later, more problematic stages of cannabis involvement (i.e. dependence symptoms) cannot be disentangled from their effects on cannabis use. As a corollary, the high rate of cannabis use in CATS precluded any study of contributors to its variance. Therefore, we can only conclude that the interaction between rs604300 and childhood abuse may be related to both onset of cannabis use as well as misuse. This is consistent with twin epidemiological studies that document a high degree of genetic overlap between these stages of cannabis involvement (Agrawal et al., 2012).
