effect is mediated by its modulation of exposure to smoking continues to be explored.178 Finally, there appears to be an emergence of disordered gambling in patients receiving dopamine replacement therapy for Parkinson's disease—there is some evidence that dopaminergic stimulation interacts with variants in dopamine genes (for example, DAT, DRD3 and DRD4) to induce reward-seeking behaviors, particularly pathological gambling, but these genetic connections are speculative.179
