Externalizing Disorders: Genetics or Prenatal Alcohol Exposure?

Externalizing disorders such as attention deficit hyperactivity disorder (ADHD), conduct disorder (CD), and oppositional defiant disorder (ODD) have a high prevalence rate in both children of alcoholics and in those with prenatal alcohol exposure (PAE). These disorders are also predictors of alcohol dependence (alcdep), heritable, and share an underlying genetic liability with alcdep. Furthermore, a mother who drinks while pregnant is likely to be alcohol dependent (AD), and vice-versa. This study incorporated these factors into one model, including as well as a measure of broad genetic risk for ADHD and alcdep to test for the contributions of these effects simultaneously. An independent sample was used to confirm the results for PAE and broad genetic risk. The hypothesis is that PAE will increase the risk to ADHD but not to CD or ODD.