SHANK2 and attention deficit-hyperactivity disorder: As shown in Table 3, at the gene-level, SHANK2, compared to the aggregated control sample, was associated with the ADHD group (p = 0.0082), the enlarged ADHD sample (i.e., involving both ADHD and ADHD + ASD groups) (p = 0.0034), and finally the aggregated clinical sample (p = 0.0031 and permuted p = 0.0061).