CYP1A2 and psychiatric disorder: The CYP1A2 genotype of the patients with psychiatric disorders was determined from CYP1A2 SNP data (including −3860G>A, −2467delT, −739T>G, −163C>A and 2159G>A) by haplotype analysis, whereas the hepatic CYP1A2 function was estimated from CYP1A2 mRNA expression in patients’ leukocytes.