CYP2C19 and schizophrenia: To explore the effects of CYP2C19 genotype on interindividual variabilities in serum concentrations of valproic acid in Chinese Han schizophrenia, the CYP2C19*2 (G681A, splicing defect) and CYP2C19*3 (G636A, W212X, premature stop codon) were analyzed by real-time PCR.