We found that current smokers with the SLC6A3 10r/10r genotype were more likely to have low nicotine dependence, based on HSI analysis, although the genotypic differences between current and former smokers were not significant for any of the SLC6A3, ANKK1/DRD2, and CYP2A6 polymorphisms tested. This evidence concerns the gene DRD2 and nicotine dependence.