Prenatal smoking, genetic risk factors increase aggressive behavior in children


Researchers have found evidence of an interaction between prenatal smoking and genetic risk factors that increase aggressive behavior in children, especially in girls.

“The interesting issue is that not all children exposed to prenatal smoking will have behavioral problems. Some might, but others will not,” said Brian Boutwell, Assistant Professor at Sam Houston State University, College of Criminal Justice and senior author on the study. “One possible explanation for this is that the effect of prenatal smoke exposure depends on the presence of ‘triggering influence;’ in this case, we investigated whether genetic risk factors might act as just such a trigger.”

The study, “Prenatal Smoking and Genetic Risk: Examining the Childhood Origins of Externalizing Behavioral Problems,” was led by Melissa Petkovsek, a doctoral student at Sam Houston State, and was based on a nationally representative sample of 1,600 twins, including identical and fraternal pairs, collected during early childhood. The study found that children exposed to prenatal smoking, and who also had an increased genetic propensity for antisocial behavior, exhibited the most pronounced conduct problems during childhood. Interestingly, this gene-environment interaction was most pronounced in females.

The study demonstrates that prenatal environmental experiences may influence future behavioral problems in children, especially in combination with the presence of genetic risk factors. Ultimately, the study presented four key findings:

  • Genetic risk factors increase behavioral problems in children
  • Prenatal maternal smoking, when taken in isolation, did not appear to directly result in behavioral problems

  • The influence of genetic risk factors on behavior problems were most pronounced for children exposed to prenatal smoking

  • The interaction between genetic factors and prenatal smoking was isolated to females