Abstract
The 7-repeat allele of the DRD4 exon-3 VNTR (DRD4*7) is one of the most intensely studied polymorphisms in genetics studies of be- havioral phenotypes. Associations with a wide range of personality traits and psychopathologies have been postulated and, in particular, the association with ADHD is widely believed to be one of the strongest findings in psychiatric genetics. Although considerable work has been done on DRD4 in small clinical samples, the rela- tionship between the alleles of this gene and quantitative measures of behavior in a large population-based sample have never been studied. We have genotyped the majority of participants in the Dunedin multidisciplinary health and development study, a 26-year longitudinal study of a phenotypically well-characterized birth cohort (n = 1037), and carried out preliminary analysis on the data. Initial findings seem to down play the role of DRD4*7 in hyperactivity but support an association with quantitative and categorical measures of alcoholism, as well as negative emotionality personality traits.