Variability in prior research findings is best understood by inadequate power to detect G×E associations, due to the low base rates of maltreatment and antisocial symptoms in most of the investigations that failed to replicate this association. Our investigation is consistent with the findings of Caspi et al. (1) and suggests that problems in aggression in maltreated children are moderated by MAOA genotyps—but only up to moderate levels of trauma exposure.
