MAPT and early-onset autosomal dominant Alzheimer disease: AT8 phosphorylation is the standard immunostaining utilized for the assessment of neurofibrillary tangle (NFT) formation and tau aggregation for Braak stage scoring and Alzheimer’s Disease progressions, with a very strong correlation with cognitive decline in preclinical Alzheimer’s Disease (Braak et al., 2006; Huber et al., 2018).