We also identified a SNP, rs2360867, located in intron 5 of SLC9A9, which remained significantly associated with errors of commission after adjustment for multiple testing. Increased errors of commission are thought to reflect impulsive behavior, although we do not see any evidence of association with hyperactive-impulsive symptoms according to the teacher or parent rating scales. Interestingly, intron 5 of SLC9A9 has been previously associated with combined type AD/HD (Brookes et al., 2006). Brookes et al. (2006) found weak evidence of association with rs2360867 and AD/HD (WHAP: P value=0.036, UNPHASED: P value=0.216).
