Interaction between MAO-A genotype and maltreatment in the risk for conduct disorder: failure to confirm in adolescent patients

Am J Psychiatry. 2006 Jun;163(6):1019-25. doi: 10.1176/ajp.2006.163.6.1019.


Objective: Childhood maltreatment is a potent risk factor for subsequent aggressive and criminal behavior. A recent study suggested that the relationship between maltreatment and antisocial behavior may be moderated by a genetic vulnerability conferred by a functional polymorphism in the MAO-A gene. The authors investigated whether these findings would generalize to a clinical cohort of adolescents, examining whether there was a stronger association between maltreatment and conduct disorder severity in patients carrying the low MAO-A activity allele.

Method: Male adolescent patients (N=247) entering residential or intensive day treatment for persistent conduct and substance use problems were examined. Conduct disorder severity was indexed by a lifetime count of DSM-IV criteria obtained through structured psychiatric interviews. Maltreatment scores were derived from summing neglect and abuse events reported to have occurred before age 11.

Results: Neglect, verbal/psychological abuse, physical abuse, and sexual abuse were prevalent among patients. Although level of maltreatment and lifetime conduct disorder symptoms were significantly correlated, no genetic-environmental interaction with genotype for maltreatment was found.

Conclusion: The results of the current study do not support the hypothesis that a polymorphism in the gene encoding MAO-A contributes to the genetic risk for conduct disorder.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Age Factors
  • Child Abuse / diagnosis
  • Child Abuse / psychology
  • Child Abuse / statistics & numerical data*
  • Child Abuse, Sexual / diagnosis
  • Child Abuse, Sexual / psychology
  • Child Abuse, Sexual / statistics & numerical data
  • Child Behavior Disorders / diagnosis
  • Child Behavior Disorders / epidemiology
  • Cohort Studies
  • Comorbidity
  • Conduct Disorder / diagnosis
  • Conduct Disorder / epidemiology*
  • Conduct Disorder / genetics*
  • Diagnostic and Statistical Manual of Mental Disorders
  • Genetic Predisposition to Disease
  • Genotype
  • Humans
  • Male
  • Monoamine Oxidase / genetics*
  • Polymorphism, Genetic
  • Psychiatric Status Rating Scales
  • Reproducibility of Results
  • Risk Factors
  • Severity of Illness Index
  • Substance-Related Disorders / diagnosis
  • Substance-Related Disorders / epidemiology


  • Monoamine Oxidase