INS and attention deficit-hyperactivity disorder: Moreover, positive genetic covariance was highlighted between AN and T2DM through the Reactome insulin processing gene set (p = 3.77 × 10−5), as well as between ADHD and MetS through the Reactome regulation of insulin secretion gene set (p = 1.18 × 10−4) (see Table 3; detailed results are shown in Tables S3–S11).