THE ASSOCIATION BETWEEN THE DOPAMINE D-4 RECEPTOR (D4DR) 16 AMINO-ACID REPEAT POLYMORPHISM AND NOVELTY SEEKING

Ebstein and colleagues have recently reported a significant associatio n between the 7-repeat allele of the dopamine D4 receptor (D4DR) 16 am ino acid repeat polymorphism and the personality trait of Novelty Seek ing (NS) in 124 Israeli subjects. This study, and another study conduc ted in the US (although with a different personality measure) that obs erved a similar association, have generated wide interest in the ident ification of the genes involved in personality variation. We have dete rmined D4DR genotypes in two groups of Finnish subjects; 193 psychiatr ically screened normal controls and 138 alcoholic offenders and assess ed NS with the Tridimensional Personality Questionnaire (TPQ). In norm als, we find no significant association between NS and the 7-repeat al lele despite similar allele frequencies and the use of the same person ality measure as Ebstein et al. The group of alcoholic offenders have significantly higher NS than normals, however we fail to replicate the previous association in this group and, in fact, find a significant a ssociation in the opposite direction as previously observed. These dat a suggest that D4DR may require re-evaluation as a candidate gene for personality variation.