Of interest, a very recent longitudinal study conducted on elderly subjects enrolled in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) reported that increased plasma levels of p-tau paralleled Aβ pathology in the brain [50], thus suggesting that amyloid plaque deposition is linked to dysregulated tau metabolism, with subsequent release of the soluble p-tau181 in circulation [50]. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.