Earlier research has identified schizophrenia risk genes that encode nNOS and several downstream effectors of nNOS.7, 22, 23, 24 However, we found no changes in total NOS activity (with undetectable iNOS activity) and nNOS protein expression, but reduced eNOS protein levels, in BA8 of patients with schizophrenia. Here, NOS1 is linked to schizophrenia.