title: Classic selective sweeps were rare in recent human evolution.
abstract: Efforts to identify the genetic basis of human adaptations from polymorphism data have sought footprints of "classic selective sweeps" (in which a beneficial mutation arises and rapidly fixes in the population).Yet it remains unknown whether this form of natural selection was common in our evolution. We examined the evidence for classic sweeps in resequencing data from 179 human genomes. As expected under a recurrent-sweep model, we found that diversity levels decrease near exons and conserved noncoding regions. In contrast to expectation, however, the trough in diversity around human-specific amino acid substitutions is no more pronounced than around synonymous substitutions. Moreover, relative to the genome background, amino acid and putative regulatory sites are not significantly enriched in alleles that are highly differentiated between populations. These findings indicate that classic sweeps were not a dominant mode of human adaptation over the past ~250,000 years.
authors.affiliation: Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Ryan D
authors.initials: RD
authors.lastname: Hernandez
authors.forename: Joanna L
authors.initials: JL
authors.lastname: Kelley
authors.forename: Eyal
authors.initials: E
authors.lastname: Elyashiv
authors.forename: S Cord
authors.initials: SC
authors.lastname: Melton
authors.forename: Adam
authors.initials: A
authors.lastname: Auton
authors.forename: Gilean
authors.initials: G
authors.lastname: McVean
authors.forename: Guy
authors.initials: G
authors.lastname: Sella
authors.forename: Molly
authors.initials: M
authors.lastname: Przeworski
mesh_terms: D000220:Adaptation, Biological; D019943:Amino Acid Substitution; D005075:Biological Evolution; D041321:Chromosomes, Human, X / Q000235:genetics; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005091:Exons; D005787:Gene Frequency; D014644:Genetic Variation; D015894:Genome, Human; D006239:Haplotypes; D006801:Humans; D008957:Models, Genetic; D058977:Molecular Sequence Annotation; D009154:Mutation; D020641:Polymorphism, Single Nucleotide; D011995:Recombination, Genetic; D012641:Selection, Genetic; D020506:Untranslated Regions
chemical_list: D020506:Untranslated Regions