For the family-based samples, no significant evidence of association was found for any of the four SNPs in an additive genetic model (with covariates age and sex), including the rs7916403 G risk allele (frequency of 0.52), which produced an OR of 1.13 [95% CI: 0.94 – 1.35; P = 0.19] for alcohol dependence. However, consistent with the results obtained for the case-control samples, significant evidence for an increased risk with the number of G alleles was observed for rs7916403, with an OR of 1.37 [95% CI: 1.01 – 1.85] for a full recessive model (P = 0.042). The mean theta ERO value for the G/G homozygotes is 3.85 ± 1.06 μV, again revealing an oscillatory deficit (P = 0.013), relative to the combined mean of the other two genotypes (4.04 ± 1.21 μV).
