References

• Fleeman N, McLeod C, Bagust A, Beale S, Boland A, Dundar Y, et al. The clinical effectiveness and cost-effectiveness of testing for cytochrome P450 polymorphisms in patients with schizophrenia treated with antipsychotics: a systematic review and economic evaluation. Health Technol Assess. 2010; 14(3):1–157.
   PubMed Web of Science ®Google Scholar
• Arranz MJ, de Leon J. Pharmacogenetics and pharmacogenomics of schizophrenia: a review of last decade of research. Mol Psychiatry 2007; 12(8):707–47.
   PubMed Web of Science ®Google Scholar
• Zhou SF, Wang B, Yang LP, Liu JP. Structure, function, regulation and polymorphism and the clinical significance of human cytochrome P450 1A2. Drug Metab Rev 2010; 42(2):268–354.
   PubMed Web of Science ®Google Scholar
• Zhou SF, Yang LP, Zhou ZW, Liu YH, Chan E. Insights into the substrate specificity, inhibitors, regulation, and polymorphisms and the clinical impact of human cytochrome P450 1A2. AAPS J. 2009; 11(3):481–94.
   PubMed Web of Science ®Google Scholar
• Rendic S, Di Carlo FJ. Human cytochrome P450 enzymes: a status report summarizing their reactions, substrates, inducers, and inhibitors. Drug Metab Rev 1997; 29(1–2):413–580.
   PubMed Web of Science ®Google Scholar
• Lin JH, Lu AY. Inhibition and induction of cytochrome P450 and the clinical implications. Clin Pharmacokinet 1998; 35(5):361–90.
   PubMed Web of Science ®Google Scholar
• Sachse C, Brockmoller J, Bauer S, Roots I. Functional significance of a C—>A polymorphism in intron 1 of the cytochrome P450 CYP1A2 gene tested with caffeine. Br J Clin Pharmacol 1999; 47(4):445–9.
   PubMed Web of Science ®Google Scholar
• Lieberman JA, Safferman AZ, Pollack S, Szymanski S, Johns C, Howard A, et al. Clinical effects of clozapine in chronic schizophrenia: response to treatment and predictors of outcome. Am J Psychiatry 1994; 151(12):1744–52.
   PubMed Web of Science ®Google Scholar
• Lindstrom LH. The effect of long-term treatment with clozapine in schizophrenia: a retrospective study in 96 patients treated with clozapine for up to 13 years. Acta Psychiatr Scand 1988; 77(5):524–9.
   PubMed Web of Science ®Google Scholar
• Asenjo Lobos C, Komossa K, Rummel-Kluge C, Hunger H, Schmid F, Schwarz S, et al. Clozapine versus other atypical antipsychotics for schizophrenia. Cochrane Database Syst Rev 2010; (11):CD006633.
   Google Scholar
• Uzun O, Ozsahin A, Ozmenler KN, Doruk A, Battal S. Clozapine in treatment-resistant schizophrenia: Followed-up study for three years. Klinik Psikofarmakoloji Bulteni -Bulletin of Clinical Psychopharmacology 2000; 10(2):74–80.
   Google Scholar
• Citak S, Cakici ET, Cakici M. Neuropsychological assessment in schizophrenic patients treated with haloperidol or clozapine. Klinik Psikofarmakoloji Bulteni -Bulletin of Clinical Psychopharmacology 2000; 19(1):5–14.
   Google Scholar
• Breier A, Buchanan RW, Kirkpatrick B, Davis OR, Irish D, Summerfelt A, et al. Effects of clozapine on positive and negative symptoms in outpatients with schizophrenia. Am J Psychiatry 1994; 151(1):20–6.
   PubMed Web of Science ®Google Scholar
• Carpenter WT, Jr., Conley RR, Buchanan RW, Breier A, Tamminga CA. Patient response and resource management: another view of clozapine treatment of schizophrenia. Am J Psychiatry 1995; 152(6):827–32.
   Web of Science ®Google Scholar
• Xu M, Xing Q, Li S, Zheng Y, Wu S, Gao R, et al. Pharacogenetic effects of dopamine transporter gene polymorphisms on response to chlorpromazine and clozapine and on extrapyramidal syndrome in schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry 2010; 34(6):1026–32.
   PubMed Web of Science ®Google Scholar
• Melkersson KI, Gunes A, Dahl ML. Impact of serotonin receptor 2A gene haplotypes on C-peptide levels in clozapine- and olanzapine- treated patients. Hum Psychopharmacol 2010; 25(4):347–52.
   Web of Science ®Google Scholar
• Souza RP, de Luca V, Meltzer HY, Lieberman JA, Kennedy JL. Influence of serotonin 3A and 3B receptor genes on clozapine treatment response in schizophrenia. Pharmacogenet Genomics 2010; 20: 274–6.
   PubMed Web of Science ®Google Scholar
• Hwang R, Zai C, Tiwari A, Muller DJ, Arranz MJ, Morris AG, et al. Effect of dopamine D3 receptor gene polymorphisms and clozapine treatment response: exploratory analysis of nine polymorphisms and meta-analysis of the Ser9Gly variant. Pharmacogenomics J 2010; 10: 200–18.
   PubMed Web of Science ®Google Scholar
• Souza RP, Tampakeras M, Basile V, Shinkai T, Rosa DV, Potkin S, et al. Lack of association of GPX1 and MnSOD genes with symptom severity and response to clozapine treatment in schizophrenia subjects. Hum Psychopharmacol 2009; 24(8):676–9.
   Web of Science ®Google Scholar
• Consoli G, Lastella M, Ciapparelli A, Catena Dell'Osso M, Ciofi L, Guidotti E, et al. ABCB1 polymorphisms are associated with clozapine plasma levels in psychotic patients. Pharmacogenomics 2009; 10(8):1267–76.
   PubMed Web of Science ®Google Scholar
• Kohlrausch FB, Salatino-Oliveira A, Gama CS, Lobato MI, Belmontede-Abreu P, Hutz MH. G-protein gene 825C > T polymorphism is associated with response to clozapine in Brazilian schizophrenics. Pharmacogenomics 2008; 9(10):1429–36.
   Web of Science ®Google Scholar
• Barlas IO, Cetin M, Erdal ME, Semiz UB, Basoglu C, Ay ME, et al. Lack of Association Between DRD3 Gene Polymorphism and Response to Clozapine in Turkish Schizoprenia Patients. Am J Med Genet B 2009; 150B(1):56–60.
   Web of Science ®Google Scholar
• Arranz MJ, Dawson E, Shaikh S, Sham P, Sharma T, Aitchison K, et al. Cytochrome P4502D6 genotype does not determine response to clozapine. Br J Clin Pharmacol 1995; 39(4):417–20.
   PubMed Web of Science ®Google Scholar
• Ozdemir V, Kalow W, Okey AB, Lam MSM, Albers LJ, Reist C, et al. Treatment-resistance to clozapine in association with ultrarapid CYP1A2 activity and the C -> A polymorphism in intron 1 of the CYP1A2 gene: Effect of grapefruit juice and low-dose fluvoxamine. J Clin Psychopharm 2001; 21(6):603–7.
   PubMed Web of Science ®Google Scholar
• Kootstra-Ros JE, Smallegoor W, van der Weide J. The cytochrome P450 CYP1A2 genetic polymorphisms *1F and *1D do not affect clozapine clearance in a group of schizophrenic patients. Ann Clin Biochem 2005; 42(Pt 3):216–9.
   PubMedGoogle Scholar
• Eap CB, Bender S, Jaquenoud Sirot E, Cucchia G, Jonzier-Perey M, Baumann P, et al. Nonresponse to clozapine and ultrarapid CYP1A2 activity: clinical data and analysis of CYP1A2 gene. J Clin Psychopharmacol 2004; 24(2):214–9.
   PubMed Web of Science ®Google Scholar
• van der Weide J, Steijns LS, van Weelden MJ. The effect of smoking and cytochrome P450 CYP1A2 genetic polymorphism on clozapine clearance and dose requirement. Pharmacogenetics 2003; 13(3):169–72.
   PubMedGoogle Scholar
• Sirot EJ, Knezevic B, Morena GP, Harenberg S, Oneda B, Crettol S, et al. ABCB1 and Cytochrome P450 Polymorphisms Clinical Pharmacogenetics of Clozapine. J Clin Psychopharm 2009; 29(4):319–26.
   Web of Science ®Google Scholar
• Kane J, Honigfeld G, Singer J, Meltzer H. Clozapine for the Treatment-Resistant Schizophrenic—a Double-Blind Comparison with Chlorpromazine. Arch Gen Psychiat 1988; 45(9):789–96.
   PubMed Web of Science ®Google Scholar
• Overall JE, Gorham DR. The Brief Psychiatric Rating-Scale. Psychol Rep 1962; 10(2):799–812.
   Google Scholar
• Andreasen NC, Flaum M, Swayze VW, Tyrrell G, Arndt S. Positive and Negative Symptoms in Schizophrenia—a Critical Reappraisal. Arch Gen Psychiat 1990; 47(7):615–21.
   PubMed Web of Science ®Google Scholar
• Andreasen NC. The Scale for the Assessment of Negative Symptoms (SANS): conceptual and theoretical foundations. Br J Psychiatry Suppl 1989: (7):49–58.
   Google Scholar
• Livak KJ. Allelic discrimination using fluorogenic probes and the 5′ nuclease assay. Genet Anal 1999; 14(5–6):143–9.
   PubMedGoogle Scholar
• Nordmark A, Lundgren S, Ask B, Granath F, Rane A. The effect of the CYP1A2 *1F mutation on CYP1A2 inducibility in pregnant women. Br J Clin Pharmacol 2002; 54(5):504–10.
   PubMed Web of Science ®Google Scholar
• Schulze TG, Schumacher J, Muller DJ, Krauss H, Alfter D, Maroldt A, et al. Lack of association between a functional polymorphism of the cytochrome P450 1A2 (CYP1A2) gene and tardive dyskinesia in schizophrenia. Am J Med Genet 2001; 105(6):498–501.
   PubMed Web of Science ®Google Scholar
• Bertilsson L, Carrillo JA, Dahl ML, Llerena A, Alm C, Bondesson U, et al. Clozapine disposition covaries with CYP1A2 activity determined by a caffeine test. Br J Clin Pharmacol 1994; 38(5):471–3.
   PubMed Web of Science ®Google Scholar
• Buur-Rasmussen B, Brosen K. Cytochrome P450 and therapeutic drug monitoring with respect to clozapine. Eur Neuropsychopharmacol 1999; 9(6):453–9.
   PubMed Web of Science ®Google Scholar
• Hasegawa M, Gutierrez-Esteinou R, Way L, Meltzer HY. Relationship between clinical efficacy and clozapine concentrations in plasma in schizophrenia: effect of smoking. J Clin Psychopharmacol 1993; 13(6):383–90.
   PubMed Web of Science ®Google Scholar