There was a significant 2-way interaction for time × DAT1 genotype (F7, 856 = 2.17, p = 0.035) on DEQ VAS negative scores. Across time points, the DAT1 A9 carriers had higher DEQ VAS negative scores when compared to the A10 carriers, independent of OPRM1 genotype. A significant 3-way interaction for time × DAT1 gentype × OPRM1 genotype (F7, 856 = 2.31, p = 0.025) indicated an epistatic interaction; carriers of both DAT1 A9 and OPRM1 *G alleles had the highest DEQ VAS negative scores across time points (Figure 3).
