title: Association between the type 4 dopamine receptor gene polymorphism and novelty seeking.
abstract: OBJECTIVE
  Mixed results have been reported on the association between the type 4 dopamine receptor gene (DRD4) and the temperament dimension of novelty seeking. We tested this association by specifying the analysis to components of novelty seeking.
  
  
  METHODS
  Participants were 150 high and low novelty-seeking scorers (the highest and lowest 10%) from a randomized, population-based sample of Finnish citizens in six age cohorts. We genotyped a 48-bp repeat polymorphism in the DRD4 gene. Novelty seeking was assessed by the Temperament and Character Inventory.
  
  
  RESULTS
  No difference in overall novelty seeking between individuals with no seven-repeat allele (short) and any seven-repeat allele (long), between the 4,4 and 4,7 genotype groups, and between long (l/l and s/l) and short (s/s) polymorphism groups were found. The odds ratio for high overall novelty seeking in the presence of any two- or five-repeated alleles vs. none was 2.41 (95% CI, 1.11-5.20). Corresponding odds ratios were significant for exploratory excitability (2.94; 95% CI, 1.32-6.59) and impulsiveness (2.74; 95% CI, 1.23-6.11) but not for other components of novelty seeking. No interactions with age or gender were detected.
  
  
  CONCLUSIONS
  The present study confirmed previous findings on the association between the type 4 dopamine receptor gene and novelty seeking, in particular exploratory excitability and impulsiveness. The tendency to avoid or approach a novel situation is a core concept of several temperamental theories. The present findings support the hypothesis that this tendency is associated with DRD4 and might concern temperament psychology in general, not only the concept of novelty seeking.
authors.affiliation: Department of Psychology, University of Helsinki, Helsinki, Finland. liisa.keltikangas-jarvinen@helsinki.fi
authors.forename: Liisa
authors.initials: L
authors.lastname: Keltikangas-Järvinen
authors.forename: Marko
authors.initials: M
authors.lastname: Elovainio
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
authors.forename: Dirk
authors.initials: D
authors.lastname: Lichtermann
authors.forename: Jesper
authors.initials: J
authors.lastname: Ekelund
authors.forename: Leena
authors.initials: L
authors.lastname: Peltonen
mesh_terms: D000328:Adult; D000483:Alleles; D004522:Educational Status; D005106:Exploratory Behavior / Q000502:physiology*; D005260:Female; D005387:Finland; D005838:Genotype; D006801:Humans; D007175:Impulsive Behavior / Q000235:genetics; D008297:Male; D018598:Minisatellite Repeats; D011446:Prospective Studies; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4
chemical_list: C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4