In CHRNA4, rs2236196 shows association in European-Americans (OR = 1.30 (1.12-1.50) p = 0.0004) and has previously been associated with smoking in independent European-descent samples (Breitling et al., 2009, Hutchison et al., 2007) and a sample of African-American women (Li et al., 2005). However, neither rs2236196 nor other tested CHRNA4 SNPs show consistent evidence in both European-Americans and African-Americans (OR=1.04 (0.83-1.30), p = 0.73 in African-Americans). The one SNP with a trend towards association in AAs, rs2229959, has odds ratios in opposite directions in the two groups (OR = 0.82 (0.66-1.02) in AAs; OR = 1.33 (1.09-1.62) in EAs).
