The CYP1A2*1C, CYP1A2*1D and CYP1A2*1E alleles were identified in 0.4–4%, 3.4–11% and 0.4–6% of the Caucasian populations [44]; however, these alleles were detected neither in the tissue donors nor in the patients with psychiatric disorders. Here, CYP1A2 is linked to psychiatric disorder.