In both a subset of the UK Biobank (N: 3,722), and in 60 representative participants from COGA’s adolescent and young adult offspring on whom MRI data were available52 (Supplemental Table 1), we examined if genome-wide significant regions were also associated with posterior corpus callosum volume. Genetic association with posterior corpus callosum volume was tested using linear regression, adjusted for gender, age, total brain volume, PCs 1-3, and genotype array.
