OBJECTIVE: Personality traits in human subjects have shown considerable
heritable components. Recently, two research groups reported associations
between dopamine D4 receptor genotypes and the personality trait known as
novelty seeking. This study was an attempt to replicate these findings.
METHOD: Three different exonic dopamine D4 receptor polymorphisms were
genotyped in 126 healthy Swedish subjects. Personality traits of the
subjects were assessed with the Karolinska Scales of Personality. RESULTS:
Although there was a tendency in the direction hypothesized, no significant
association between genotype constellations and personality traits was
found. CONCLUSIONS: The previously reported association between dopamine D4
receptor alleles and novelty seeking was not replicated. Possible reasons
for this include differences in personality inventories, ethnicity, and
type I or type II errors.