Dopamine Receptor D4 Polymorphism Predicts the Effect of L-DOPA on Gambling Behavior

There is ample evidence that a subgroup of Parkinson’s disease patients who are treated with dopaminergic drugs develop certain behavioral addictions such as pathological gambling. The fact that only a subgroup of these patients develops pathological gambling suggests an interaction between dopaminergic drug treatment and individual susceptibility factors. These are potentially of genetic origin, since research in healthy subjects suggests that vulnerability for pathological gambling may be linked to variation in thedopamine receptor D4 (DRD4) gene. Using a pharmacogenetic approach, we investigated how variation in this gene modulates the impact of dopaminergic stimulation on gambling behavior in healthy subjects.