NRG1 and schizophrenia: Additionally, in a clinical study of a 2-week treatment of first-onset patients with schizophrenia (who had not taken antipsychotics before) with the antipsychotics risperidone and quetiapine, the NRG1 mRNA expression of peripheral blood lymphocytes (PBLs) gradually and significantly increased after therapy, compared with the pretreatment levels [16].