ABO and influenza: Of these, only one was associated with reported influenza infection (P < 0.05/24 = 0.002), despite adequate power for most (Supplementary Table 3): rs505922 in ABO (odds ratio (OR) = 1.05 for the T allele, 95% confidence interval (CI) = 1.02–1.07, P = 2.2 × 10−4; heterogeneity test P = 0.13; Fig. 1).