DAOA and psychiatric disorder: COMT and DAOA may contribute to the pathophysiology of psychiatric disorders by combining dopaminergic and glutamatergic pathways, and detrimental genotypes of both Val158Met COMT (Val allele) and DAOA (rs1421292; T allele), suggesting that healthy controls carrying risk genotypes of both COMT and DAOA would be expected to have less efficient response in PFC [18], [19].