There are a number of stages of research that are necessary prior to the translation of pharmacogenetics research to practice, in the form of genetically tailored treatment (Shields et al., 2004). First, and most important, is the independent replication of findings across multiple studies. As pharmacogenetics and nicotine dependence is an emerging science, this criterion has yet to be achieved in most cases; however, evidence for associations of CYP2A6 with smoking behavior and for the nicotine-metabolite ratio as a predictor of relapse appear very promising. In addition to the demonstration of efficacy in independent settings, it is important to evaluate whether pharmacogenetic tailoring is more cost effective than simply providing medication to all smokers in treatment (Grossman, 2007; Shields et al., 2004). Cost effectiveness of implementing tailored therapy would depend on the distribution of the relevant genetic polymorphisms, costs involved in genotyping individuals, and subsequent effectiveness of the tailored versus untailored therapy (Roden et al., 2006). Our group recently completed a study in which cost effectiveness of smoking cessation tailored, based on genotype, was estimated and compared to the standard
