Association between a promoter dopamine D2 receptor gene variant and the personality trait detachment

Background: Personality traits have shown considerable heritable components. Striatal dopamine D-2 receptor density, as determined by positron-emission tomography, has been associated with detached personality, as assessed by the Karolinska Scales of Personality. A putative functional promoter polymorphism in the dopamine D2 receptor gene (DRD2), -141C ins/del, has been associated with dopamine D2 receptor density. Methods: In this study healthy subjects (n = 235) who filled in at least one of several personality questionnaires (Karolinska Scales of Personality, Swedish Universities Scales of Personality, Health-relevant Five-factor Personality Inventory, and Temperament and Character Inventory) were analyzed with regard to the DRD2 -141C ins/del variant. Results: There was an association (p = .001) between the DRD2 -141C ins/del variant and Karolinska Scales of Personality Detachment scale, indicating higher scores in subjects with the -141C del variant. There were also associations between the DRD2 -141C ins/del variant and a number of Karolinska Scales of Personality and Swedish Universities Scales of Personality Neuroticism-related scales, but of these only Swedish Universities Scales of Personality Lack of Assertiveness scale (p = .001) survived correction for multiple testing. Conclusions: These results add further support for the involvement of dopamine D2 receptor in certain personality traits. The results should be treated with caution until replicated. (C) 2003 Society of Biological Psychiatry.