With the advancements in both biofluid and imaging-based biomarkers, the field has been moving towards a more biologically based definition of Alzheimer’s disease.24,56 This has recently been formulated in the National Institute of Aging-Alzheimer’s Association research framework,57 in which patients are dichotomously classified along three dimensions: amyloid (A), tau (T) and neurodegeneration (N).58 Parallel to neuropathological definitions of Alzheimer’s disease, one must have the presence of both amyloid and tau biomarkers (A+, T+) to be classified as having Alzheimer’s disease. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.