SNPs were selected for the replication study based on (i) suggestive association (P ≤ 0.0001) in the meta-analysis of GWAS cohorts 1 and 2, and (ii) nominal (P < 0.05) and same direction of association in both GWAS cohorts. A total of 59 SNPs were successfully genotyped for replication. In addition, rs815611 showed nominal associations in both GWAS cohorts and was genotyped to confirm the association result of the highly correlated SNP rs2033195 (r2 = 0.94 in our GWAS samples). Genotyping of samples from replication cohorts 3–6 was performed using the iPLEX Sequenom MassARRAY platform (San Diego, CA). The minimum and average SNP call rates were 81 and 96%, respectively. The average genotype concordance rate of 45 blind duplicates was 99.8%. All SNPs had Hardy–Weinberg P values ≥0.001 in the combined unrelated replication cohorts. For related samples, genotype data identified as Mendelian inconsistencies by PedCheck (v. 1.1) (http://watson.hgen.pitt.edu/register/docs/ pedcheck.html) were removed.
