Of 1,185,559 imputed SNPs that passed QC, 287 showed evidence for association in the discovery stage with P < 10-4. These variants represented 66 independent signals and had frequencies and effect sizes commensurate with observations in other common complex diseases. One variant, not surrounded by other SNPs achieving low p-values and for which genotypes were only available in two of the 15 initial study groups, surpassed genome-wide significance (rs4957798, P=1.67×10-12) but was not subsequently replicated in the global meta-analysis across discovery and replication samples. The overall λGC was 1.03 (Figures S3 and S4).Seventy-six SNPs (of which 72 were independent) were prioritized for follow-up through in silico and de novo replication (Table S5). Nine SNPs showed association with P < 0.05 (minimum p-value was 0.003) in the replication dataset meta-analysis (binomial P=0.0135) (Table S5). Based on 72 independent SNPs taken forward, we would expect 0.05×72=3.6 SNPs to reach P=0.05 by chance. The 0.0135 P value reflects this enrichment in signal. No signals surpassed genome-wide significance (P=5×10-8) in the final global meta-analysis across all discovery and replication samples (Table S5) or in the AN subtype analyses (Tables S6-S7).
