínas Recombinantes/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/metabolismo , Linfocitos B/química , Pollos , ADN Complementario/química , ADN Complementario/genética , Femenino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Biblioteca de Péptidos , Conejos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
In order to explore the diversity and selective signatures of duplication and deletion human copy-number variants (CNVs), we sequenced 236 individuals from 125 distinct human populations. We observed that duplications exhibit fundamentally different population genetic and selective signatures than deletions and are more likely to be stratified between human populations. Through reconstruction of the ancestral human genome, we identify megabases of DNA lost in different human lineages and pinpoint large duplications that introgressed from the extinct Denisova lineage now found at high frequency exclusively in Oceanic populations. We find that the proportion of CNV base pairs to single-nucleotide-variant base pairs is greater among non-Africans than it is among African populations, but we conclude that this difference is likely due to unique aspects of non-African population history as opposed to differences in CNV load.
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Variaciones en el Número de Copia de ADN , Evolución Molecular , Duplicación de Gen , Genoma Humano/genética , Población/genética , Eliminación de Secuencia , Animales , Población Negra/clasificación , Población Negra/genética , Hominidae/genética , Humanos , Nativos de Hawái y Otras Islas del Pacífico/clasificación , Nativos de Hawái y Otras Islas del Pacífico/genética , Filogenia , Polimorfismo de Nucleótido Simple , Selección GenéticaRESUMEN
Prehistoric population structure associated with the transition to an agricultural lifestyle in Europe remains a contentious idea. Population-genomic data from 11 Scandinavian Stone Age human remains suggest that hunter-gatherers had lower genetic diversity than that of farmers. Despite their close geographical proximity, the genetic differentiation between the two Stone Age groups was greater than that observed among extant European populations. Additionally, the Scandinavian Neolithic farmers exhibited a greater degree of hunter-gatherer-related admixture than that of the Tyrolean Iceman, who also originated from a farming context. In contrast, Scandinavian hunter-gatherers displayed no significant evidence of introgression from farmers. Our findings suggest that Stone Age foraging groups were historically in low numbers, likely owing to oscillating living conditions or restricted carrying capacity, and that they were partially incorporated into expanding farming groups.
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Agricultura/historia , ADN Mitocondrial/genética , Variación Genética , Genoma Humano , Población Blanca/genética , ADN Mitocondrial/historia , Genómica , Historia Antigua , Humanos , Países Escandinavos y Nórdicos , Población Blanca/historiaRESUMEN
The northern region of the Indian subcontinent is a vast landscape interlaced by diverse ecologies, for example, the Gangetic Plain and the Himalayas. A great number of ethnic groups are found there, displaying a multitude of languages and cultures. The Tharu is one of the largest and most linguistically diverse of such groups, scattered across the Tarai region of Nepal and bordering Indian states. Their origins are uncertain. Hypotheses have been advanced postulating shared ancestry with Austroasiatic, or Tibeto-Burman-speaking populations as well as aboriginal roots in the Tarai. Several Tharu groups speak a variety of Indo-Aryan languages, but have traditionally been described by ethnographers as representing East Asian phenotype. Their ancestry and intra-population diversity has previously been tested only for haploid (mitochondrial DNA and Y-chromosome) markers in a small portion of the population. This study presents the first systematic genetic survey of the Tharu from both Nepal and two Indian states of Uttarakhand and Uttar Pradesh, using genome-wide SNPs and haploid markers. We show that the Tharu have dual genetic ancestry as up to one-half of their gene pool is of East Asian origin. Within the South Asian proportion of the Tharu genetic ancestry, we see vestiges of their common origin in the north of the South Asian Subcontinent manifested by mitochondrial DNA haplogroup M43.
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Pueblo Asiatico/genética , Etnicidad/genética , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Estudios de Asociación Genética , Variación Genética , Técnicas de Genotipaje , Haplotipos , Humanos , India , Nepal , Filogeografía , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADNRESUMEN
Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups - a profile which is very similar to the two other eastern European populations - Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively.
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Cromosomas Humanos Y , ADN Mitocondrial/genética , Pool de Genes , Población Blanca/genética , Etnicidad/genética , Haplotipos , Humanos , Masculino , Filogenia , Filogeografía , República de BelarúsRESUMEN
The purpose of this study was to investigate the effects of the 5-HTTLPR and brain-derived neurotrophic factor (BDNF) Val66Met polymorphisms on self-reported Big Five personality traits and their facets in a population representative sample of adolescents. The sample consisted of both cohorts of the Estonian Children Personality Behaviour and Health Study, and personality data were collected during its second waves. The 5-HTTLPR and BDNF Val66Met polymorphisms were genotyped. The BDNF Val66Met had a significant effect on conscientiousness [F(1,807)=4.32, P=0.038]. We did not find effects of the 5-HTTLPR polymorphism on the main domains of personality, however, a gene×gene interaction on conscientiousness emerged -BDNF Val66Met Met-allele carriers with the 5-HTTLPR s/s genotype had by far the lowest scores in conscientiousness [F(2,803)=4.38, P=0.012]. In addition, we found genotype effects on some facet scales. In conclusion, the BDNF Val66Met genotype Met-allele carriers have lower conscientiousness, and this effect is increased in the 5-HTTLPR s/s individuals.
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Sustitución de Aminoácidos/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Personalidad/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Adolescente , Alelos , Femenino , Heterocigoto , Homocigoto , Humanos , MasculinoRESUMEN
RATIONALE AND OBJECTIVE: Twin studies suggest that substance use initiation in children and adolescents is determined primarily by environmental influences, whereas the establishment of use patterns is strongly controlled by genetic factors. The present study analysed the effects of the serotonin transporter promoter polymorphism [5-HT transporter gene-linked polymorphic region (5-HTTLPR)] and the α(2A)-adrenoceptor C-1291G genotype (ADRA2A C-1291G) as well as their interaction effects on alcohol, tobacco and drug use from preadolescence to the late adolescence. METHODS: Initial sample of 9-year-old children of Estonian Children Personality Behaviour and Health Study (n = 583) was recalled at ages 15 and 18. Participants reported in all waves how frequently they smoked and used alcohol and illicit drugs. RESULTS: 5-HTTLPR had age-dependent effects on alcohol, tobacco and drug use: substance use did not differ by genotype at age 9, but at age 15, the participants with the short (s)/s genotype had higher tobacco use, and at age 18, they were more active alcohol, drug and tobacco users. Effects of ADRA2A C-1291G on drug use were dependent on gender, age and 5-HTTLPR. Males (age 18) with ADRA2A CG genotype, when compared to other participants, tended to have higher drug use especially when they had s/s genotype of 5-HTTLPR. CONCLUSIONS: Our results reveal that expression of genetic vulnerability for substance use in children and adolescents may depend on age, gender, interaction of genes, and type of substance.
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Receptores Adrenérgicos alfa 2/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Trastornos Relacionados con Sustancias/genética , Adolescente , Factores de Edad , Análisis de Varianza , Niño , Interpretación Estadística de Datos , Estonia/epidemiología , Femenino , Genotipo , Humanos , Estudios Longitudinales , Masculino , Polimorfismo Genético , Factores Sexuales , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/metabolismoRESUMEN
The geographic origin and time of dispersal of Austroasiatic (AA) speakers, presently settled in south and southeast Asia, remains disputed. Two rival hypotheses, both assuming a demic component to the language dispersal, have been proposed. The first of these places the origin of Austroasiatic speakers in southeast Asia with a later dispersal to south Asia during the Neolithic, whereas the second hypothesis advocates pre-Neolithic origins and dispersal of this language family from south Asia. To test the two alternative models, this study combines the analysis of uniparentally inherited markers with 610,000 common single nucleotide polymorphism loci from the nuclear genome. Indian AA speakers have high frequencies of Y chromosome haplogroup O2a; our results show that this haplogroup has significantly higher diversity and coalescent time (17-28 thousand years ago) in southeast Asia, strongly supporting the first of the two hypotheses. Nevertheless, the results of principal component and "structure-like" analyses on autosomal loci also show that the population history of AA speakers in India is more complex, being characterized by two ancestral components-one represented in the pattern of Y chromosomal and EDAR results and the other by mitochondrial DNA diversity and genomic structure. We propose that AA speakers in India today are derived from dispersal from southeast Asia, followed by extensive sex-specific admixture with local Indian populations.
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Emigración e Inmigración , Variación Genética , Genética de Población , Lenguaje , Asia Sudoriental , Cromosomas Humanos Y , ADN Mitocondrial/genética , Humanos , IndiaRESUMEN
Contemporary Jews comprise an aggregate of ethno-religious communities whose worldwide members identify with each other through various shared religious, historical and cultural traditions. Historical evidence suggests common origins in the Middle East, followed by migrations leading to the establishment of communities of Jews in Europe, Africa and Asia, in what is termed the Jewish Diaspora. This complex demographic history imposes special challenges in attempting to address the genetic structure of the Jewish people. Although many genetic studies have shed light on Jewish origins and on diseases prevalent among Jewish communities, including studies focusing on uniparentally and biparentally inherited markers, genome-wide patterns of variation across the vast geographic span of Jewish Diaspora communities and their respective neighbours have yet to be addressed. Here we use high-density bead arrays to genotype individuals from 14 Jewish Diaspora communities and compare these patterns of genome-wide diversity with those from 69 Old World non-Jewish populations, of which 25 have not previously been reported. These samples were carefully chosen to provide comprehensive comparisons between Jewish and non-Jewish populations in the Diaspora, as well as with non-Jewish populations from the Middle East and north Africa. Principal component and structure-like analyses identify previously unrecognized genetic substructure within the Middle East. Most Jewish samples form a remarkably tight subcluster that overlies Druze and Cypriot samples but not samples from other Levantine populations or paired Diaspora host populations. In contrast, Ethiopian Jews (Beta Israel) and Indian Jews (Bene Israel and Cochini) cluster with neighbouring autochthonous populations in Ethiopia and western India, respectively, despite a clear paternal link between the Bene Israel and the Levant. These results cast light on the variegated genetic architecture of the Middle East, and trace the origins of most Jewish Diaspora communities to the Levant.
Asunto(s)
Genoma Humano/genética , Judíos/genética , África del Norte/etnología , Alelos , Asia , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Etiopía/etnología , Europa (Continente) , Genotipo , Geografía , Humanos , India/etnología , Judíos/clasificación , Medio Oriente/etnología , Filogenia , Análisis de Componente PrincipalRESUMEN
BACKGROUND: Human genetic diversity observed in Indian subcontinent is second only to that of Africa. This implies an early settlement and demographic growth soon after the first 'Out-of-Africa' dispersal of anatomically modern humans in Late Pleistocene. In contrast to this perspective, linguistic diversity in India has been thought to derive from more recent population movements and episodes of contact. With the exception of Dravidian, which origin and relatedness to other language phyla is obscure, all the language families in India can be linked to language families spoken in different regions of Eurasia. Mitochondrial DNA and Y chromosome evidence has supported largely local evolution of the genetic lineages of the majority of Dravidian and Indo-European speaking populations, but there is no consensus yet on the question of whether the Munda (Austro-Asiatic) speaking populations originated in India or derive from a relatively recent migration from further East. RESULTS: Here, we report the analysis of 35 novel complete mtDNA sequences from India which refine the structure of Indian-specific varieties of haplogroup R. Detailed analysis of haplogroup R7, coupled with a survey of approximately 12,000 mtDNAs from caste and tribal groups over the entire Indian subcontinent, reveals that one of its more recently derived branches (R7a1), is particularly frequent among Munda-speaking tribal groups. This branch is nested within diverse R7 lineages found among Dravidian and Indo-European speakers of India. We have inferred from this that a subset of Munda-speaking groups have acquired R7 relatively recently. Furthermore, we find that the distribution of R7a1 within the Munda-speakers is largely restricted to one of the sub-branches (Kherwari) of northern Munda languages. This evidence does not support the hypothesis that the Austro-Asiatic speakers are the primary source of the R7 variation. Statistical analyses suggest a significant correlation between genetic variation and geography, rather than between genes and languages. CONCLUSION: Our high-resolution phylogeographic study, involving diverse linguistic groups in India, suggests that the high frequency of mtDNA haplogroup R7 among Munda speaking populations of India can be explained best by gene flow from linguistically different populations of Indian subcontinent. The conclusion is based on the observation that among Indo-Europeans, and particularly in Dravidians, the haplogroup is, despite its lower frequency, phylogenetically more divergent, while among the Munda speakers only one sub-clade of R7, i.e. R7a1, can be observed. It is noteworthy that though R7 is autochthonous to India, and arises from the root of hg R, its distribution and phylogeography in India is not uniform. This suggests the more ancient establishment of an autochthonous matrilineal genetic structure, and that isolation in the Pleistocene, lineage loss through drift, and endogamy of prehistoric and historic groups have greatly inhibited genetic homogenization and geographical uniformity.