Children from less educated parents are more prone to depression, anxiety, and ADHD, but the causal link is unclear. This study used within-family Mendelian randomization with 40,879 Norwegian children (MoBa cohort) to assess the impact of parental education on children's traits at age 8. Little evidence supported a causal effect of maternal or paternal education on children's mental health traits. However, children's own polygenic scores for educational attainment were negatively associated with these traits. The findings suggest genetic factors may explain the observed correlations more than environmental influences from parents' education. Further research is needed in populations with greater socioeconomic disparities.

Amanda M. Hughes, Fartein Ask Torvik, Elsje van Bergen, Laurie J. Hannigan, Elizabeth C. Corfield, Ole A. Andreassen, Eivind Ystrom, Helga Ask, George Davey Smith, Neil M. Davies, Alexandra Havdahl