title: Fat-mass and obesity-associated gene polymorphisms and weight gain after risperidone treatment in first episode schizophrenia.
abstract: BACKGROUND
  Obesity induced by antipsychotics severely increases the risk of many diseases and significantly reduces quality of life. Genome Wide Association Studies has identified fat-mass and obesity-associated (FTO) gene associated with obesity. The relationship between the FTO gene and drug-induced obesity is unclear.
  
  
  METHODS
  Two hundred and fifty drug naïve, Chinese Han patients with first-episode schizophrenia were enrolled in the study, and genotyped for four single nucleotide polymorphisms (SNPs rs9939609, rs8050136, rs1421085 and rs9930506) by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing. Body weight and body mass index (BMI) were measured at baseline and six months after risperidone treatment.
  
  
  RESULTS
  At baseline, body weight and BMI of TT homozygotes were lower than those of A allele carriers in rs9939609; body weight of AA homozygotes was higher than those of G allele carriers in rs9930506 (p's < 0.05). After 6 months of risperidone treatment, body weight and BMI of TT homozygotes were lower than those of A allele carriers in rs9939609 (p's <0.01); body weight and BMI of CC homozygotes were lower than those of A allele carriers in rs8050136 (p's < 0.05); body weight of AA homozygotes was higher than those of G allele carriers in rs9930506 (p's < 0.05). After controlling for age, gender, age of illness onset, disease duration, weight at baseline and education, weight gain of TT homozygotes at 6 months remained to be lower than those of A allele carriers in rs9939609 (p < 0.01); weight gain of CC homozygotes at 6 months was lower than those of A allele carriers in rs8050136 (p = 0.01). Stepwise multiple regression analysis suggested that, among 4 SNPs, rs9939609 was the strongest predictor of weight gain after 6 months of risperidone treatment (p = 0.001).
  
  
  CONCLUSIONS
  The FTO gene polymorphisms, especially rs9939609, seem to be related to weight gain after risperidone treatment in Chinese Han patients with first episode schizophrenia.
authors.affiliation: The first Affiliated Hospital/Zhengzhou University, Zhengzhou, China. sxqzhll@126.com.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Song
authors.forename: Lijuan
authors.initials: L
authors.lastname: Pang
authors.forename: Yufang
authors.initials: Y
authors.lastname: Feng
authors.forename: Xiaoduo
authors.initials: X
authors.lastname: Fan
authors.forename: Xue
authors.initials: X
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Jinsong
authors.initials: J
authors.lastname: Gao
authors.forename: Jianjiang
authors.initials: J
authors.lastname: Zhang
authors.forename: Katlyn
authors.initials: K
authors.lastname: Nemani
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Luxian
authors.initials: L
authors.lastname: Lv
mesh_terms: D000328:Adult; D000483:Alleles; D000071516:Alpha-Ketoglutarate-Dependent Dioxygenase FTO; D014150:Antipsychotic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D011506:Proteins / Q000235:genetics*; D018967:Risperidone / Q000494:pharmacology* / Q000627:therapeutic use; D012559:Schizophrenia / Q000188:drug therapy* / Q000235:genetics; D015430:Weight Gain / Q000187:drug effects* / Q000235:genetics*; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D011506:Proteins; D000071516:Alpha-Ketoglutarate-Dependent Dioxygenase FTO; C526492:FTO protein, human; D018967:Risperidone