Although plasma NFL overlaps between the diagnostic groups, the accuracy of plasma NFL for AD dementia vs controls is close to established CSF AD biomarkers and much higher than for plasma tau (AUROC, 0.87 vs 0.78 when adjusted for demographics and APOE ε4; AUROC, 0.79 vs 0.64 when adjusted only for demographics). This evidence concerns the gene MAPT and Alzheimer disease.