Imputation was performed using 1000 Genomes Project data30 to identify additional supportive SNPs within the top signals from each meta-analysis. Q-Q plots of the primary and secondary meta-analyses incorporating imputed data demonstrated minimal inflation of the median test statistic (Figure S15). No imputed SNPs in either meta-analysis surpassed the genome-wide significant threshold of p< 5×10−8. rs7868992 remained the top SNP overall, although its p-value dropped to 3.61 × 10−7 following imputation (Figure S9c).
