Using Affymetrix 6.0 genotype data that passed overall quality control metrics for each participant, we assessed alleles at the 12,058 SNPs that comprised the previously described v1.0 quit success score. The SNP names, chromosomal location, abstinence-associated allele and weight used in contributing to the total v1.0 score is detailed in Supplemental Information from Uhl and colleagues (2014). SNPs included in the score displayed nominally-significant association with ability to abstain in at least one of three smoking cessation success clinical trials that enrolled largely African- and European-American smokers whose allele frequencies, taken together, were similar to those of African and European-Americans in the current sample (Uhl et al., 2010; Rose et al., 2010). Greater weights were applied to alleles associated with quit success in multiple independent samples. We reasoned that, while genome-wide multiple tests result in false positive associations in single samples, fewer false positive associations would be identified in multiple samples. Genotype scores were included in the present analysis as a continuous variable. A higher score indicated a) greater success in smoking cessation as an interaction with nicotine replacement dose in one independent study in which dose was assigned randomly.
