[11]. Thus, the minor allele at this SNP results in a significant functional change in the behavior of this ion channel, causing more nicotine to be needed in individuals with the minor allele to produce the same effect. Additionally, SNPs within the chromosome 15 and chromosome 8 regions have been associated with alocohol and cocaine dependence in addition to their associations with smoking related traits [15–17]. Although the underlying functional mechanism underlying the associations at the nicotinic receptors on chromosome 8 is not known, there is nevertheless a genome-wide significant signal with the LD bin [18].
