It is noteworthy that there was no evidence for association with “dizziness” and the CHRNA5/A3/B4 gene cluster on chromosome 15, which has been repeatedly associated with smoking behaviors, including age of initiation (Schlaepfer et al., 2008a; Weiss et al., 2008), “pleasurable buzz” during early experimentation (Sherva et al., 2008), cigarettes per day (Berrettini et al., 2008; Thorgeirsson et al., 2008), nicotine dependence (Bierut et al., 2007; Saccone et al., 2007), and lung cancer (Amos et al., 2008; Hung et al., 2008). At least two independent loci in this region have been identified for association with nicotine dependence (Bierut et al., 2008; Saccone et al., in press), with evidence for functional relevance of a non-synonomous SNP rs16969968 in the α5 subunit (Bierut et al., 2008). The CHRNA5/A3/B4 cluster is associated with nicotine dependence in this sample (see Saccone et al., in press, and Supplementary Table 1), but the p-value for association between “dizziness” and rs16969968 is 0.40. Nor did we find evidence for association between “pleasurable buzz” and rs16969968 (p=0.43, data not shown). This lack of association highlights the challenge of
