Importantly, the spatial location of hypometabolism differs among the different AD syndromes, conceding an opportunity to discriminate the actual phenotype: it begins in the MTL years before the onset of the disease and then spreads to the lateral parietal cortex in ADAD [51]; it is strongly correlated with Tau deposition in early-onset Alzheimer’s disease [52]; and it predominates in the MTL and medial parietal lobe in late-onset Alzheimer’s disease [53]. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.