This is underscored by (i) the close correlation of Tau pathology with the progression of symptoms and (ii) the existence of a family of Tauopathies which are neurodegenerative disorders characterized by Tau aggregation spatiotemporally correlating with brain dysfunction and associated symptoms, as well as, most importantly, (iii) the identification of mutations in Tau causally linked to Tauopathies, demonstrating a causal executive role of Tau in Tauopathies. The gene discussed is MAPT; the disease is tauopathy.