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1.
J Hum Genet ; 68(10): 705-712, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37316650

RESUMO

Due to the geographical proximity of the northern coast of the Sea of Okhotsk and Kamchatka Peninsula to the Beringia, the indigenous populations of these territories are of great interest for elucidating the human settlement history of northern Asia and America. Meanwhile, there is a clear shortage of genetic studies of the indigenous populations of the northern coast of the Sea of Okhotsk. Here, in order to examine their fine-scale matrilineal genetic structure, ancestry and relationships with neighboring populations, we analyzed 203 complete mitogenomes (174 of which are new) from population samples of the Koryaks and Evens of the northern coast of the Sea of Okhotsk and the Chukchi of the extreme northeast Asia. The patterns observed underscore the reduced level of genetic diversity found in the Koryak, Even, and Chukchi populations, which, along with the high degree of interpopulation differentiation, may be the result of genetic drift. Our phylogeographic analysis reveals common Paleo-Asiatic ancestry for 51.1% of the Koryaks and 17.8% of the Evens. About third of the mitogenomes found in the Koryaks and Evens might be considered as ethno-specific, as these are virtually absent elsewhere in North, Central and East Asia. Coalescence ages of most of these lineages coincide well with the emergence and development of the Tokarev and Old Koryak archaeological cultures associated with the formation of the Koryaks, as well as with the period of separation and split of the North Tungusic groups migrated northwards from the Lake Baikal or the Amur River area.


Assuntos
DNA Mitocondrial , Genômica , População da Ásia Setentrional , Humanos , DNA Mitocondrial/genética , Variação Genética/genética , População da Ásia Setentrional/etnologia , População da Ásia Setentrional/genética , Filogeografia , Povos Indígenas/genética
2.
Mol Genet Genomics ; 297(1): 47-62, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34757478

RESUMO

Here, we present a comprehensive data set of 489 complete mitogenomes (211 of which are new) from four Mongolic-speaking populations (Mongols, Barghuts, Khamnigans, and Buryats) to investigate their matrilineal genetic structure, ancestry and relationship with other ethnic groups. We show that along with very high levels of genetic diversity and lack of genetic differentiation, Mongolic-speaking populations exhibit strong genetic resemblance to East Asian populations of Chinese, Japanese, and Uyghurs. Phylogeographic analysis of complete mitogenomes reveals the presence of different components in the gene pools of modern Mongolic-speaking populations-the main East Eurasian component is represented by mtDNA lineages of East Asian, Siberian and autochthonous (the Baikal region/Mongolian) ancestry, whereas the less pronounced West Eurasian component can be ascribed to Europe and West Asia/Caucasus. We also observed that up to one third of the mtDNA subhaplogroups identified in Mongolic-speaking populations can be considered as Mongolic-specific with the coalescence age of most of them not exceeding 1.7 kya. This coincides well with the population size growth which started around 1.1 kya and is detectable only in the Bayesian Skyline Plot constructed based on Mongolic-specific mitogenomes. Our data suggest that the genetic structure established during the Mongol empire is still retained in present-day Mongolic-speaking populations.


Assuntos
DNA Mitocondrial/genética , Etnicidade/genética , Povo Asiático/etnologia , Povo Asiático/genética , Teorema de Bayes , DNA Mitocondrial/análise , Pool Gênico , Variação Genética , Genética Populacional , Genômica/métodos , Haplótipos , Humanos , Idioma , Mongólia/epidemiologia , Mongólia/etnologia , Filogenia , Filogeografia
3.
Cytotherapy ; 23(9): 820-832, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34217618

RESUMO

BACKGROUND AIMS: T cells engineered with synthetic receptors have delivered powerful therapeutic results for patients with relapsed/refractory hematologic malignancies. The authors have recently described the T-cell antigen coupler (TAC) receptor, which co-opts the endogenous T-cell receptor (TCR) and activates engineered T cells in an HLA-independent manner. Here the authors describe the evolution of a next-generation TAC receptor with a focus on developing a TAC-engineered T cell for multiple myeloma. METHODS: To optimize the TAC scaffold, the authors employed a bona fide antigen-binding domain derived from the B-cell maturation antigen-specific monoclonal antibody C11D5.3, which has been used successfully in the clinic. The authors first tested humanized versions of the UCHT1 domain, which is used by the TAC to co-opt the TCR. The authors further discovered that the signal peptide affected surface expression of the TAC receptor. Higher density of the TAC receptor enhanced target binding in vitro, which translated into higher levels of Lck at the immunological synapse and stronger proliferation when only receptor-ligand interactions were present. RESULTS: The authors observed that the humanized UCHT1 improved surface expression and in vivo efficacy. Using TAC T cells derived from both healthy donors and multiple myeloma patients, the authors determined that despite the influence of receptor density on early activation events and effector function, receptor density did not impact late effector functions in vitro, nor did the receptor density affect in vivo efficacy. CONCLUSIONS: The modifications to the TAC scaffold described herein represent an important step in the evolution of this technology, which tolerates a range of expression levels without impacting therapeutic efficacy.


Assuntos
Antígeno de Maturação de Linfócitos B , Mieloma Múltiplo , Humanos , Imunoterapia Adotiva , Mieloma Múltiplo/terapia , Recidiva Local de Neoplasia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T
4.
Mol Ther Oncolytics ; 17: 278-292, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32368616

RESUMO

Tumor-targeted chimeric antigen receptor (CAR)-engineered T lymphocytes (CAR-T cells) have demonstrated striking clinical success, but their use has been associated with a constellation of toxicities. A better understanding of the pathogenesis of these toxicities is required to improve the safety profile of CAR-T cells. Herein, we describe a xenograft model of off-tumor CAR-T cell-associated toxicity. Human CAR-T cells targeted against HER2 using a small-protein binding domain induced acute, dose-dependent toxicities in mice. The inclusion of a CD28 or 4-1BB co-stimulatory domain in the CAR was required to produce toxicity; however, co-stimulation through CD28 was most toxic on a per-cell basis. CAR-T cell activation in the lungs and heart was associated with a systemic cytokine storm. The severity of observed toxicities was dependent upon the peripheral blood mononuclear cell (PBMC) donor used as a T cell source and paralleled the CD4+-to-CD8+ T cell ratio in the adoptive transfer product. CD4+ CAR-T cells were determined to be the primary contributors to CAR-T cell-associated toxicity. However, donor-specific differences persisted after infusion of a purified CD4+ CAR-T cell product, indicating a role for additional variables. This work highlights the contributions of CAR-T cell-intrinsic variables to the pathogenesis of off-tumor toxicity.

5.
Mol Genet Genomics ; 294(6): 1547-1559, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31372716

RESUMO

Distinctive peculiarities of Armenians such as their millennia-long genetic isolation and strong national identity attract a keen interest while studying the demographic history of the West Asia. Here, to examine their fine-scale matrilineal genetic structure, ancestry and relationships with neighboring populations, we analyzed 536 complete mitogenomes (141 of which are novel) from 8 geographically different Armenian populations, covering the whole stretch of historical Armenia. The observed patterns highlight a remarkable degree of matrilineal genetic heterogeneity and weak population structuring of Armenians. Moreover, our phylogeographic analysis reveals common ancestries for some mtDNA lineages shared by West Asians, Transcaucasians, Europeans, Central Asians and Armenians. About third of the mtDNA subhaplogroups found in Armenian gene pool might be considered as Armenian-specific, as these are virtually absent elsewhere in Europe, West Asia and Transcaucasia. Coalescence ages of most of these lineages do not exceed 3.1 kya and coincide well with the population size growth started around 1.8-2.8 kya detectable only in the Bayesian Skyline Plots based on the Armenian-specific mtDNA haplotypes.


Assuntos
Genoma Mitocondrial , Armênia , Ásia Central , Ásia Ocidental , DNA Mitocondrial/química , Europa (Continente) , Variação Genética , Haplótipos , Humanos , Filogenia , Filogeografia
6.
Oncoimmunology ; 8(1): e1512329, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30546947

RESUMO

Multiple immunotherapeutics have been approved for cancer patients, however advanced solid tumors are frequently refractory to treatment. We evaluated the safety and immunogenicity of a vaccination approach with multimodal oncolytic potential in non-human primates (NHP) (Macaca fascicularis). Primates received a replication-deficient adenoviral prime, boosted by the oncolytic Maraba MG1 rhabdovirus. Both vectors expressed the human MAGE-A3. No severe adverse events were observed. Boosting with MG1-MAGEA3 induced an expansion of hMAGE-A3-specific CD4+ and CD8+ T-cells with the latter peaking at remarkable levels and persisting for several months. T-cells reacting against epitopes fully conserved between simian and human MAGE-A3 were identified. Humoral immunity was demonstrated by the detection of circulating MAGE-A3 antibodies. These preclinical data establish the capacity for the Ad:MG1 vaccination to engage multiple effector immune cell populations without causing significant toxicity in outbred NHPs. Clinical investigations utilizing this program for the treatment of MAGE-A3-positive solid malignancies are underway (NCT02285816, NCT02879760).

7.
Nat Commun ; 9(1): 3049, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30076299

RESUMO

Engineering T cells with chimeric antigen receptors (CARs) is an effective method for directing T cells to attack tumors, but may cause adverse side effects such as the potentially lethal cytokine release syndrome. Here the authors show that the T cell antigen coupler (TAC), a chimeric receptor that co-opts the endogenous TCR, induces more efficient anti-tumor responses and reduced toxicity when compared with past-generation CARs. TAC-engineered T cells induce robust and antigen-specific cytokine production and cytotoxicity in vitro, and strong anti-tumor activity in a variety of xenograft models including solid and liquid tumors. In a solid tumor model, TAC-T cells outperform CD28-based CAR-T cells with increased anti-tumor efficacy, reduced toxicity, and faster tumor infiltration. Intratumoral TAC-T cells are enriched for Ki-67+ CD8+ T cells, demonstrating local expansion. These results indicate that TAC-T cells may have a superior therapeutic index relative to CAR-T cells.


Assuntos
Receptores de Antígenos/imunologia , Receptores de Antígenos Quiméricos/imunologia , Proteínas Recombinantes/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Linfócitos T/imunologia , Transferência Adotiva , Animais , Antígenos CD28/imunologia , Linhagem Celular Tumoral , Citocinas/sangue , Citocinas/metabolismo , Citotoxicidade Imunológica , Feminino , Engenharia Genética , Células HEK293 , Humanos , Imunoterapia Adotiva/métodos , Lentivirus/genética , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos NOD , Engenharia de Proteínas , Receptor ErbB-2/imunologia , Receptores de Antígenos/genética , Receptores de Antígenos Quiméricos/genética , Anticorpos de Domínio Único , Especificidade do Receptor de Antígeno de Linfócitos T/genética , Linfócitos T Citotóxicos/imunologia , Visão Ocular , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Mol Genet Genomics ; 293(5): 1255-1263, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29948329

RESUMO

Complete mitochondrial genomics is an effective tool for studying the demographic history of human populations, but there is still a deficit of mitogenomic data in European populations. In this paper, we present results of study of variability of 80 complete mitochondrial genomes in two Hungarian populations from eastern part of Hungary (Szeged and Debrecen areas). The genetic diversity of Hungarian mitogenomes is remarkably high, reaching 99.9% in a combined sample. According to the analysis of molecular variance (AMOVA), European populations showed a low, but statistically significant level of between-population differentiation (Fst = 0.61%, p = 0), and two Hungarian populations demonstrate lack of between-population differences. Phylogeographic analysis allowed us to identify 71 different mtDNA sub-clades in Hungarians, sixteen of which are novel. Analysis of ancestry-informative mtDNA sub-clades revealed a complex genetic structure associated with the genetic impact of populations from different parts of Eurasia, though the contribution from European populations is the most pronounced. At least 8% of ancestry-informative haplotypes found in Hungarians demonstrate similarity with East and West Slavic populations (sub-clades H1c23a, H2a1c1, J2b1a6, T2b25a1, U4a2e, K1c1j, and I1a1c), while the influence of Siberian populations is not so noticeable (sub-clades A12a, C4a1a, and probably U4b1a4).


Assuntos
DNA Mitocondrial/genética , Etnicidade/genética , Variação Genética , Genética Populacional , Genoma Mitocondrial , Haplótipos , Humanos , Hungria , Filogeografia
9.
J Hum Genet ; 63(1): 71-81, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29215085

RESUMO

In this paper we present a results of first comprehensive study of the complete mitogenomes in the Buryats with regard to their belonging to the main regional (eastern and western Buryats); tribal (Khori, Ekhirid, Bulagad, and Khongodor), and ethno-territorial (Aginsk, Alar, Balagansk, Barguzin, Ida, Khorinsk, Kuda, Selenga, Verkholensk, Olkhon, Tunka, and Shenehen Buryats) groups. The analysis of molecular variation performed using regional, tribal, and ethno-territorial divisions of the Buryats showed lack of genetic differentiation at all levels. Nonetheless, the complete mitogenome analysis revealed a very high level of genetic diversity in the Buryats which is the highest among Siberian populations and comparable to that in populations of eastern and western Asia. The AMOVA and MDS analyses results imply to a strong genetic similarity between the Buryats and eastern Asian populations of Chinese and Japanese, suggesting their origin on the basis of common maternal ancestry components. Several new Buryat-specific branches of haplogroup G (G2a2a, G2a1i, G2a5a) display signals of dispersals dating to 2.6-6.6 kya with a possible origin in eastern Asia, thus testifying Bronze Age and Neolithic arrival of ancestral eastern Asian component to the South Siberia region.


Assuntos
Povo Asiático/etnologia , Povo Asiático/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Filogenia , Feminino , Humanos , Masculino , Sibéria/etnologia
10.
Curr Biol ; 27(13): 2023-2028.e7, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28669760

RESUMO

The South Caucasus, situated between the Black and Caspian Seas, geographically links Europe with the Near East and has served as a crossroad for human migrations for many millennia [1-7]. Despite a vast archaeological record showing distinct cultural turnovers, the demographic events that shaped the human populations of this region is not known [8, 9]. To shed light on the maternal genetic history of the region, we analyzed the complete mitochondrial genomes of 52 ancient skeletons from present-day Armenia and Artsakh spanning 7,800 years and combined this dataset with 206 mitochondrial genomes of modern Armenians. We also included previously published data of seven neighboring populations (n = 482). Coalescence-based analyses suggest that the population size in this region rapidly increased after the Last Glacial Maximum ca. 18 kya. We find that the lowest genetic distance in this dataset is between modern Armenians and the ancient individuals, as also reflected in both network analyses and discriminant analysis of principal components. We used approximate Bayesian computation to test five different demographic scenarios explaining the formation of the modern Armenian gene pool. Despite well documented cultural shifts in the South Caucasus across this time period, our results strongly favor a genetic continuity model in the maternal gene pool. This has implications for interpreting prehistoric migration dynamics and cultural shifts in this part of the world.


Assuntos
Pool Gênico , Variação Genética , Genoma Humano , Genoma Mitocondrial , Arqueologia , Armênia , Azerbaijão , Teorema de Bayes , DNA Antigo/análise , Migração Humana , Humanos
11.
J Hum Genet ; 61(6): 491-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26911356

RESUMO

Y chromosome microsatellite (Y-STR) diversity has been studied in different Mongolic-speaking populations from South Siberia, Mongolia, North-East China and East Europe. The results obtained indicate that the Mongolic-speaking populations clustered into two groups, with one group including populations from eastern part of South Siberia and Central Asia (the Buryats, Barghuts and Khamnigans) and the other group including populations from western part of Central Asia and East Europe (the Mongols and Kalmyks). High frequency of haplogroup C3-M407 (>50%) is present in the Buryats, Barghuts and Khamnigans, whereas in the Mongols and Kalmyks its frequency is much lower. In addition, two allelic combinations in DYS385a,b loci of C3-M407 haplotypes have been observed: the combination 11,18 (as well as 11,17 and 11,19) is frequent in different Mongolic-speaking populations, but the 11,11 branch is present mainly in the Kalmyks and Mongols. Results of locus-specific sequencing suggest that the action of gene conversion is a more likely explanation for origin of homoallelic 11,11 combination. Moreover, analysis of median networks of Y-STR haplotypes demonstrates that at least two gene conversion events can be revealed-one of them has probably occurred among the Mongols, and the other event occurred in the Barghuts. These two events give an average gene conversion rate range of 0.24-7.1 × 10(-3) per generation.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y , Conversão Gênica , Variação Genética , Genética Populacional , Haplótipos , Repetições de Microssatélites , Alelos , China , Análise por Conglomerados , Etnicidade/genética , Evolução Molecular , Frequência do Gene , Loci Gênicos , Humanos , Masculino , Mutação , Federação Russa
12.
J Immunother Cancer ; 3: 55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26673402

RESUMO

BACKGROUND: Adoptive cell transfer of tumor-specific T lymphocytes (T cells) is proving to be an effective strategy for treating established tumors in cancer patients. One method of generating these cells is accomplished through engineering bulk T cell populations to express chimeric antigen receptors (CARs), which are specific for tumor antigens. Traditionally, these CARs are targeted against tumor antigens using single-chain antibodies (scFv). Here we describe the use of a designed ankyrin repeat protein (DARPin) as the tumor-antigen targeting domain. METHODS: We prepared second generation anti-HER2 CARs that were targeted to the tumor antigen by either a DARPin or scFv. The CARs were engineered into human and murine T cells. We then compared the ability of CARs to trigger cytokine production, degranulation and cytotoxicity. RESULTS: The DARPin CARs displayed reduced surface expression relative to scFv CARs in murine cells but both CARs were expressed equally well on human T cells, suggesting that there may be a processing issue with the murine variants. In both the murine and human systems, the DARPin CARs were found to be highly functional, triggering cytokine and cytotoxic responses that were similar to those triggered by the scFv CARs. CONCLUSIONS: These findings demonstrate the utility of DARPins as CAR-targeting agents and open up an avenue for the generation of CARs with novel antigen binding attributes.

13.
Mol Ther ; 23(10): 1600-10, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122933

RESUMO

Ligands for the NKG2D receptor are overexpressed on tumors, making them interesting immunotherapy targets. To assess the tumoricidal properties of T cells directed to attack NKG2D ligands, we engineered murine T cells with two distinct NKG2D-based chimeric antigen receptors (CARs): (i) a fusion between the NKG2D receptor and the CD3ζ chain and (ii) a conventional second-generation CAR, where the extracellular domain of NKG2D was fused to CD28 and CD3ζ. To enhance the CAR surface expression, we also engineered T cells to coexpress DAP10. In vitro functionality and surface expression levels of all three CARs was greater in BALB/c T cells than C57BL/6 T cells, indicating strain-specific differences. Upon adoptive transfer of NKG2D-CAR-T cells into syngeneic animals, we observed significant clinical toxicity resulting in morbidity and mortality. The severity of these toxicities varied between the CAR configurations and paralleled their in vitro NKG2D surface expression. BALB/c mice were more sensitive to these toxicities than C57BL/6 mice, consistent with the higher in vitro functionality of BALB/c T cells. Treatment with cyclophosphamide prior to adoptive transfer exacerbated the toxicity. We conclude that while NKG2D ligands may be useful targets for immunotherapy, the pursuit of NKG2D-based CAR-T cell therapies should be undertaken with caution.


Assuntos
Citotoxicidade Imunológica , Proteínas Recombinantes de Fusão , Transferência Adotiva , Animais , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Ciclofosfamida/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Vetores Genéticos/genética , Imunoterapia Adotiva , Ligantes , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Pneumonia/imunologia , Pneumonia/metabolismo , Pneumonia/patologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Retroviridae/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Condicionamento Pré-Transplante
14.
BMC Evol Biol ; 14: 217, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25301575

RESUMO

BACKGROUND: Although the genetic heritage of aboriginal Siberians is mostly of eastern Asian ancestry, a substantial western Eurasian component is observed in the majority of northern Asian populations. Traces of at least two migrations into southern Siberia, one from eastern Europe and the other from western Asia/the Caucasus have been detected previously in mitochondrial gene pools of modern Siberians. RESULTS: We report here 166 new complete mitochondrial DNA (mtDNA) sequences that allow us to expand and re-analyze the available data sets of western Eurasian lineages found in northern Asian populations, define the phylogenetic status of Siberian-specific subclades and search for links between mtDNA haplotypes/subclades and events of human migrations. From a survey of 158 western Eurasian mtDNA genomes found in Siberia we estimate that nearly 40% of them most likely have western Asian and another 29% European ancestry. It is striking that 65 of northern Asian mitogenomes, i.e. ~41%, fall into 19 branches and subclades which can be considered as Siberian-specific being found so far only in Siberian populations. From the coalescence analysis it is evident that the sequence divergence of Siberian-specific subclades was relatively small, corresponding to only 0.6-9.5 kya (using the complete mtDNA rate) and 1-6 kya (coding region rate). CONCLUSIONS: The phylogeographic analysis implies that the western Eurasian founders, giving rise to Siberian specific subclades, may trace their ancestry only to the early and mid-Holocene, though some of genetic lineages may trace their ancestry back to the end of Last Glacial Maximum (LGM). We have not found the modern northern Asians to have western Eurasian genetic components of sufficient antiquity to indicate traces of pre-LGM expansions.


Assuntos
DNA Mitocondrial/genética , Pool Gênico , Genética Populacional , Povo Asiático/genética , Feminino , Genética Médica , Humanos , Dados de Sequência Molecular , Filogenia , Filogeografia , Sibéria , População Branca/genética
15.
Gene ; 550(1): 56-67, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25110108

RESUMO

We assessed phylogeny of sable (Martes zibellina, Linnaeus, 1758) by sequence analysis of nearly complete, new mitochondrial genomes in 36 specimens from different localities in northern Eurasia (Primorye, Khabarovsk and Krasnoyarsk regions, the Kamchatka Peninsula, the Kuril Islands and the Urals). Phylogenetic analysis of mtDNA sequences demonstrates that two clades, A and BC, radiated about 200-300 thousandyears ago (kya) according to results of Bayesian molecular clock and RelTime analyses of different mitogenome alignments (nearly complete mtDNA sequences, protein-coding region, and synonymous sites), while the age estimates of clades A, B and C fall within the Late Pleistocene (~50-140 kya). Bayesian skyline plots (BSPs) of sable population size change based on analysis of nearly complete mtDNAs show an expansion around 40 kya in the warm Karganian time, without a decline of population size around the Last Glacial Maximum (21 kya). The BSPs based on synonymous clock rate indicate that M. zibellina experienced demographic expansions later, approximately 22 kya. The A2a clade that colonized Kamchatka ~23-50 kya (depending on the mutation rate used) survived the last glaciation there as demonstrated by the BSP analysis. In addition, we have found evidence of positive selection acting at ND4 and cytochrome b genes, thereby suggesting adaptive evolution of the A2a clade in Kamchatka.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Mustelidae/genética , Filogenia , Animais , Ásia , Teorema de Bayes , Citocromos b/genética , DNA Mitocondrial/química , DNA Mitocondrial/classificação , Europa (Continente) , Evolução Molecular , Variação Genética , Genética Populacional , Geografia , Dados de Sequência Molecular , NADH Desidrogenase/genética , Seleção Genética , Análise de Sequência de DNA , Fatores de Tempo
16.
Parasitol Int ; 63(1): 100-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24064255

RESUMO

Phylogenetic and statistical analyses of DNA sequences of two genes, cytochrome oxidase subunit 1 (cox 1) of the mitochondrial DNA and 18S subunit of the nuclear ribosomal RNA (18S rRNA), was used to characterize Neoechinorhynchus species from fishes collected in different localities of North-East Asia. It has been found that four species can be clearly recognized using molecular markers-Neoechinorhynchus tumidus, Neoechinorhynchus beringianus, Neoechinorhynchus simansularis and Neoechinorhynchus salmonis. 18S sequences ascribed to Neoechinorhynchus crassus specimens from North-East Asia were identical to those of N. tumidus, but differed substantially from North American N. crassus. We renamed North-East Asian N. crassus specimens to N. sp., although the possibility that they represent a subspecies of N. tumidus cannot be excluded, taking into account a relatively small distance between cox 1 sequences of North-East Asian specimens of N. crassus and N. tumidus. Maximum likelihood, maximum parsimony and Bayesian inference analyses were performed for phylogeny reconstruction. All the phylogenetic trees showed that North-East Asian species of Neoechinorhynchus analyzed in this study represent independent clades, with the only exception of N. tumidus and N. sp. for 18S data. Phylogenetic analysis has shown that the majority of species sampled (N. tumidus+N. sp., N. simansularis and N. beringianus) are probably very closely related, while N. salmonis occupies separate position in the trees, possibly indicating a North American origin of this species.


Assuntos
Acantocéfalos/genética , Variação Genética , Filogenia , Animais , Ásia/epidemiologia , DNA/genética , Demografia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peixes , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Especificidade da Espécie
17.
PLoS One ; 8(11): e80673, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244704

RESUMO

Due to its pivotal geographical location and proximity to transcontinental migratory routes, Iran has played a key role in subsequent migrations, both prehistoric and historic, between Africa, Asia and Europe. To shed light on the genetic structure of the Iranian population as well as on the expansion patterns and population movements which affected this region, the complete mitochondrial genomes of 352 Iranians were obtained. All Iranian populations studied here exhibit similarly high diversity values comparable to the other groups from the Caucasus, Anatolia and Europe. The results of AMOVA and MDS analyses did not associate any regional and/or linguistic group of populations in the Anatolia/Caucasus and Iran region pointing to close genetic positions of Persians and Qashqais to each other and to Armenians, and Azeris from Iran to Georgians. By reconstructing the complete mtDNA phylogeny of haplogroups R2, N3, U1, U3, U5a1g, U7, H13, HV2, HV12, M5a and C5c we have found a previously unexplored genetic connection between the studied Iranian populations and the Arabian Peninsula, India, Near East and Europe, likely the result of both ancient and recent gene flow. Our results for Persians and Qashqais point to a continuous increase of the population sizes from ∼24 kya to the present, although the phase between 14-24 kya is thought to be hyperarid according to the Gulf Oasis model. Since this would have affected hunter-gatherer ranges and mobility patterns and forced them to increasingly rely on coastal resources, this transition can explain the human expansion across the Persian Gulf region.


Assuntos
DNA Mitocondrial/genética , Fluxo Gênico/genética , Genética Populacional , Haplótipos , Humanos , Irã (Geográfico) , Filogenia , População Branca
18.
J Hum Genet ; 58(12): 804-11, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24132124

RESUMO

The Mongolic-speaking Kalmyks currently inhabiting the steppes of the Volga region have Central Asian ancestry and are organized into the tribal groups. The genetic relationships among these tribes and their origin have remained obscure. We analyzed 17 short tandem repeat and 44 binary polymorphisms of Y-chromosome in 426 individuals mainly from three major tribes of the Kalmyks (the Torguuds, Dörwöds and Khoshuuds). Among these tribes, the Dörwöds and Torguuds, as well as the Kalmyks collectively as an ethnic group, showed relatively close genetic affinities to each other and to the Mongols and Altaian Kazakhs, whereas the Khoshuuds were clearly separated from all of them, gathering with the Manchu, Tibetans or Evenks (depending on the algorithm used to calculate genetic distances). The genetic results also indicate that paternal gene flow from East Europeans to the Kalmyks is very little, despite their cohabitation in the North Caspian Steppe during the last 380 years. The occurrence of unique cluster of N1c-Tat haplotypes in the Khoshuuds, which dates to about 340 years and is likely to have East European ancestry, is considered as a result of interethnic contacts occurred soon after the appearance of the Kalmyk tribes in the Volga-Ural region.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y/genética , Etnicidade/genética , Polimorfismo Genético/genética , População Branca/genética , Fluxo Gênico/genética , Frequência do Gene/genética , Genética Populacional , Haplótipos , Humanos , Masculino , Repetições de Microssatélites/genética
19.
Mol Phylogenet Evol ; 67(2): 348-57, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23415986

RESUMO

We assessed phylogeny of the Siberian salamander (Salamandrella keyserlingii, Dybowski, 1870), the most northern ectothermic, terrestrial vertebrate in Eurasia, by sequence analysis of complete mitochondrial genomes in 26 specimens from different localities (China, Khabarovsk region, Sakhalin, Yakutia, Magadan region, Chukotka, Kamchatka, Ural, European part of Russia). In addition, a complete mitochondrial genome of the Schrenck salamander, Salamandrella schrenckii, was determined for the first time. Bayesian phylogenetic analysis of the entire mtDNA genomes of S. keyserlingii demonstrates that two haplotype clades, AB and C, radiated about 1.4 million years ago (Mya). Bayesian skyline plots of population size change through time show an expansion around 250 thousand years ago (kya) and then a decline around the Last Glacial Maximum (25 kya) with subsequent restoration of population size. Climatic changes during the Quaternary period have dramatically affected the population genetic structure of the Siberian salamanders. In addition, complete mtDNA sequence analysis allowed us to recognize that the vast area of Northern Eurasia was colonized only by the Siberian salamander clade C1b during the last 150 kya. Meanwhile, we were unable to find evidence of molecular adaptation in this clade by analyzing the whole mitochondrial genomes of the Siberian salamanders.


Assuntos
Genoma Mitocondrial , Filogenia , Urodelos , Animais , Genética Populacional , Haplótipos , Federação Russa , Análise de Sequência de DNA , Sibéria , Urodelos/classificação , Urodelos/genética
20.
J Hum Genet ; 57(10): 685-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22810113

RESUMO

As there are ambiguities in classification of the Y-chromosome haplogroup C3c, relatively frequent in populations of Northern Asia, we analyzed all three haplogroup-defining markers M48, M77 and M86 in C3-M217-individuals from Siberia, Eastern Asia and Eastern Europe. We have found that haplogroup C3c is characterized by the derived state at M48, whereas mutations at both M77 and M86 define subhaplogroup C3c1. The branch defined by M48 alone would belong to subhaplogroup C3c*, characteristic for some populations of Central and Eastern Siberia, such as Koryaks, Evens, Evenks and Yukaghirs. Subhaplogroup C3c* individuals could be considered as remnants of the Neolithic population of Siberia, based on the age of C3c*-short tandem repeat variation amounting to 4.5 ± 2.4 thousand years.


Assuntos
Cromossomos Humanos Y/genética , Etnicidade/genética , Genética Populacional/métodos , Haplótipos , Europa Oriental , Ásia Oriental , Marcadores Genéticos , Humanos , Masculino , Repetições Minissatélites , Mutação , Filogenia , Polimorfismo de Nucleotídeo Único , Sibéria
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