MAPT and early-onset autosomal dominant Alzheimer disease: These proteins are responsible for the hyperphosphorylation of tau protein fragments, leading to their aggregation and consequent formation of intracellular neurofibrillary tangles(NFTs).33Since tau protein, in association with tubulin, is essential for microtubule homeostasis,36it is reasonable to infer that interneuronal communication will be affected in the case of NFT formation, which also favors neuronal loss.37There is accumulated evidence pointing towards the use of both of this proteins (Aß and tau) as biomarkers of Alzheimer's Disease.