Gain-of-function toxicity of tau has been implicated in the pathogenesis of AD, which is predominantly characterized by the presence of pathological protein aggregates such as tau aggregates and amyloid-β (Aβ) containing senile plaques (Mitchell et al., 2002; Maeda et al., 2006; Johnson et al., 2016; Schöll et al., 2016). The gene discussed is MAPT; the disease is Alzheimer disease.