Most mental health workers acknowledge that behavior problems are shaped by both environmental and genetic factors. Leve et al. (2009) tested the hypothesis that a particular kind of environmental input-structured parenting-would have different effects on children at high vs. low genetic risk for psychopathology. They did this by studying adopted children whose birth parents had completed questionnaires regarding their own substance use, antisocial behavior, depression, and anxiety. Scores for these variables were standardized and averaged to produce global measures of psychopathology for birth mothers of 290 children and birth fathers of 95 of the children. As the children were adopted at a mean age of 3 days, they experienced little environmental input from their birth parents. When the children were 18 months old, each adoptive mother-child dyad was videoed in a standardized clean-up task. The videos were then rated for the degree to which mothers structured their child’s behavior.
Mothers also completed the CBCL/1½-5. A striking interaction was found between scores for birth parents’ psychopathology and scores for adoptive mothers’ structured parenting: The highest 18-month CBCL Total Problems scores were found for children whose birth parents (analyzed separately for birth mothers and fathers) obtained high psychopathology scores and whose adoptive mothers obtained low scores for structured parenting. By contrast, low CBCL Total Problems scores were found for children whose birth parents obtained high psychopathology scores and whose adoptive mothers obtained high scores for structured parenting. In other words, structured parenting by adoptive mothers appeared to strongly counteract genetic risks associated with birth parents’ psychopathology. For children whose birth parents obtained low scores for psychopathology, the opposite relation was found between CBCL Total Problems scores and adoptive mothers’ structured parenting: CBCL Total Problems scores were significantly higher for children whose adoptive mothers were rated high on structured parenting than for children whose mothers were rated low on structured parenting.
Structured parenting thus appeared to increase problems among children at low genetic risk for psychopathology, whereas structured parenting decreased problems among high-risk children. Leve et al. concluded that the interacting effects of genetic risk and structured parenting reflected different pathways toward low vs. high problems at age 18 months: Both genetic risk and structured parenting may thus affect problem levels, but the effects of genetic risk may be modified by structured parenting and vice versa.
Reference: Leve, L.D., Harold, G.T., Ge, X., Neiderhiser, J.M., Shaw, D., Scaramella, L.V., & Reiss, D. (2009). Structured parenting of toddlers at high versus low genetic risk: Two pathways to child problems. Journal of the American Academy of Child and Adolescent Psychiatry, 48, 1102-1109.