Another possible explanation is that other candidate genes, quantitative traits, and/or environmental factors that we did not examine are stronger moderators of genetic risk for binge eating. For example, BDNF is an important regulator of food intake (Lebrun et al., 2006), and some studies implicate BDNF genes in the genetic diathesis of BN and the severity of bulimic behaviors (Ribases et al., 2005; Monteleone et al., 2006b). Given BDNF's role in appetite and weight regulation (Hashimoto et al., 2005), individuals with risk variants of this gene may be more susceptible to the effects of dietary restraint. Thus, BDNF genes may be promising candidates for gene-dietary restraint interactions. Dopaminergic genes may also be involved in interactive relationships that increase risk for binge eating and/or BN. There is some evidence to implicate dopamine genes in risk for BN (Shinohara et al., 2004), and these genes have also been associated with novelty seeking/impulsive personality traits (e.g., Benjamin et al., 1996; Schinka et al., 2002). Thus, dopaminergic genes may interact with impulsivity levels to increase risk for binge eating and other BN behaviors
