RT Journal Article SR Electronic T1 Population-specific causal disease effect sizes in functionally important regions impacted by selection JF bioRxiv FD Cold Spring Harbor Laboratory SP 803452 DO 10.1101/803452 A1 Huwenbo Shi A1 Steven Gazal A1 Masahiro Kanai A1 Evan M. Koch A1 Armin P. Schoech A1 Samuel S. Kim A1 Yang Luo A1 Tiffany Amariuta A1 Yukinori Okada A1 Soumya Raychaudhuri A1 Shamil R. Sunyaev A1 Alkes L. Price YR 2019 UL http://biorxiv.org/content/early/2019/10/30/803452.abstract AB Many diseases and complex traits exhibit population-specific causal effect sizes with trans-ethnic genetic correlations significantly less than 1, limiting trans-ethnic polygenic risk prediction. We developed a new method, S-LDXR, for stratifying squared trans-ethnic genetic correlation across genomic annotations, and applied S-LDXR to genome-wide association summary statistics for 30 diseases and complex traits in East Asians (EAS) and Europeans (EUR) (average NEAS=93K, NEUR=274K) with an average trans-ethnic genetic correlation of 0.83 (s.e. 0.01). We determined that squared trans-ethnic genetic correlation was 0.81× (s.e. 0.01) smaller than the genome-wide average at SNPs in the top quintile of background selection statistic, implying more population-specific causal effect sizes. Accordingly, causal effect sizes were more population-specific in functionally important regions, including coding, conserved, and regulatory regions. In analyses of regions surrounding specifically expressed genes, causal effect sizes were most population-specific for skin and immune genes and least population-specific for brain genes. Our results could potentially be explained by stronger gene-environment interaction at loci impacted by selection, particularly positive selection.