title: Lack of association between the -759C/T polymorphism of the 5-HT2C receptor gene and olanzapine-induced weight gain among Korean schizophrenic patients.
abstract: BACKGROUND
  Weight gain can be an adverse effect of antipsychotics that significantly affects long-term health and treatment compliance. Many reports have suggested that the 5-HT2C receptor gene (HTR2C) is related to appetite and eating behaviours associated with body weight change. We hypothesized that there was a relationship between the HTR2C -759C/T polymorphism and olanzapine-induced weight gain.
  
  
  METHODS
  Seventy-nine Korean schizophrenic patients were examined. Their weight was measured before starting olanzapine and after long-term treatment for at least 3 months. We controlled the use of drugs other than olanzapine except benzodiazepines and anticholinergics. Genotyping for the HTR2C -759C/T polymorphism was performed on all participants.
  
  
  RESULTS
  We found that long-term treatment with olanzapine resulted in mean gains in weight and BMI of 5.2 kg and 1.93 kg/m(2), respectively. However, body weight changes from baseline to the study endpoint were not significantly associated with genotypes. The frequency of the T allele did not differ significantly between subjects with weight gains below and above a clinically significant cutoff, defined as 7% relative to baseline (chi(2) = 0.213, P = 0.445), indicating that the T allele had no protective effect against olanzapine-induced weight gain.
  
  
  CONCLUSIONS
  The findings from this study do not support the presence of a relationship between the -759C/T polymorphism of the HTR2C gene and weight gain in Korean schizophrenic patients receiving olanzapine treatment.
authors.affiliation: Department of Neuropsychiatry, Inje University College of Medicine, Goyang, South Korea.
authors.forename: Y-M
authors.initials: YM
authors.lastname: Park
authors.forename: J-H
authors.initials: JH
authors.lastname: Cho
authors.forename: S-G
authors.initials: SG
authors.lastname: Kang
authors.forename: J-E
authors.initials: JE
authors.lastname: Choi
authors.forename: S-H
authors.initials: SH
authors.lastname: Lee
authors.forename: L
authors.initials: L
authors.lastname: Kim
authors.forename: H-J
authors.initials: HJ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000483:Alleles; D014150:Antipsychotic Agents / Q000009:adverse effects*; D001569:Benzodiazepines / Q000009:adverse effects*; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007723:Korea; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D011110:Polymorphism, Genetic; D044405:Receptor, Serotonin, 5-HT2C / Q000235:genetics*; D012559:Schizophrenia / Q000188:drug therapy*; D015430:Weight Gain / Q000187:drug effects* / Q000235:genetics
chemical_list: D014150:Antipsychotic Agents; D044405:Receptor, Serotonin, 5-HT2C; D001569:Benzodiazepines; D000077152:Olanzapine