title: Variable number tandem repeats in dopamine receptor D4 in Tourette's syndrome.
abstract: BACKGROUND
  We attempted to clarify the association between dopamine receptor D4 (DRD4) 48-bp variable number of tandem repeats (VNTR) polymorphism and Tourette's syndrome.
  
  
  METHODS
  The DRD4 48-bp VNTR polymorphism was genotyped in 291 Tourette's syndrome patients (including 218 trios) and 405 controls. Chi-square and transmission disequilibrium test analysis were used to compare genetic distributions. We retrieved related studies in a meta-analysis to clarify the role of 2-repeat and 4-repeat alleles in the pathogenesis.
  
  
  RESULTS
  Obvious genotype and allele distribution differences were observed between patients and healthy controls for both 2-repeat and 4-repeat alleles. This was verified using transmission disequilibrium test analysis. Meta-analysis showed strong associations in both the total population and the Asian population.
  
  
  CONCLUSIONS
  The DRD4 48-bp VNTR polymorphism appears to be associated with Tourette's syndrome, with the 2-repeat allele performing a protective role and the 4-repeat allele a nonprotective role in the genesis of the disease.
authors.affiliation: Genetic Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, 266003, China; Prenatal Diagnosis Center, The Affiliated Hospital of Qingdao University, Qingdao, 266003, China.
authors.forename: Shiguo
authors.initials: S
authors.lastname: Liu
authors.forename: Jiajia
authors.initials: J
authors.lastname: Cui
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhang
authors.forename: Weifeng
authors.initials: W
authors.lastname: Wu
authors.forename: Haitao
authors.initials: H
authors.lastname: Niu
authors.forename: Xu
authors.initials: X
authors.lastname: Ma
authors.forename: Hongmei
authors.initials: H
authors.lastname: Xu
authors.forename: Mingji
authors.initials: M
authors.lastname: Yi
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005192:Family Health; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D015201:Meta-Analysis as Topic; D018598:Minisatellite Repeats / Q000235:genetics*; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D005879:Tourette Syndrome / Q000235:genetics*; D055815:Young Adult
chemical_list: D050638:Receptors, Dopamine D4
keywords: TS dopamine receptor D4; VNTR; meta-analysis