Peer Victimization and DRD4 Genotype Influence Problem Behaviors in Young Children

Abstract

Decades of research supports the presence of significant genetic influences on children's internalizing (emotional), externalizing (acting out), and social difficulties, including victimization. Additionally, being victimized has been shown to relate to further behavioral problems. The current study assessed the nature of the gene-environment relationships between the DRD4 gene, peer victimization, and externalizing and internalizing difficulties in 6-to 10-year-old children. 174 children (56% girls; 88.6% Caucasian, 3.4% African American, 8% mixed race or Mayan) and their parents were administered victimization and problem behavior questionnaires, and DRD4 was genotyped for the children. An interaction between genes (DRD4) and environment (victimization) was significant and supported the differential susceptibility model for verbal victimization and child-reported externalizing behaviors. Children with the DRD4 7-repeat allele were differentially responsive to the verbal victimization environment, such that those experiencing little to no victimization reported significantly lower levels of externalizing behaviors, but if they experienced high amounts of victimization, they reported the highest levels of externalizing behaviors. Thus, consideration of how genes and environment affect children's experiences of victimization prior to adolescence is essential for understanding the trajectory of both externalizing and internalizing behaviors during adolescent development.

Chronic Stressors and Adolescents’ Externalizing Problems: Genetic Moderation by Dopamine Receptor D4. The TRAILS Study

“…Externalizing problems correlated significantly ( p < 0.001) with internalizing problems, at both T2 ( r = 0.52, parent-report, and r = 0.38, self-report) and T3 ( r = 0.54, parent-report, and r = 0.32, self-report). Since internalizing problems have no theoretical and empirical relevance in relation to DRD4 –7R (e.g., Bakermans-Kranenburg and Van IJzendoorn 2006 ; DiLalla et al 2015 ), potential interaction effects of DRD4 –7R and stressors in predicting externalizing problems may be weakened by the presence of co-occurring internalizing problems. Therefore, we focused on externalizing problems adjusted for co-occurring internalizing problems (EXTadj).…”

“…At 36 months, however, 7R carriers showed a similar response, but noncarriers showed the opposite (i.e., higher sensitivity predicted higher externalizing levels), rather than no response. One study in middle childhood showed higher sensitivity for better and for worse in 7R carriers compared to noncarriers, to verbal but not physical peer victimization and with respect to self-reported but not parent-reported externalizing problems (DiLalla et al 2015 ). Thus, these prior findings do not consistently support the Differential Susceptibility model.…”

Respiratory sinus arrhythmia in the fourth decade of life depends on birth weight and the DRD4 gene: Implications for understanding the development of emotion regulation

“…One gene that has been identified as a potentially important differential susceptibility polymorphism for the development of neurophysiological, neurological, psychiatric, and developmental problems is the exon III 7‐repeat (long) allele of the dopamine D4 receptor gene(DRD4) (Belsky, ). In past studies utilizing a gene by environment interaction framework, this allele has been linked with increased attentional and externalizing problems among children who were exposed to adverse exposures such as sub‐optimal parenting (Bakermans‐Kranenburg & Van Ijzendoorn, ; Bakermans‐Kranenburg, Van IJzendoorn, Pijlman, Mesman, & Juffer, ; Sheese, Voelker, Rothbart, & Posner, ) or peer‐victimization (DiLalla, Bersted, & John, ), while conferring decreased levels of attentional problems in children exposed to more nurturing environments (Bakermans‐Kranenburg & Van Ijzendoorn, ). The DRD4 long allele also appears to confer an advantage in terms of reducing substance use problems in youth participating in substance treatment programs, while being linked to worse substance use in adolescents not in treatment (Beach, Brody, Lei, & Philibert, ).…”

ADHD symptoms across adolescence: the role of the family and school climate and the DRD4 and 5-HTTLPR genotype

“…In relation to the school environment, genetic moderation studies with the DRD4 genotype have examined the influence of peers and teachers in promoting positive development. For example, children with the DRD4 7-repeat allele who experienced little to no peer victimization had lower levels of externalizing behaviors compared to when they experienced high amounts of peer victimization [37]. However, in a previous TRacking Adolescents' Individual Lives Survey (TRAILS) study, in relation to delinquency, DRD4 7-repeat allele carriers were less sensitive to the effects of both peer victimization and social well-being [38].…”