size heterogeneity between ancestries. Effect heterogeneity was also assessed using the multi-ethnic study population of PAGE by first identifying the lead SNP in each locus with the smallest P value in PAGE, totalling 333 SNPs (302 known loci from the GWAS Catalog, plus 31 novel loci discovered in the present analysis). Among the 333 lead SNPs, 24 (7.2%) had a significant Bonferroni-corrected SNP × PC interaction heterogeneity P value (P < 1.5 × 10−4, 0.05/333).
