No significant associations between two dopamine receptor polymorphisms and normal temperament

A replicated association has been reported between the normal personality trait of novelty seeking on the Tridimensional Personality Questionnaire (TPQ) and an exon III polymorphism in the dopamine D4 receptor gene (D4DR). Genotyping of a polymorphism in exon I of the same gene was carried out in 124 normal volunteers, and no association was found with any TPQ trait. In the same volunteers a dopamine D3 receptor gene (D3DR) point mutation in exon 1 was genotyped. Again, no overall association between any TPQ trait and alleles or genotype was found. There was a weak association between D3DR exon I genotype and harm avoidance in males only.