Human tau has been overexpressed in many mouse models which have been shown to reproduce the cognitive impairment found in AD (Berger et al., 2007; Eckermann et al., 2007; Lasagna-Reeves et al., 2011; Roberson et al., 2011; Sydow et al., 2011; Webster et al., 2014) and neuronal death.1 The gene discussed is MAPT; the disease is Alzheimer disease.