Accounting for multiple testing only within a single endophenotype (0.05/127 = 3.9 × 10−4), we found two SNPs associated with an endophenotype. SNP rs17194490 (reference = G, alternate = T) was associated both with antisaccade and P300. The alternate allele decreased antisaccade errors (β = −0.12, p = 2.3 × 10−4, alternate allele frequency = 0.163) and increased amplitude on the P300 genetic factor (β = 0.12, p = 2.7 × 10−4). The alternate allele in SNP rs7267348 (reference allele = T, alternate = C) decreased beta EEG power (β = −0.11, p = 3.8 × 10−4, alternate allele frequency = 0.25). Neither variant survived multiple testing for more than a single endophenotype. Summary statistics for all 127 variant associations with all 17 endophenotypes are shown in online Supplementary Table S5.
