Ca2+ signaling is centrally involved in synaptic transmission, plasticity, and tau phosphorylation, and thus can generate a self-sustaining pathogenic cycle, as seen in chronic neurodegenerative disorders such as Alzheimer’s disease (Stutzmann, 2007; Chakroborty et al., 2009, 2012, 2019). This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.