W81. IMPACT OF EARLY ENVIRONMENTAL RISK ON ASSOCIATIONS BETWEEN GENETIC LIABILITY AND TRAJECTORIES OF EXTERNALIZING PROBLEMS IN EARLY ADOLESCENCE

Externalizing disorders (e.g., Conduct Disorder) emerge during childhood and adolescence and are thought to share common temperamental and behavioral precursors (e.g., impulsivity), reflecting one or more common etiological processes. Despite a strong genetic influence, twin studies have also found that differential exposure to environmental risk factors (e.g., poverty, trauma, discrimination) during early development can impact the emergence of these behaviors and potentially mitigate or exacerbate genetic liability. The current analyses examined how the association between genetic liability associated with externalizing behaviors, measured via a polygenic score (EXT PGS) and the development of externalizing problems during emerging adolescence are moderated (i.e., influenced in strength or direction) by exposure to environmental risk across multiple domains. The analytic sample of N = 10,634 was from the Adolescent Brain Cognitive Development Study (release 5.1; 58.2% male, 5 years of longitudinal data from ages 9-14). We examined the associations between the development of externalizing behaviors, measured via parent (Child Behavior Checklist; CBCL) and youth-report (Brief Problem Monitor; BPM) longitudinally from ages 9-14, EXT PGS, exposure to environmental risk, and the moderating effect of environmental risk on EXT PGS. Environmental risk was measured using a factor score comprised of indices of pre/perinatal (e.g., birth complications), household (e.g., poverty), neighborhood (e.g., lead exposure), and state level (e.g., legality of cannabis) risk as well as experiences of discrimination (e.g., related to gender). We evaluated associations with polygenic risk associated with externalizing (EXT PGS), exposure to environmental risk, and tested whether environmental risk moderated the relationship between EXT PGS and externalizing trajectories. All analyses were run in Mplus8. The EXT PGS was significantly associated with externalizing problems at baseline and with change in youth-report of externalizing problems over time. General environmental risk was significantly associated with both the intercept and slope factors. The association between the EXT PGS and the intercept (parent and youth-report) was significantly moderated by the general environmental risk factor. Also, the association between the EXT PGS and the development of externalizing behavior (parent-report slope) was significantly moderated by state-level risk factors. These results demonstrate that exposure to environmental risk amplified the association between genetic liability toward externalizing and externalizing behavior at age 9. In addition, state-level risk factors, which largely reflect the legality of medicinal and recreational cannabis where the youth reside, may amplify the association between the EXT PGS and the development of externalizing behavior.