Education-related polygenic scores show different associations with youth mental health in parent-offspring trios

Abstract Educational attainment and mental health are associated from childhood, but less is known about how this association is reflected within families, where children’s genetic variation is correlated with both parental genotypes and family environments. We examine whether associations involving children’s own and parental polygenic scores differ for cognitive and non-cognitive genetic components of educational attainment. These scores aggregate common DNA variants using weights from genome-wide association studies. We analyse 3,223 mother-father-child trios from the UK Millennium Cohort Study using structural equation models that jointly estimate associations involving children’s own and parental polygenic scores. Here we show that cognitive and non-cognitive education-related polygenic scores are associated with externalising behaviour, including hyperactivity and conduct problems, and internalising behaviour, including anxiety and low mood, across childhood and adolescence. Associations are generally larger in magnitude for externalising than internalising behaviour, with clearer component-specific differences for externalising behaviour. These findings highlight the heterogeneity in education-related polygenic score associations with youth mental health within families.