Our initial analysis focused on the subset of “current frequent smokers” which included individuals who reported using tobacco every day in the six months prior to interview. Our hypothesis for selection criteria seems to be supported because the strongest genetic association was detected in the comparison of dependence symptoms among daily smokers. Specifically, the mean number of symptoms in current frequent smokers with the genotype AA at rs7004381 is 2.2 ± 0.37 versus 3.4 ± 0.17 symptoms in GG individuals.
