Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Curr Biol ; 33(1): 41-57.e15, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36493775

RESUMO

We present a spatiotemporal picture of human genetic diversity in Anatolia, Iran, Levant, South Caucasus, and the Aegean, a broad region that experienced the earliest Neolithic transition and the emergence of complex hierarchical societies. Combining 35 new ancient shotgun genomes with 382 ancient and 23 present-day published genomes, we found that genetic diversity within each region steadily increased through the Holocene. We further observed that the inferred sources of gene flow shifted in time. In the first half of the Holocene, Southwest Asian and the East Mediterranean populations homogenized among themselves. Starting with the Bronze Age, however, regional populations diverged from each other, most likely driven by gene flow from external sources, which we term "the expanding mobility model." Interestingly, this increase in inter-regional divergence can be captured by outgroup-f3-based genetic distances, but not by the commonly used FST statistic, due to the sensitivity of FST, but not outgroup-f3, to within-population diversity. Finally, we report a temporal trend of increasing male bias in admixture events through the Holocene.


Assuntos
Genoma Humano , Grupos Raciais , Humanos , Masculino , História Antiga , Irã (Geográfico) , Fluxo Gênico , Migração Humana , Genética Populacional
2.
Commun Biol ; 4(1): 1279, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34773064

RESUMO

Sheep were among the first domesticated animals, but their demographic history is little understood. Here we analyzed nuclear polymorphism and mitochondrial data (mtDNA) from ancient central and west Anatolian sheep dating from Epipaleolithic to late Neolithic, comparatively with modern-day breeds and central Asian Neolithic/Bronze Age sheep (OBI). Analyzing ancient nuclear data, we found that Anatolian Neolithic sheep (ANS) are genetically closest to present-day European breeds relative to Asian breeds, a conclusion supported by mtDNA haplogroup frequencies. In contrast, OBI showed higher genetic affinity to present-day Asian breeds. These results suggest that the east-west genetic structure observed in present-day breeds had already emerged by 6000 BCE, hinting at multiple sheep domestication episodes or early wild introgression in southwest Asia. Furthermore, we found that ANS are genetically distinct from all modern breeds. Our results suggest that European and Anatolian domestic sheep gene pools have been strongly remolded since the Neolithic.


Assuntos
DNA Antigo/análise , DNA Mitocondrial/análise , Domesticação , Polimorfismo Genético , Carneiro Doméstico/genética , Animais , Arqueologia , Núcleo Celular , Demografia , Turquia
3.
Science ; 361(6397): 85-88, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29976826

RESUMO

Current genetic data are equivocal as to whether goat domestication occurred multiple times or was a singular process. We generated genomic data from 83 ancient goats (51 with genome-wide coverage) from Paleolithic to Medieval contexts throughout the Near East. Our findings demonstrate that multiple divergent ancient wild goat sources were domesticated in a dispersed process that resulted in genetically and geographically distinct Neolithic goat populations, echoing contemporaneous human divergence across the region. These early goat populations contributed differently to modern goats in Asia, Africa, and Europe. We also detect early selection for pigmentation, stature, reproduction, milking, and response to dietary change, providing 8000-year-old evidence for human agency in molding genome variation within a partner species.


Assuntos
Domesticação , Cabras/genética , Mosaicismo , África , Animais , Animais Domésticos/classificação , Animais Domésticos/genética , Ásia , DNA Antigo , DNA Mitocondrial/genética , Europa (Continente) , Folistatina/genética , Variação Genética , Genoma , Cabras/classificação , Filogenia
4.
Acta Biomater ; 11: 151-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25242648

RESUMO

We report here a novel method for the synthesis of a pH-responsive composite using visible light. Formation of the pH-responsive layer is based on poly(methacrylic acid-g-ethylene glycol) as the macromer, eosin Y as the photoinitiator and triethanolamine as the co-initiator. The hydrogel was functionalized with hydrophobic domains through incorporation of crosslinked styrene-butadiene-styrene (SBS) copolymer into the pH-responsive prepolymer. Swelling ratios were decreased with the addition of SBS, and resulted in high hydrogel crosslink density. The composite allowed for controlled release of an anticonvulsant model drug, pregabalin, under neutral pH condition and the release was analyzed to describe the mode of transport through the network. In vitro human fibroblast survival assay and in vivo rabbit implantation experiments demonstrated that this hybrid network is not toxic and has desirable biocompatibility properties. This is the first report about the synthesis of a pH-responsive network incorporating crosslinked SBS synthesized under visible light. The approach for multifunctional membranes could allow the incorporation of molecules with specific functionalities so that sequential molecule delivery in response to specific stimuli could be achieved.


Assuntos
Anticonvulsivantes , Hidrogéis , Luz , Ácido gama-Aminobutírico/análogos & derivados , Animais , Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Sobrevivência Celular , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Avaliação Pré-Clínica de Medicamentos , Implantes de Medicamento , Feminino , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Pregabalina , Coelhos , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/farmacologia
5.
Mol Biol Evol ; 30(4): 824-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23180578

RESUMO

Zooarcheological evidence suggests that pigs were domesticated in Southwest Asia ~8,500 BC. They then spread across the Middle and Near East and westward into Europe alongside early agriculturalists. European pigs were either domesticated independently or more likely appeared so as a result of admixture between introduced pigs and European wild boar. As a result, European wild boar mtDNA lineages replaced Near Eastern/Anatolian mtDNA signatures in Europe and subsequently replaced indigenous domestic pig lineages in Anatolia. The specific details of these processes, however, remain unknown. To address questions related to early pig domestication, dispersal, and turnover in the Near East, we analyzed ancient mitochondrial DNA and dental geometric morphometric variation in 393 ancient pig specimens representing 48 archeological sites (from the Pre-Pottery Neolithic to the Medieval period) from Armenia, Cyprus, Georgia, Iran, Syria, and Turkey. Our results reveal the first genetic signatures of early domestic pigs in the Near Eastern Neolithic core zone. We also demonstrate that these early pigs differed genetically from those in western Anatolia that were introduced to Europe during the Neolithic expansion. In addition, we present a significantly more refined chronology for the introduction of European domestic pigs into Asia Minor that took place during the Bronze Age, at least 900 years earlier than previously detected. By the 5th century AD, European signatures completely replaced the endemic lineages possibly coinciding with the widespread demographic and societal changes that occurred during the Anatolian Bronze and Iron Ages.


Assuntos
DNA Mitocondrial/genética , Dente Molar/anatomia & histologia , Sus scrofa/genética , Distribuição Animal , Animais , Animais Domésticos/genética , Ásia , Europa (Continente) , Humanos , Filogeografia , Análise de Sequência de DNA , Suínos/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...