title: Do obsessive-compulsive disorder and Tourette syndrome share a common susceptibility gene? An association study of the BDNF Val66Met polymorphism in the Chinese Han population.
abstract: OBJECTIVE
  We explored the association between the BDNF Val66Met polymorphism and susceptibility to both obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) in the Chinese Han population.
  
  
  METHODS
  Genotyping for the BDNF Val66Met polymorphism was performed in 321 OCD patients and 426 healthy control subjects and case-control association study data were analysed. Additionally, we evaluated the genetic contribution of this variant in 331 TS patients (including 267 TS trios) and 519 controls using the transmission disequilibrium test (TDT) and case-control study.
  
  
  RESULTS
  A statistically significant difference was found in the genetic contribution of the BDNF Val66Met polymorphism between both the OCD (χ(2) = 7.50, P = 0.023 by genotype; χ(2) = 6.67, P = 0.01 by allele) and TS (χ(2) = 6.76, P = 0.03 by genotype; χ(2) = 4.27, P = 0.04 by allele), and control groups. TDT and GHRR analysis for TS trios also showed a significant transform disequilibrium of this polymorphism (TDT: χ(2) = 3.96, P = 0.05; HHRR: χ(2) = 4.33 P = 0.04; GHRR: χ(2) = 5.74, P = 0.02; χ(2) = 0.98, P = 0.37). There was also a significant gender trend between patients and controls in female cases for OCD and in male cases for TS.
  
  
  CONCLUSIONS
  Our study supports the involvement of the BDNF Val66Met polymorphism as a common genetic susceptibility for OCD and TS in the Chinese Han population, showing specific gender trends.
authors.affiliation: a Genetic Laboratory, The Affiliated Hospital of Qingdao University , Qingdao , China.|b Prenatal Diagnosis Center, The Affiliated Hospital of Qingdao University , Qingdao , China.
authors.forename: Shiguo
authors.initials: S
authors.lastname: Liu
authors.affiliation: c Department of Psychiatry , Medical College, Qingdao University , Qingdao , China.
authors.forename: Jiajia
authors.initials: J
authors.lastname: Cui
authors.affiliation: d Department of Gynecology , The Affiliated Hospital of Qingdao University , Qingdao , China.
authors.forename: Zhaoyuan
authors.initials: Z
authors.lastname: Niu
authors.affiliation: e Child Healthcare Department, The Affiliated Hospital of Qingdao University , Qingdao, China, Qingdao University , Qingdao , China.
authors.forename: Mingji
authors.initials: M
authors.lastname: Yi
authors.affiliation: c Department of Psychiatry , Medical College, Qingdao University , Qingdao , China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhang
authors.affiliation: f Department of Neurology , Linyi People's Hospital, Shandong University , Linyi , People's Republic of China.
authors.forename: Fengyuan
authors.initials: F
authors.lastname: Che
authors.affiliation: g Graduate School, Peking Union Medical College , Beijing , China.|h National Research Institute for Family Planning , Beijing , China.|i World Health Organization Collaborating Centre for Research in Human Reproduction , Beijing , China.
authors.forename: Xu
authors.initials: X
authors.lastname: Ma
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D044466:Asian People; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D016022:Case-Control Studies; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012737:Sex Factors; D005879:Tourette Syndrome / Q000235:genetics*; D055815:Young Adult
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human
keywords: BDNF; Polymorphism; Tourette syndrome; common susceptibility; obsessive–compulsive disorder