52.75±11.25 (TT)]. It is worth noting that rs1046706 was also nominally associated with hyperactive-impulsive (P= 0.001), inattentive (P=0.021), and total symptom scores (P=0.003) according to the CPRS, inattentive scores (P=0.007) according to the CTRS and the CPT measure, hit reaction time (P=0.002) (Table 4). In addition, it does not appear that rs1046706 is in high linkage disequilibrium (LD) with other typed SNPs in our population or any known SNPs in the HapMap Caucasian population (Collins et al., 1998). The second significant SLC9A9 SNP, rs2360867, is intronic and remained associated (FDR q value <0.05) with the CPT measure, errors of commission [48.15±12.53 (TT), 50.56±10.65 (CT), 52.52±10.48 (CC)]. This intronic SNP is in high LD with other known SNPs in the HapMap Caucasian population. Of note, the 3′UTR SNP, rs1046706, and the intronic SNP, rs2360867, are in minimal LD (r2=0.001) in our study population.
