DRD4 VNTR >7 repeat individuals showed greater blood-oxygen-level dependent (BOLD) signal response to alcohol cues, versus control cues (i.e., litchi juice), in regions such as the orbitofrontal cortex, anterior cingulate gyrus, and striatum, as compared to individuals with <7 repeats, but only at the pre-priming level of analysis. In contrast, G-allele carriers of the OPRM1 gene exhibited greater BOLD signal response to alcohol versus control cues in mesocorticolimbic areas before and after alcohol priming (target BrAC=0.03g/dl), as compared to A-allele homozygotes, suggesting insensitivity to the priming dose in G-allele carriers.
