Brain morphometric correlates of MAOA-uVNTR polymorphism in violent behavior

Abstract Introduction Violent behavior is influenced by genetic factors, and the MAOA-uVNTR polymorphism has been associated with violent behavior, specifically the low activity variant. It has been suggested that this polymorphism impacts on grey matter concentration in structures associated with behavioral inhibition and emotion processing, however in previous imaging studies well defined violent subjects have not been explored. Objective To investigate the effect of MAOA-uVNTR polymorphism on brain structure of violent subjects. Methods The grey matter concentration of 47 adult male subjects from a community sample classified as violent or controls, was assessed through DARTEL-voxel-based morphometry technique. Results A significant genotype by behavior interaction was found in which violent-low activity allele carriers had decrease of grey matter concentration in right superior temporal pole compared to controls of the same allelic variation. Discussion This findings suggests that grey matter integrity in superior temporal pole could be a neurobiological correlate of the allelic association between MAOA-uVNTR polymorphism and violent behavior due to its implication in socio-emotional processing.