ITIH4 and schizophrenia: Other clusters of genes encoding proteins present within the fetal PPIN included (Table S4) (1) metabolic traits associated with FADS1/2; (2) traits linked with cognition and worry that associated with two gene clusters (TMEM110, GNL3, STAB1 and ITIH4, NEK4, NT5DC2) located at chromosome 3p21.31; and (3) multiple genes across different locations associated with schizophrenia (Fig 3).