Tau is a neuronal MAP enriched in the axon that becomes hyperphosphorylated, accumulates in the somato-dendritic compartment and self-aggregates into insoluble filaments called paired helical filaments (PHFs) forming the neurofibrillary tangles (NFTs) in Alzheimer’s disease (AD) (Ludin and Matus, 1993; Mandell & Banker, 1996; Lee et al., 2001; Cairns et al., 2007; Iqbal et al., 2016). The gene discussed is MAPT; the disease is Alzheimer disease.