COMT and schizophrenia: Therefore, we investigated the impact of four SNPs, which were previously linked to sensorimotor gating and schizophrenia, on PPI in a new and independent sample of healthy human volunteers: The linked 5-HT2AR T102C/A-1438 G, the COMT Val158Met, and the NRG-1 Arg38Gln polymorphisms.