While the etiology of Alzheimer’s disease (AD) has long been associated with the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tau tangles [1], only within the past couple decades have imaging substrates been developed to identify deposition of these AD biomarkers in vivo using positron emission tomography (PET). Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.