The goal of pharmacogenetic studies of smoking cessation therapy is to help increase the likelihood of an individual quitting smoking, and reduce the likelihood of adverse effects of smoking cessation therapy by individualizing treatment strategies according to genetic profile. Although pharmacogenetic tests for some conditions have had successful application in clinical practice (Mallal et al, 2008; Relling et al, 1999), this has not been without challenges (Higgs et al, 2010; Ikediobi et al, 2009). Even leaving aside issues of cost-effectiveness and concerns around tests that could result in effective therapies being withheld (Epstein et al, 2009), several important issues need to be considered before pharmacogenetic testing for selection of smoking cessation treatment becomes standard clinical practice. Multiple genes and environmental factors probably combine to influence the response to smoking cessation therapies, yet most pharmacogenetic studies currently focus on a limited set of alleles and/or single genes and have limited power to account for gene–gene and gene–environment interactions. The development of effective individualized treatments for smoking cessation will likely require that future pharmacogenetic studies evaluate these multifactorial interactions. However, despite such
