High quality genetic risk information similar to that provided by the deCODE study, opens up exciting new avenues for investigating the functional role of specific nAChR subunits on central nervous system circuit plasticity and on the physiology of peripheral tissues affected by smoking. Studies on the role of α3 and α5 nicotinic receptor subunits in the primate habenula-interpeduncular tract,15,16 for example, represent a natural path for further inquiry, as this axis is involved in a variety of brain functions and behaviors that include reward phenomena, anxiety and depression.17 Thus, the connection provides fertile grounds for future investigations into the establishment and maintenance of smoking behaviors from the vantage point of the self-medication theory of (nicotine) addiction.
