Association between the type 4 dopamine receptor gene polymorphism and novelty seeking.
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.
Keltikangas-Järvinen
Liisa
L
Department of Psychology, University of Helsinki, Helsinki, Finland. liisa.keltikangas-jarvinen@helsinki.fi
Elovainio
Marko
M
Kivimäki
Mika
M
Lichtermann
Dirk
D
Ekelund
Jesper
J
Peltonen
Leena
L
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
C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4