Influence of serotonin 3A and 3B receptor genes on clozapine treatment response in schizophrenia

Earlier results suggest a minor role of variants in the serotonin 3 receptor (HTR3) subunit genes on antipsychotic treatment outcome of schizophrenia patients. In this study, we further investigated the role of the subunits A and B of the HTR3 receptor using 140 schizophrenia patients taking clozapine for 6 months. We have found significant allelic association of clozapine response with three variants in the HTR3A receptor (rs2276302, rs1062613, rs1150226) although only rs1062613 association remained significant after permutations (permutated P = 0.041). Moreover, rs2276302 and rs1062613 have shown nominally significant genotypic association. The two haplotypes composed of rs2276302-rs1062613-rs1150226 were also nominally significant. Taken together, our results suggest that variants in the HTR3A receptor gene can play a role in the treatment outcome of clozapine in schizophrenia patients that are refractory or intolerant of typical antipsychotic therapy. Further studies are necessary to confirm the reported associations. Pharmacogenetics and Genomics 20:274-276 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.