MAOA-VNTR polymorphism modulates context-dependent dopamine release and aggressive behavior in males

A recent [F-18]FDOPA-PET study reports negative correlations between dopamine synthesis rates and aggressive behavior. Since dopamine is among the substrates for monoamine oxidase A (MAOA), this investigation examines whether functional allelic variants of the MAOA tandem repeat (VNTR) promotor polymorphism, which is known to modulate aggressive behavior, influences dopamine release and aggression in response to violent visual stimuli. We selected from a genetic prescreening sample, strictly case-matched groups of 2 x 12 healthy male subjects with VNTRs predictive of high (MAOA-High) and low (MAOA-Low) MAOA expression. Subjects underwent pairs of PET sessions (dopamine D-2/3 ligand [F-18]DM…