Signals of recent positive selection in a worldwide sample of human populations

Abstract

Genome-wide scans for recent positive selection in humans have yielded insight into the mechanisms underlying the extensive phenotypic diversity in our species, but have focused on a limited number of populations. Here, we present an analysis of recent selection in a global sample of 53 populations, using genotype data from the Human Genome Diversity-CEPH Panel. We refine the geographic distributions of known selective sweeps, and find extensive overlap between these distributions for populations in the same continental region but limited overlap between populations outside these groupings. We present several examples of previously unrecognized candidate targets of selection, including signals at a number of genes in the NRG-ERBB4 developmental pathway in non-African populations. Analysis of recently identified genes involved in complex diseases suggests that there has been selection on loci involved in susceptibility to type II diabetes. Finally, we search for local adaptation between geographically close populations, and highlight several examples.

Genomic landscape of positive natural selection in Northern European populations

“…20 We sought to characterize the applicability of the tests for genome-wide data sets by analyzing the joint effects of SNP density and sample size. We performed coalescent simulations using the SelSim software, 28 simulating genomic segments with a neutral model and with natural selection (see Supplementary Methods for details of the simulations and subsequent analyses).…”

“…These data have also provided a powerful tool for analyzing population differentiation and structure, [14][15][16][17][18] but to date, only a few studies have used similar data sets for analyzing traces of positive natural selection. 5,10,19,20 In this study, we used a genome-wide data set from Eastern and Western Finland, Sweden, Northern Germany, and Great Britain, and a combination of three statistical methods to search for loci that have been affected by recent natural selection.…”

Local Selection Across a Latitudinal Gradient Shapes Nucleotide Diversity in Balsam Poplar, Populus balsamifera L

“…However, molecular population genetic analyses of selection often focus on detecting selective sweeps driven by positive directional selection in a species-wide sample (Nielsen 2005). Only recently have studies started to scan patterns of gene nucleotide diversity for signatures of selection below the species level, particularly among human regional subpopulations (Tang et al 2007;Nielsen et al 2009;Pickrell et al 2009;Chen et al 2010). …”

Immunité innée et maladies chez l’homme

“…Une comparaison du génome humain avec celui du chimpanzé a ainsi montré que certains des gènes présentant des évi-dences moléculaires d'une évolution accélérée depuis la divergence entre ces deux espèces étaient enrichis en fonctions immunitaires [24]. Les études de plusieurs populations humaines ont aussi révélé que de nombreux gènes impliqués dans les réponses immunes font partie des régions génomiques ayant le plus participé à l'adaptation récente de ces groupes d'individus à leurs environnements respectifs [1, [25][26][27]. De plus, la variabilité génétique touchant des gènes de l'immunité peut être corrélée à la richesse pathogénique de l'environnement.…”