The counteracting effects of demography on functional genomic variation: the Roma paradigm

Demographic history plays a major role in shaping the distribution of genomic variation. Yet the interaction between different demographic forces and their effects in the genomes is not fully resolved in human populations. Here, we focus on the Roma population, the largest transnational ethnic minor...

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Detalles Bibliográficos
Autores: Font-Porterias, Neus, Caro Consuegra, Rocio, Lucas Sánchez, Marcel, López, Marie, Giménez, Aaron, Carballo Mesa, Annabel, Bosch Fusté, Elena, Calafell i Majó, Francesc, Quintana Murci, Lluis, Comas, David, 1969-
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/48317
Acceso en línea:http://hdl.handle.net/10230/48317
http://dx.doi.org/10.1093/molbev/msab070
Access Level:acceso abierto
Palabra clave:Roma
Adaptation
Admixture
Demography
Exomes
Mutational load
Descripción
Sumario:Demographic history plays a major role in shaping the distribution of genomic variation. Yet the interaction between different demographic forces and their effects in the genomes is not fully resolved in human populations. Here, we focus on the Roma population, the largest transnational ethnic minority in Europe. They have a South Asian origin and their demographic history is characterized by recent dispersals, multiple founder events, and extensive gene flow from non-Roma groups. Through the analyses of new high-coverage whole exome sequences and genome-wide array data for 89 Iberian Roma individuals together with forward simulations, we show that founder effects have reduced their genetic diversity and proportion of rare variants, gene flow has counteracted the increase in mutational load, runs of homozygosity show ancestry-specific patterns of accumulation of deleterious homozygotes, and selection signals primarily derive from preadmixture adaptation in the Roma population sources. The present study shows how two demographic forces, bottlenecks and admixture, act in opposite directions and have long-term balancing effects on the Roma genomes. Understanding how demography and gene flow shape the genome of an admixed population provides an opportunity to elucidate how genomic variation is modeled in human populations.