BackgroundAntisocial personality disorder (ASPD) is characterised by elevated
impulsive aggression and increased risk for criminal behaviour and
incarceration. Deficient activity of the monoamine oxidase A
(MAOA) gene is suggested to contribute to
serotonergic system dysregulation strongly associated with impulsive
aggression and antisocial criminality.AimsTo elucidate the role of epigenetic processes in altered
MAOA expression and serotonin regulation in a
population of incarcerated offenders with ASPD compared with a healthy
non-incarcerated control population.MethodParticipants were 86 incarcerated participants with ASPD and 73 healthy
controls. MAOA promoter methylation was compared between
case and control groups. We explored the functional impact of
MAOA promoter methylation on gene expression
in vitro and blood 5-HT levels in a subset of the
case group.ResultsResults suggest that MAOA promoter hypermethylation is
associated with ASPD and may contribute to downregulation of
MAOA gene expression, as indicated by functional
assays in vitro, and regression analysis with
whole-blood serotonin levels in offenders with ASPD.ConclusionsThese results are consistent with prior literature suggesting
MAOA and serotonergic dysregulation in antisocial
populations. Our results offer the first evidence suggesting epigenetic
mechanisms may contribute to MAOA dysregulation in
antisocial offenders.