a direct comparison difficult [80]. Since the original association was only found in transdermal patch efficacy, the addition of a second NRT type may be a confounding factor when directly comparing the findings to other studies. The contradictory findings of these four studies make it difficult to draw conclusions about the role of the A118G variant in smoking cessation. However, previous studies have still indicated several mechanisms by which A118G genotype may affect biochemical reactions to nicotine use and suggest that further pharmacogenetic studies are warranted.
