Genetic Variation and Signatures of Natural Selection in Diverse Africans
Ontology highlight
ABSTRACT: Our study identified candidate regions of genome involved in adaptation and identified regions associated with selected phenotypes.
PROVIDER: phs000449.v2.p1 | EGA |
REPOSITORIES: EGA
Publications
Genetic adaptation to high altitude in the Ethiopian highlands.
Scheinfeldt Laura B LB Soi Sameer S Thompson Simon S Ranciaro Alessia A Woldemeskel Dawit D Beggs William W Lambert Charla C Jarvis Joseph P JP Abate Dawit D Belay Gurja G Tishkoff Sarah A SA
Genome biology 20120120 1
<h4>Background</h4>Genomic analysis of high-altitude populations residing in the Andes and Tibet has revealed several candidate loci for involvement in high-altitude adaptation, a subset of which have also been shown to be associated with hemoglobin levels, including EPAS1, EGLN1, and PPARA, which play a role in the HIF-1 pathway. Here, we have extended this work to high- and low-altitude populations living in Ethiopia, for which we have measured hemoglobin levels. We genotyped the Illumina 1M S ...[more]
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Project description:<p>Our study identified candidate regions of genome involved in adaptation and identified regions associated with selected phenotypes.</p>
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Project description:Genetic variation and signatures of natural selection in diverse Africans
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Project description:In Arabidopsis thaliana a high rate of spontaneous epigenetic variation can occur in the DNA methylome in the absence of genetic variation and selection. It has been of great interest, whether natural epigenetic variation is subject to selection and contributes to fitness and adaptation in selective environments. We compared the variation in selected phenotypic traits, genome-wide cytosine DNA methylation and gene expression in two Arabidopsis recombinant inbred lines, which had undergone five generations of selection in experimental landscapes relative to their genetically identical ancestors. Selected populations exerted significant differences in flowering time and the number of branches and fruits, differences that were maintained over two to three generations in the absence of selection. We identified 4,629 and 5,158 differentially methylated cytosines which were overrepresented in genes that regulate flowering time, epigenetic processes, development and morphogenesis. Differentially methylated genes were enriched in differentially expressed genes. Thus, epigenetic variation is subject to selection and may play an important role in the adaptive response of populations in rapidly changing natural environments.
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