For plotting, we generated residualized expression for BAs and non-Hispanic WAs for the caudate nucleus (n = 233), dentate gyrus (n = 85), DLPFC (n = 204) and hippocampus (n = 236). After the main effect analysis, we generated covariates and normalized expression for this multi-ancestry population. With this, we applied lmFit from limma to normalize expression and covariates, excluding the variable of interest (global ancestry). Subsequently, we applied the residuals function in R (v.4.0.3) to regress out the covariates from the normalized expression.
