We divided individuals into six strata by assigning them a unique phenotype using the hierarchy: 1) schizophrenia (SZ), 2) bipolar disorder (BP), 3) autism spectrum disorder (ASD), 4) attention deficit hyperactivity disorder (ADHD), 5) major depressive disorder (MDD) and 6) controls (ICON). We assumed a dominant model, where homozygous and heterozygous carriers of the minor allele of rs56372821 were treated equally. See Supplementary Table 9 for distribution of individuals having the major allele or at least one minor allele among the strata.
