The interaction between serotonin receptor 2A and catechol-O-methyltransferase gene polymorphisms is associated with the novelty-seeking subscale impulsiveness.
OBJECTIVE
Novelty seeking is a trait that has been consistently associated with problem behaviours. There is evidence for heritability of novelty seeking, but the molecular genetic basis of the trait is still widely unclear.


METHODS
The interaction between polymorphisms of catechol-O-methyltransferase (COMT) and serotonin receptor 2A genes was examined in relation to novelty seeking and its different subscales in healthy Finnish adults. A subsample of 1214 participants derived from a population-based sample was genotyped for the COMT Val158Met (rs4680) and HTR2A T102C (rs6313) genes. Novelty seeking was measured twice, with a 4-year interval, using Cloninger's Temperament and Character Inventory.


RESULTS
The interaction between COMT Val158Met and HTR2A T102C polymorphisms was found to be associated with subscale impulsiveness. T/T carriers of HTR2A T102C polymorphism, that also had Met/Met genotype of COMT Val158Met single nucleotide polymorphism, scored significantly higher on impulsiveness than Val allele carriers (P=0.005).


CONCLUSIONS
Our results suggest that the interaction between dopaminergic and serotonergic genes might underlie impulsiveness. Together with earlier research our results also stress the importance of considering novelty seeking as a heterogeneous trait with its subscales having different genetic backgrounds.
Salo
Johanna
J
Department of Psychology, University of Helsinki, Helsinki, Finland.
Pulkki-Råback
Laura
L
Hintsanen
Mirka
M
Lehtimäki
Terho
T
Keltikangas-Järvinen
Liisa
L
D000293:Adolescent; D000328:Adult; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005106:Exploratory Behavior; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000201:enzymology* / Q000235:genetics*; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics*; D055815:Young Adult
D044402:Receptor, Serotonin, 5-HT2A; D002394:Catechol O-Methyltransferase