MAOA and personality disorder: Genetic factors play a role in shaping the development of neurobiological markers across three domains, criminal behaviour, personality disorders, and mental health, because heterogeneity is observed within each domain due to such influence. Genetic issues arising from variations in the pathways of neurotransmitters, especially those associated with serotonin, dopamine as well as MAOA, react with environmental factors to influence the development and incidence of criminal acts, personality disorders, and mental health issues [31].