Finally, we combined the CADD and GADD samples to determine if there was an association signal present in these genes. Both SNPs tested in the combined non-Hispanic EA CADD and GADD sample showed nominal associations with DSM-IV ND symptoms (all p-values < 0.05; Table 6). When taken into account that 2 SNPs were tested, the significance level associated with rs1044396 exceed the min –p threshold (p < 0.05). In the combined EA and Hispanic population both CHRNA4 SNPs were no longer significantly associated with ND.
