We made the hypothesis that phenotypical heterogeneity of alcohol-dependence (i.e. the DRD3 gene is a vulnerability gene in a specific subgroup of patients only) could explain these spurious findings, focusing on a core dimension of addictive disorders, namely impulsiveness.
In this study we report an association of the dopamine D3 receptor (DRD3) polymorphism with impulsiveness according to Eysenck's EIQ and scores on the German short version of the Wender Utah Rating Scale (WURS-k), which we used for the assessment of a history of ADHD-related symptoms.