Intergenerational transmission of polygenic predisposition for neuropsychiatric traits on emotional and behavioural difficulties in childhood

Abstract Childhood emotional and behavioural difficulties frequently co-occur and often precede diagnosed neuropsychiatric conditions. Delineating shared and specific risk factors for emotional and behavioural difficulties early in life is therefore essential for prevention strategies. Here, we focus on how a set of key parental risk factors shape their offspring’s behavioural and emotional symptoms. Leveraging data from 14,959 genotyped family trios from the Norwegian Mother, Father and Child Cohort Study (MoBa), we model symptom level data into general and specific domains. We then investigate the direct (genetically transmitted) and indirect (environmentally mediated) contributions of polygenic risk for neuropsychiatric and related traits to general and specific domains. We observe evidence consistent with an environmental route to general symptomatology beyond genetic transmission, while also demonstrating domain-specific direct and indirect genetic contributions. Our findings pave the way for a better identification of early risk pathways that can be targeted in preventive interventions aiming to interrupt the intergenerational cycle of risk transmission.