(Putz et al., 2008). Furthermore, α6 and β3 are likely to be co-regulated since they are adjacently located in the genome and co-localized to the substantia nigra, ventral tegmental area, striatum, and locus coeruleus (Gotti et al., 2006). However, in vitro studies of the α6 and β3 subunits are challenging since they are not widely expressed in cell culture lines, difficult to transfect, and difficult to separate from α4β2-containing receptors. Therefore, a focus on these two subunits in humans is one line of research that would complement limitations of lab-based studies. In previous work, we found an association between SNPs in the CHRNB3 gene and tobacco behavior in a large nationally representative adult sample (Hoft et al., 2008). It was of interest to consider whether this finding is specific to tobacco, or whether it might generalize to the other most readily available substance, alcohol. Therefore, the current study explores the possibility that variations within these genes are also associated with alcohol behaviors.
