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1.
Nature ; 538(7624): 201-206, 2016 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-27654912

RESUMEN

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.


Asunto(s)
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 Tiempo
2.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36430820

RESUMEN

The pathogenic variants of genes encoding proteins, participating in the formation and functioning of epidermis and dermo-epidermal junctions, create a large variety of clinical phenotypes from: small localized to severe generalized dermatitis, as well as early, or even, prenatal death due to extensive epidermis loss. The diagnostic panel in this study was developed for the purposes of identifying these pathogenic genetic variants in 268 Russian children, who possessed the epidermolysis bullosa symptom complex in a selection of 247 families. This panel included the targeted areas of 33 genes, which are genetic variants that can lead to the development of the phenotype mentioned above. The usage of next generation sequencing allowed the revelation of 192 various altered alleles (of which 109 alleles were novel, i.e., had not been described previously). In addition, it allowed the definition of the genetic variants that are both typical for most of the examined children and for the separate ethnic groups inhabiting modern Russia. We found that the most characteristic mutations for the Dargin and Chechen ethnic groups are the c.3577del deletion in the COL7A1 gene and the c.2488G>A missense mutation in the COL17A1 gene, respectively. In addition, the study of haplotypes of microsatellite markers, which we managed to conduct in the Dargin population, confirmed the presence of the founder effect.


Asunto(s)
Epidermólisis Ampollosa , Humanos , Epidermólisis Ampollosa/diagnóstico , Epidermólisis Ampollosa/genética , Alelos , Fenotipo , Mutación , Secuenciación de Nucleótidos de Alto Rendimiento , Colágeno Tipo VII/genética
3.
J Hum Genet ; 66(7): 707-716, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33510364

RESUMEN

Western Kazakhstan is populated by three clans totaling 2 million people. Since the clans are patrilineal, the Y-chromosome is the most informative genetic system for tracing their origin. We genotyped 40 Y-SNP and 17 Y-STR markers in 330 Western Kazakhs. High phylogenetic resolution within haplogroup C2a1a2-M48 was achieved by using additional SNPs. Three lines of evidence indicate that the Alimuly and Baiuly clans (but not the Zhetiru clan) have a common founder placed 700 ± 200 years back by the STR data and 500 ± 200 years back by the sequencing data. This supports traditional genealogy claims about the descent of these clans from Emir Alau, who lived 650 years ago and whose lineage might be carried by two-thirds of Western Kazakhs. There is accumulation of specific haplogroups in the subclans representing other lineages, confirming that the clan structure corresponds with the paternal genetic structure of the steppe population.


Asunto(s)
Cromosomas Humanos Y/genética , Genealogía y Heráldica , Haplotipos/genética , Filogenia , Efecto Fundador , Genotipo , Humanos , Kazajstán/epidemiología , Masculino , Polimorfismo de Nucleótido Simple/genética
4.
BMC Genomics ; 21(Suppl 7): 527, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32912208

RESUMEN

BACKGROUND: Predicting the eye and hair color from genotype became an established and widely used tool in forensic genetics, as well as in studies of ancient human populations. However, the accuracy of this tool has been verified on the West and Central Europeans only, while populations from border regions between Europe and Asia (like Caucasus and Ural) also carry the light pigmentation phenotypes. RESULTS: We phenotyped 286 samples collected across North Eurasia, genotyped them by the standard HIrisPlex-S markers and found that predictive power in Caucasus/Ural/West Siberian populations is reasonable but lower than that in West Europeans. As these populations have genetic ancestries different from that of West Europeans, we hypothesized they may carry a somewhat different allele spectrum. Thus, for all samples we performed the exome sequencing additionally enriched with the 53 genes and intergenic regions known to be associated with the eye/hair color. Our association analysis replicated the importance of the key previously known SNPs but also identified five new markers whose eye color prediction power for the studied populations is compatible with the two major previously well-known SNPs. Four out of these five SNPs lie within the HERС2 gene and the fifth in the intergenic region. These SNPs are found at high frequencies in most studied populations. The released dataset of exomes from Russian populations can be further used for population genetic and medical genetic studies. CONCLUSIONS: This study demonstrated that precision of the established systems for eye/hair color prediction from a genotype is slightly lower for the populations from the border regions between Europe and Asia that for the West Europeans. However, this precision can be improved if some newly revealed predictive SNPs are added into the panel. We discuss that the replication of these pigmentation-associated SNPs on the independent North Eurasian sample is needed in the future studies.


Asunto(s)
ADN , Color del Cabello , Asia , Europa (Continente) , Color del Ojo/genética , Humanos , Polimorfismo de Nucleótido Simple , Federación de Rusia
5.
BMC Genet ; 21(Suppl 1): 87, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-33092538

RESUMEN

BACKGROUND: The majority of the Kazakhs from South Kazakhstan belongs to the 12 clans of the Senior Zhuz. According to traditional genealogy, nine of these clans have a common ancestor and constitute the Uissun tribe. There are three main hypotheses of the clans' origin, namely, origin from early Wusuns, from Niru'un Mongols, or from Darligin Mongols. We genotyped 490 samples of South Kazakhs by 35 Y-chromosomal SNPs (single nucleotide polymorphism) and 17 STRs (short tandem repeat). Additionally, 133 samples from citizen science projects were included into the study. RESULTS: We found that three Uissun clans have unique Y-chromosomal profiles, but the remaining six Uissun clans and one non-Uissun clan share a common paternal gene pool. They share a high frequency (> 40%) of the C2*-ST haplogroup (marked by the SNP F3796), which is associated with the early Niru'un Mongols. Phylogenetic analysis of this haplogroup carried out on 743 individuals from 25 populations of Eurasia has revealed a set of haplotype clusters, three of which contain the Uissun haplotypes. The demographic expansion of these clusters dates back to the 13-fourteenth century, coinciding with the time of the Uissun's ancestor Maiky-biy known from historical sources. In addition, it coincides with the expansion period of the Mongol Empire in the Late Middle Ages. A comparison of the results with published aDNA (ancient deoxyribonucleic acid) data and modern Y haplogroups frequencies suggest an origin of Uissuns from Niru'un Mongols rather than from Wusuns or Darligin Mongols. CONCLUSIONS: The Y-chromosomal variation in South Kazakh clans indicates their common origin in 13th-14th centuries AD, in agreement with the traditional genealogy. Though genetically there were at least three ancestral lineages instead of the traditional single ancestor. The majority of the Y-chromosomal lineages of South Kazakhstan was brought by the migration of the population related to the medieval Niru'un Mongols.


Asunto(s)
Pueblo Asiatico/genética , Cromosomas Humanos Y/genética , Genética de Población , Etnicidad/genética , Pool de Genes , Genotipo , Haplotipos , Humanos , Kazajstán , Masculino , Repeticiones de Microsatélite , Mongolia , Filogenia , Polimorfismo de Nucleótido Simple
6.
Nature ; 505(7481): 87-91, 2014 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-24256729

RESUMEN

The origins of the First Americans remain contentious. Although Native Americans seem to be genetically most closely related to east Asians, there is no consensus with regard to which specific Old World populations they are closest to. Here we sequence the draft genome of an approximately 24,000-year-old individual (MA-1), from Mal'ta in south-central Siberia, to an average depth of 1×. To our knowledge this is the oldest anatomically modern human genome reported to date. The MA-1 mitochondrial genome belongs to haplogroup U, which has also been found at high frequency among Upper Palaeolithic and Mesolithic European hunter-gatherers, and the Y chromosome of MA-1 is basal to modern-day western Eurasians and near the root of most Native American lineages. Similarly, we find autosomal evidence that MA-1 is basal to modern-day western Eurasians and genetically closely related to modern-day Native Americans, with no close affinity to east Asians. This suggests that populations related to contemporary western Eurasians had a more north-easterly distribution 24,000 years ago than commonly thought. Furthermore, we estimate that 14 to 38% of Native American ancestry may originate through gene flow from this ancient population. This is likely to have occurred after the divergence of Native American ancestors from east Asian ancestors, but before the diversification of Native American populations in the New World. Gene flow from the MA-1 lineage into Native American ancestors could explain why several crania from the First Americans have been reported as bearing morphological characteristics that do not resemble those of east Asians. Sequencing of another south-central Siberian, Afontova Gora-2 dating to approximately 17,000 years ago, revealed similar autosomal genetic signatures as MA-1, suggesting that the region was continuously occupied by humans throughout the Last Glacial Maximum. Our findings reveal that western Eurasian genetic signatures in modern-day Native Americans derive not only from post-Columbian admixture, as commonly thought, but also from a mixed ancestry of the First Americans.


Asunto(s)
Pueblo Asiatico/genética , Genoma Humano/genética , Indígenas Norteamericanos/etnología , Indígenas Norteamericanos/genética , Filogenia , Población Blanca/genética , Animales , Asia/etnología , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Emigración e Inmigración , Flujo Génico/genética , Genoma Mitocondrial/genética , Haplotipos/genética , Humanos , Indígenas Norteamericanos/clasificación , Masculino , Filogeografía , Siberia/etnología , Esqueleto
7.
Nature ; 513(7518): 409-13, 2014 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-25230663

RESUMEN

We sequenced the genomes of a ∼7,000-year-old farmer from Germany and eight ∼8,000-year-old hunter-gatherers from Luxembourg and Sweden. We analysed these and other ancient genomes with 2,345 contemporary humans to show that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians, who contributed to both Europeans and Near Easterners; and early European farmers, who were mainly of Near Eastern origin but also harboured west European hunter-gatherer related ancestry. We model these populations' deep relationships and show that early European farmers had ∼44% ancestry from a 'basal Eurasian' population that split before the diversification of other non-African lineages.


Asunto(s)
Genoma Humano/genética , Población Blanca/clasificación , Población Blanca/genética , Agricultura/historia , Asia/etnología , Europa (Continente) , Historia Antigua , Humanos , Dinámica Poblacional , Análisis de Componente Principal , Recursos Humanos
8.
Am J Hum Genet ; 99(1): 163-73, 2016 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-27392075

RESUMEN

The paternal haplogroup (hg) N is distributed from southeast Asia to eastern Europe. The demographic processes that have shaped the vast extent of this major Y chromosome lineage across numerous linguistically and autosomally divergent populations have previously been unresolved. On the basis of 94 high-coverage re-sequenced Y chromosomes, we establish and date a detailed hg N phylogeny. We evaluate geographic structure by using 16 distinguishing binary markers in 1,631 hg N Y chromosomes from a collection of 6,521 samples from 56 populations. The more southerly distributed sub-clade N4 emerged before N2a1 and N3, found mostly in the north, but the latter two display more elaborate branching patterns, indicative of regional contrasts in recent expansions. In particular, a number of prominent and well-defined clades with common N3a3'6 ancestry occur in regionally dissimilar northern Eurasian populations, indicating almost simultaneous regional diversification and expansion within the last 5,000 years. This patrilineal genetic affinity is decoupled from the associated higher degree of language diversity.


Asunto(s)
Cromosomas Humanos Y/genética , Haplotipos/genética , Lenguaje , Asia , Europa (Continente) , Humanos , Filogeografía , Factores de Tiempo
9.
PLoS Genet ; 11(4): e1005068, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25898006

RESUMEN

The Turkic peoples represent a diverse collection of ethnic groups defined by the Turkic languages. These groups have dispersed across a vast area, including Siberia, Northwest China, Central Asia, East Europe, the Caucasus, Anatolia, the Middle East, and Afghanistan. The origin and early dispersal history of the Turkic peoples is disputed, with candidates for their ancient homeland ranging from the Transcaspian steppe to Manchuria in Northeast Asia. Previous genetic studies have not identified a clear-cut unifying genetic signal for the Turkic peoples, which lends support for language replacement rather than demic diffusion as the model for the Turkic language's expansion. We addressed the genetic origin of 373 individuals from 22 Turkic-speaking populations, representing their current geographic range, by analyzing genome-wide high-density genotype data. In agreement with the elite dominance model of language expansion most of the Turkic peoples studied genetically resemble their geographic neighbors. However, western Turkic peoples sampled across West Eurasia shared an excess of long chromosomal tracts that are identical by descent (IBD) with populations from present-day South Siberia and Mongolia (SSM), an area where historians center a series of early Turkic and non-Turkic steppe polities. While SSM matching IBD tracts (> 1cM) are also observed in non-Turkic populations, Turkic peoples demonstrate a higher percentage of such tracts (p-values ≤ 0.01) compared to their non-Turkic neighbors. Finally, we used the ALDER method and inferred admixture dates (~9th-17th centuries) that overlap with the Turkic migrations of the 5th-16th centuries. Thus, our results indicate historical admixture among Turkic peoples, and the recent shared ancestry with modern populations in SSM supports one of the hypothesized homelands for their nomadic Turkic and related Mongolic ancestors.


Asunto(s)
Cromosomas/genética , Flujo Génico , Genética de Población , Migración Humana/historia , Asia , Pueblo Asiatico/genética , Pueblo Asiatico/historia , China , Cromosomas Humanos Y/genética , Etnicidad/genética , Etnicidad/historia , Europa (Continente) , Genotipo , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia Medieval , Humanos , Lenguaje , Medio Oriente , Mongolia , Polimorfismo de Nucleótido Simple/genética , Siberia
10.
BMC Evol Biol ; 17(Suppl 1): 18, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28251872

RESUMEN

BACKGROUND: The Y-chromosome haplogroup Q has three major branches: Q1, Q2, and Q3. Q1 is found in both Asia and the Americas where it accounts for about 90% of indigenous Native American Y-chromosomes; Q2 is found in North and Central Asia; but little is known about the third branch, Q3, also named Q1b-L275. Here, we combined the efforts of population geneticists and genetic genealogists to use the potential of full Y-chromosome sequencing for reconstructing haplogroup Q3 phylogeography and suggest possible linkages to events in population history. RESULTS: We analyzed 47 fully sequenced Y-chromosomes and reconstructed the haplogroup Q3 phylogenetic tree in detail. Haplogroup Q3-L275, derived from the oldest known split within Eurasian/American haplogroup Q, most likely occurred in West or Central Asia in the Upper Paleolithic period. During the Mesolithic and Neolithic epochs, Q3 remained a minor component of the West Asian Y-chromosome pool and gave rise to five branches (Q3a to Q3e), which spread across West, Central and parts of South Asia. Around 3-4 millennia ago (Bronze Age), the Q3a branch underwent a rapid expansion, splitting into seven branches, some of which entered Europe. One of these branches, Q3a1, was acquired by a population ancestral to Ashkenazi Jews and grew within this population during the 1st millennium AD, reaching up to 5% in present day Ashkenazi. CONCLUSIONS: This study dataset was generated by a massive Y-chromosome genotyping effort in the genetic genealogy community, and phylogeographic patterns were revealed by a collaboration of population geneticists and genetic genealogists. This positive experience of collaboration between academic and citizen science provides a model for further joint projects. Merging data and skills of academic and citizen science promises to combine, respectively, quality and quantity, generalization and specialization, and achieve a well-balanced and careful interpretation of the paternal-side history of human populations.


Asunto(s)
Cromosomas Humanos Y , Genética de Población , Asia , Colaboración de las Masas , Etnicidad/genética , Europa (Continente) , Ligamiento Genético , Haplotipos , Humanos , Masculino , Filogeografía
11.
J Hum Genet ; 62(8): 789-795, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28405014

RESUMEN

Although mutations in the GJB2 gene sequence make up the majority of variants causing autosomal-recessive non-syndromic hearing loss, few large deletions have been shown to contribute to DFNB1 deafness. Currently, genetic testing for DFNB1 hearing loss includes GJB2 sequencing and DFNB1 deletion analysis for two common large deletions, del(GJB6-D13S1830) and del(GJB6-D13S1854). Here, we report frequency in Russia, clinical significance and evolutionary origins of a 101 kb deletion, del(GJB2-D13S175), recently identified by us. In multiethnic cohort of 1104 unrelated hearing loss patients with biallelic mutations at the DFNB1 locus, the del(GJB2-D13S175) allele frequency of up to 0.5% (11/2208) was determined and this allele was shown to be predominantly associated with profound sensorineural hearing loss. Additionally, eight previously unpublished GJB2 mutations were described in this study. All patients carrying del(GJB2-D13S175) were of the Ingush ancestry. Among normal hearing individuals, del(GJB2-D13S175) was observed in Russian Republic of Ingushetia with a carrier rate of ~1% (2/241). Analysis of haplotypes associated with the deletion revealed a common founder in the Ingushes, with age of the deletion being ~3000 years old. Since del(GJB2-D13S175) was missed by standard methods of GJB2 analysis, del(GJB2-D13S175) detection has been added to our routine testing strategy for DFNB1 hearing loss.


Asunto(s)
Conexinas/genética , Efecto Fundador , Pérdida Auditiva/genética , Mutación , Eliminación de Secuencia , Niño , Preescolar , Estudios de Cohortes , Conexina 26 , Femenino , Frecuencia de los Genes , Pruebas Genéticas , Genotipo , Pérdida Auditiva/epidemiología , Humanos , Masculino , Federación de Rusia/epidemiología
12.
PLoS Genet ; 9(2): e1003296, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23459685

RESUMEN

North East Europe harbors a high diversity of cultures and languages, suggesting a complex genetic history. Archaeological, anthropological, and genetic research has revealed a series of influences from Western and Eastern Eurasia in the past. While genetic data from modern-day populations is commonly used to make inferences about their origins and past migrations, ancient DNA provides a powerful test of such hypotheses by giving a snapshot of the past genetic diversity. In order to better understand the dynamics that have shaped the gene pool of North East Europeans, we generated and analyzed 34 mitochondrial genotypes from the skeletal remains of three archaeological sites in northwest Russia. These sites were dated to the Mesolithic and the Early Metal Age (7,500 and 3,500 uncalibrated years Before Present). We applied a suite of population genetic analyses (principal component analysis, genetic distance mapping, haplotype sharing analyses) and compared past demographic models through coalescent simulations using Bayesian Serial SimCoal and Approximate Bayesian Computation. Comparisons of genetic data from ancient and modern-day populations revealed significant changes in the mitochondrial makeup of North East Europeans through time. Mesolithic foragers showed high frequencies and diversity of haplogroups U (U2e, U4, U5a), a pattern observed previously in European hunter-gatherers from Iberia to Scandinavia. In contrast, the presence of mitochondrial DNA haplogroups C, D, and Z in Early Metal Age individuals suggested discontinuity with Mesolithic hunter-gatherers and genetic influx from central/eastern Siberia. We identified remarkable genetic dissimilarities between prehistoric and modern-day North East Europeans/Saami, which suggests an important role of post-Mesolithic migrations from Western Europe and subsequent population replacement/extinctions. This work demonstrates how ancient DNA can improve our understanding of human population movements across Eurasia. It contributes to the description of the spatio-temporal distribution of mitochondrial diversity and will be of significance for future reconstructions of the history of Europeans.


Asunto(s)
ADN Mitocondrial/genética , Flujo Génico , Variación Genética , Genoma Mitocondrial , Arqueología , Europa (Continente) , Genética de Población , Genotipo , Haplotipos , Humanos , Dinámica Poblacional , Federación de Rusia , Países Escandinavos y Nórdicos , Siberia , Población Blanca/genética
13.
BMC Res Notes ; 17(1): 187, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970104

RESUMEN

OBJECTIVE: This study assesses the accuracy of the IrisPlex system, a genetic eye color prediction tool for forensic analysis, in the Kazakh population. The study compares previously published genotypes of 515 Kazakh individuals from varied geographical and ethnohistorical contexts with phenotypic data on their eye color, introduced for the first time in this research. RESULTS: The IrisPlex panel's effectiveness in predicting eye color in the Kazakh population was validated. It exhibited slightly lower accuracy than in Western European populations but was higher than in Siberian populations. The sensitivity was notably high for brown-eyed individuals (0.99), but further research is needed for blue and intermediate eye colors. This study establishes IrisPlex as a useful predictive tool in the Kazakh population and provides a basis for future investigations into the genetic basis of phenotypic variations in this diverse population.


Asunto(s)
Color del Ojo , Humanos , Color del Ojo/genética , Variación Genética , Genética de Población , Genotipo , Kazajstán , Fenotipo , Pueblo de Asia Central/genética
14.
BMC Res Notes ; 17(1): 51, 2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38369539

RESUMEN

OBJECTIVES: The collection of genotype data was conducted as an essential part of a pivotal research project with the goal of examining the genetic variability of skin, hair, and iris color among the Kazakh population. The data has practical application in the field of forensic DNA phenotyping (FDA). Due to the limited size of forensic databases from Central Asia (Kazakhstan), it is practically impossible to obtain an individual identification result based on forensic profiling of short tandem repeats (STRs). However, the pervasive use of the FDA necessitates validation of the currently employed set of genetic markers in a variety of global populations. No such data existed for the Kazakhs. The Phenotype Expert kit (DNA Research Center, LLC, Russia) was used for the first time in this study to collect data. DATA DESCRIPTION: The present study provides genotype data for a total of 60 SNP genetic markers, which were analyzed in a sample of 515 ethnic Kazakhs. The dataset comprises a total of 41 single nucleotide polymorphisms (SNPs) obtained from the HIrisPlex-S panel. Additionally, there are 4 SNPs specifically related to the AB0 gene, 1 marker associated with the AMELX/Y genes, and 14 SNPs corresponding to the primary haplogroups of the Y chromosome. The aforementioned data could prove valuable to researchers with an interest in investigating genetic variability and making predictions about phenotype based on eye color, hair color, skin color, AB0 blood group, gender, and biogeographic origin within the male lineage.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Pueblo de Asia Central , Cromosomas Humanos Y , Haplotipos , Pigmentación , Humanos , Masculino , Sistema del Grupo Sanguíneo ABO/genética , Pueblo de Asia Central/genética , Cromosomas Humanos Y/genética , ADN/genética , Marcadores Genéticos , Genética de Población , Genotipo , Cabello , Haplotipos/genética , Polimorfismo de Nucleótido Simple/genética , Pigmentación de la Piel/genética , Pigmentación/genética , Variación Genética/genética
15.
Mol Biol Evol ; 29(1): 25-30, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21890475

RESUMEN

The information left by recombination in our genomes can be used to make inferences on our recent evolutionary history. Specifically, the number of past recombination events in a population sample is a function of its effective population size (Ne). We have applied a method, Identifying Recombination in Sequences (IRiS), to detect specific past recombination events in 30 Old World populations to infer their Ne. We have found that sub-Saharan African populations have an Ne that is approximately four times greater than those of non-African populations and that outside of Africa, South Asian populations had the largest Ne. We also observe that the patterns of recombinational diversity of these populations correlate with distance out of Africa if that distance is measured along a path crossing South Arabia. No such correlation is found through a Sinai route, suggesting that anatomically modern humans first left Africa through the Bab-el-Mandeb strait rather than through present Egypt.


Asunto(s)
Evolución Molecular , Densidad de Población , Grupos Raciales/genética , Grupos Raciales/historia , Recombinación Genética , África , Asia , Bases de Datos Genéticas , Europa (Continente) , Historia Antigua , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Estadísticas no Paramétricas
16.
PLoS Biol ; 8(11): e1000536, 2010 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-21085689

RESUMEN

In Europe, the Neolithic transition (8,000-4,000 B.C.) from hunting and gathering to agricultural communities was one of the most important demographic events since the initial peopling of Europe by anatomically modern humans in the Upper Paleolithic (40,000 B.C.). However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. To date, inferences about the genetic make up of past populations have mostly been drawn from studies of modern-day Eurasian populations, but increasingly ancient DNA studies offer a direct view of the genetic past. We genetically characterized a population of the earliest farming culture in Central Europe, the Linear Pottery Culture (LBK; 5,500-4,900 calibrated B.C.) and used comprehensive phylogeographic and population genetic analyses to locate its origins within the broader Eurasian region, and to trace potential dispersal routes into Europe. We cloned and sequenced the mitochondrial hypervariable segment I and designed two powerful SNP multiplex PCR systems to generate new mitochondrial and Y-chromosomal data from 21 individuals from a complete LBK graveyard at Derenburg Meerenstieg II in Germany. These results considerably extend the available genetic dataset for the LBK (n = 42) and permit the first detailed genetic analysis of the earliest Neolithic culture in Central Europe (5,500-4,900 calibrated B.C.). We characterized the Neolithic mitochondrial DNA sequence diversity and geographical affinities of the early farmers using a large database of extant Western Eurasian populations (n = 23,394) and a wide range of population genetic analyses including shared haplotype analyses, principal component analyses, multidimensional scaling, geographic mapping of genetic distances, and Bayesian Serial Simcoal analyses. The results reveal that the LBK population shared an affinity with the modern-day Near East and Anatolia, supporting a major genetic input from this area during the advent of farming in Europe. However, the LBK population also showed unique genetic features including a clearly distinct distribution of mitochondrial haplogroup frequencies, confirming that major demographic events continued to take place in Europe after the early Neolithic.


Asunto(s)
Agricultura , ADN Mitocondrial/genética , Emigración e Inmigración , Fósiles , Europa (Continente) , Humanos
17.
Am J Phys Anthropol ; 152(4): 543-50, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24122717

RESUMEN

The area of what is now the Ukraine has been the arena of large-scale demographic processes that may have left their traces in the contemporary gene pool of Ukrainians. In this study, we present new mitochondrial DNA data for 607 Ukrainians (hypervariable segment I sequences and coding region polymorphisms). To study the maternal affinities of Ukrainians at the level of separate mitochondrial haplotypes, we apply an original technique, the haplotype co-occurrence analysis. About 20% of the Ukrainian maternal gene pool is represented by lineages highly specific to Ukrainians, but is scarcely found in other populations. About 9% of Ukrainian mtDNA lineages are typical for peoples of the Volga region. We also identified minor gene pool strata (1.6-3.3%), each of which is common in Lithuanians, Estonians, Saami, Nenets, Cornish, and the populations of the North Caucasus.


Asunto(s)
ADN Mitocondrial/genética , Población Blanca , Antropología Física , Genética de Población , Haplotipos/genética , Humanos , Filogeografía , Ucrania , Población Blanca/clasificación , Población Blanca/genética
18.
Int J Circumpolar Health ; 82(1): 2183931, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36880131

RESUMEN

In order to be digested, the disaccharide trehalose needs to be cleaved by the trehalase enzyme. There were reports suggesting that trehalase deficiency was more common in high-latitude than in the temperate climate populations. New horizons were opened for the epidemiologic research of trehalase enzymopathy when it became clear that reduced trehalase activity is determined by the A allele of tTREH gene (rs2276064). The aim of this study was to analyze the frequencies of the trehalase gene alleles and genotypes among the indigenous peoples of Siberia and the Russian Far East. We genotyped 567 samples representing the indigenous peoples of Siberia and the Russian Far East and 146 samples representing Eastern Slavs as the reference dataset. We found that the frequencies of the A*TREH alleles increased to the east. The A*TREH allele frequency was 0.03 in the reference group, 0.13-0.26 in the North-West Siberian indigenous populations, 0.29-0.30 in the South Siberia, 0.43 in West Siberia, and 0.46 in the low Amur populations. The highest frequency of the A allele (0.63) was observed in the Chukchi and Koryak populations. From 1 to 5% of European origin individuals are at risk of trehalase enzymopathy. In the indigenous populations, the frequency of the A*TREH allele varies 13% to 63%, whereas the frequency of the AA*TREH genotype from 3% to 39%. Thus, the total risk of trehalase enzymopathy among the homo- and heterozygous carriers of the A*TREH allele in the studied indigenous populations may be as high as 24% to 86%.


Asunto(s)
Trehalasa , Humanos , Siberia/epidemiología , Trehalasa/genética , Prevalencia , Federación de Rusia/epidemiología , Asia Oriental
19.
Genes (Basel) ; 14(9)2023 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-37761920

RESUMEN

The gene pool of the East Caucasus, encompassing modern-day Azerbaijan and Dagestan populations, was studied alongside adjacent populations using 83 Y-chromosome SNP markers. The analysis of genetic distances among 18 populations (N = 2216) representing Nakh-Dagestani, Altaic, and Indo-European language families revealed the presence of three components (Steppe, Iranian, and Dagestani) that emerged in different historical periods. The Steppe component occurs only in Karanogais, indicating a recent medieval migration of Turkic-speaking nomads from the Eurasian steppe. The Iranian component is observed in Azerbaijanis, Dagestani Tabasarans, and all Iranian-speaking peoples of the Caucasus. The Dagestani component predominates in Dagestani-speaking populations, except for Tabasarans, and in Turkic-speaking Kumyks. Each component is associated with distinct Y-chromosome haplogroup complexes: the Steppe includes C-M217, N-LLY22g, R1b-M73, and R1a-M198; the Iranian includes J2-M172(×M67, M12) and R1b-M269; the Dagestani includes J1-Y3495 lineages. We propose J1-Y3495 haplogroup's most common lineage originated in an autochthonous ancestral population in central Dagestan and splits up ~6 kya into J1-ZS3114 (Dargins, Laks, Lezgi-speaking populations) and J1-CTS1460 (Avar-Andi-Tsez linguistic group). Based on the archeological finds and DNA data, the analysis of J1-Y3495 phylogeography suggests the growth of the population in the territory of modern-day Dagestan that started in the Bronze Age, its further dispersal, and the microevolution of the diverged population.


Asunto(s)
Pool de Genes , Cromosoma Y , Humanos , Irán , Haplotipos , Filogeografía
20.
Genes (Basel) ; 14(3)2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36980891

RESUMEN

Pusa sibirica, the Baikal seal, is the only extant, exclusively freshwater, pinniped species. The pending issue is, how and when they reached their current habitat-the rift lake Baikal, more than three thousand kilometers away from the Arctic Ocean. To explore the demographic history and genetic diversity of this species, we generated a de novo chromosome-length assembly, and compared it with three closely related marine pinniped species. Multiple whole genome alignment of the four species compared with their karyotypes showed high conservation of chromosomal features, except for three large inversions on chromosome VI. We found the mean heterozygosity of the studied Baikal seal individuals was relatively low (0.61 SNPs/kbp), but comparable to other analyzed pinniped samples. Demographic reconstruction of seals revealed differing trajectories, yet remarkable variations in Ne occurred during approximately the same time periods. The Baikal seal showed a significantly more severe decline relative to other species. This could be due to the difference in environmental conditions encountered by the earlier populations of Baikal seals, as ice sheets changed during glacial-interglacial cycles. We connect this period to the time of migration to Lake Baikal, which occurred ~3-0.3 Mya, after which the population stabilized, indicating balanced habitat conditions.


Asunto(s)
Lagos , Phocidae , Animales , Phocidae/genética , Cariotipo
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