Stringent quality control was applied to each cohort following standard procedures for GWAS, including filters for call rate, Hardy-Weinberg equilibrium, and heterozygosity rates (Supplementary Information). Each cohort was then phased and imputed using the 1000 Genomes Project phase 3 (1KGP3)34,113 imputation reference panel using SHAPEIT114 and IMPUTE2115, respectively. For trio cohorts, pseudocontrols were defined from phased haplotypes prior to imputation.
