Diagram outlining the analyses undertaken in this report. (left) Comparisons between allele frequency assessments at 520,000 genomic SNPs in the whole group of European American nicotine dependent subjects who volunteered for inclusion in nicotine cessation trials in comparison to SNP frequency assessments for European-American control research volunteers without histories of any substantial use of any addictive substance. The preplanned analysis of this data focused on the extent to which these nominally positive SNPs added to the significance of the results of previously assembled convergent data from studies of other four other addict vs control comparisons. Genes for which the Monte Carlo significance increases (eg lower p values) after adding the current data to previously-obtained data are listed in Table 1. (right) Comparisons between allele frequency assessments at 520,000 genomic SNPs in two subgroups of the European American nicotine dependent research participants who volunteered for inclusion in nicotine cessation trials, described previously. NDQ subjects successfully abstained from smoking for at least 6 weeks after completion of therapeutic trials using nicotine and/or mecamylamine, NDNQ subjects did not abstain for this period. The preplanned analysis of this data focused on the extent to which the nominally-positive SNPs from this comparison clustered together in genomic regions that encoded genes in comparison to chance levels, assuming independence of SNP allelic frequencies. Genes that contain at least three nominally positive SNPs and are thus nominees to contain variants that participate in the genetic underpinnings of individual differences in smoking quit success are listed in [see additional file 1].