Examining the Performance of Polygenic Risk Scores for Alzheimer Disease Within and Across Populations Using k-Fold Cross-Validation.

Alzheimer disease (AD) has a complex etiology with a strong genetic component. Despite mounting evidence that genetic risk effect sizes vary by population, most research on the genetics of AD has examined only data sets of individuals with European ancestry. In this study, we investigate the variable performance and transferability of polygenic risk scores (PRSs) by deriving a PRS from analyses of AD for various race and ethnic categories and applying this across groups using a k-fold cross-validation approach.