A Map of Recent Positive Selection in the Human Genome

Department of Human Genetics, University of Chicago, Chicago, Illinois, USA.
PLoS Biology (Impact Factor: 11.77). 04/2006; 4(3):e72. DOI: 10.1371/journal.pbio.0040072
Source: PubMed

ABSTRACT The identification of signals of very recent positive selection provides information about the adaptation of modern humans to local conditions. We report here on a genome-wide scan for signals of very recent positive selection in favor of variants that have not yet reached fixation. We describe a new analytical method for scanning single nucleotide polymorphism (SNP) data for signals of recent selection, and apply this to data from the International HapMap Project. In all three continental groups we find widespread signals of recent positive selection. Most signals are region-specific, though a significant excess are shared across groups. Contrary to some earlier low resolution studies that suggested a paucity of recent selection in sub-Saharan Africans, we find that by some measures our strongest signals of selection are from the Yoruba population. Finally, since these signals indicate the existence of genetic variants that have substantially different fitnesses, they must indicate loci that are the source of significant phenotypic variation. Though the relevant phenotypes are generally not known, such loci should be of particular interest in mapping studies of complex traits. For this purpose we have developed a set of SNPs that can be used to tag the strongest approximately 250 signals of recent selection in each population.

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Available from: Xiaoquan Wen, Sep 01, 2015
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    • "e four regions of interest . Candidate regions of positive selec - tion were identified as containing any SNP with an iHS score of |iHS| > 2 , as this corresponds to the top ~5% of all scores . The iHS value at a SNP " measures the strength of evidence for selection acting at or near that SNP " however does not provide a formal significance test ( Voight et al . 2006 ) ."
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    PLoS ONE 08/2015; 10(8):e0134393. DOI:10.1371/journal.pone.0134393 · 3.23 Impact Factor
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    • "Based on the assumption that adaptive mutations are likely to be dominant, positive selection should drive these mutations to high population frequency removing genetic variation at linked sites and thus leaving characteristic molecular signatures of complete selective sweeps. Until recently most genomic scans for positive selection were focused on identifying signatures of complete selective sweeps (Sabeti et al. 2002; Glinka et al. 2003; Voight et al. 2006). However, it has been recently shown that a substantial proportion of adaptive mutations may display heterozygote advantage (Sellis et al. 2011). "
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    Genome Biology and Evolution 04/2015; 7(5). DOI:10.1093/gbe/evv071 · 4.53 Impact Factor
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    • "Second is assessing the deleterious, beneficial, or neutral effects for mutations, which is unknown for the vast majority of human SNPs. The unexpectedly young age has been deduced only for several hundred mutations located in about 50 different loci that are associated with recent strong positive selection in the human genome [15] [16] [19]. Among the 22 strongest candidate loci for positive selection in humans presented by Sabeti et al. [16] in Table 1, the authors "
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