In brief, we observe higher frequencies of individuals carrying APOE:rs449647-T, 19q13.31:rs10423769-A, APP:rs466433-G, or APP:rs364048-C protective variant alleles alongside either one or two copies of APOE ε4 among African and African Admixed ancestries compared to Europeans in AD, related dementias, and controls. Here, APP is linked to Alzheimer disease.