Background: Maternal distress during pregnancy has been linked to aggressive behavior in offspring. This effect has been interpreted in terms of 'fetal programming'. The 7-repeat (7r) allele of a VNTR polymorphism in exon III of the human dopamine receptor D4 (DRD4) has consistently been associated with externalizing behavior problems, especially in the presence of adverse environmental factors. So far, it is not known whether the DRD4 genotype moderates the effect of prenatal maternal stress on the development of childhood antisocial behavior.
Methods: As part of an ongoing epidemiological cohort study, prenatal maternal stress was assessed using self-report 3 months following child birth. When children were 8, 11, and 15 years old, mothers rated their children's externalizing behavior, and diagnoses of conduct disorder and/or oppositional defiant disorder (CD/ODD) according to DSM-IV were obtained. In a sample of N = 308 participants, the effects of the DRD4 genotype, prenatal maternal stress, and the interaction thereof on antisocial outcome were tested.
Results: Under conditions of elevated prenatal maternal stress, children carrying one or two DRD4 7r alleles were at increased risk of a diagnosis of CD/ODD. Moreover, homozygous carriers of the DRD4 7r allele displayed more externalizing behavior following exposure to higher levels of prenatal maternal stress, while homozygous carriers of the DRD4 4r allele turned out to be insensitive to the effects of prenatal stress.
Conclusions: This study is the first to report a gene-environment interaction related to DRD4 and prenatal maternal stress using data from a prospective study, which extends earlier findings on the impact of prenatal maternal stress with respect to childhood antisocial behavior.
Keywords: DRD4; Prenatal stress; antisocial; conduct disorder; gene-environment interaction.
© 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.