Strong signatures of positive selection at newly arising genetic variants are well documented in humans1,2,3,4,5,6,7,8, but this form of selection may not be widespread in recent human evolution9. Because many human traits are highly polygenic and partly determined by common, ancient genetic variation, an alternative model for rapid genetic adaptation has been proposed: weak selection acting on many pre-existing (standing) genetic variants, or polygenic adaptation10,11,12. By studying height, a classic polygenic trait, we demonstrate the first human signature of widespread selection on standing variation. We show that frequencies of alleles associated with increased height, both at known loci and genome wide, are systematically elevated in Northern Europeans compared with Southern Europeans (P < 4.3 × 10−4). This pattern mirrors intra-European height differences and is not confounded by ancestry or other ascertainment biases. The systematic frequency differences are consistent with the presence of widespread weak selection (selection coefficients ∼10−3–10−5 per allele) rather than genetic drift alone (P < 10−15).
The authors would like to thank E.L. Altmaier, K.E. Samocha, S.R. Grossman, G. Coop, other attendees of the Biology of Genomes 2011 conference, B.F. Voight, M. McCarthy, P. Visscher and other members of the Reich and Hirschhorn labs for their discussions and helpful comments. We gratefully thank the GIANT consortium and particularly the members of the height working group for making unpublished association data available. We thank the MIGen consortium for making allele frequency data available. This research was conducted using data and resources from the FHS of the National Heart, Lung, and Blood Institute of the US National Institutes of Health and Boston University School of Medicine based on analyses by FHS investigators participating in the SNP Health Association Resource project. This work was supported by the National Heart, Lung and Blood Institute's FHS (contract no. N01-HC-25195) and its contract with Affymetrix, Inc., for genotyping services (contract no. N02-HL-6-4278). A portion of this research used the Linux Cluster for Genetic Analysis (LinGA-II) funded by the Robert Dawson Evans Endowment of the Department of Medicine at Boston University School of Medicine and Boston Medical Center. This work was also supported by a graduate research fellowship from the National Science Foundation (to C.W.K.C.), the March of Dimes (6-FY09-507 to J.N.H.) and the National Institute of Diabetes and Digestive and Kidney Diseases (1R01DK075787 to J.N.H.).
Supplementary Tables 1–13, Supplementary Figures 1–10 and Supplementary Note