PIDD1 and attention deficit-hyperactivity disorder: We found significant associations of gene expression with ADHD for the same three genes in multiple brain tissues using MetaXcan: ARTN, PIDD1 showed increased expression (3.57 < Z-score <4.19 and 3.57 < Z-score < 5.37, respectively) and C2orf82 with a decreased expression (−3.64 < Z-score < −3.07) (Table S7), all of them surviving the Bonferroni correction.