The addition of tau assemblies, but not monomer, resulted in dose‐dependent accumulation of intracellular tau species that were stained by the antibody AT8, specific for tau phosphorylated at S202/T205, and anti‐pS422, epitopes that are present in hyperphosphorylated tau inclusions in AD brains (Figure 1C, Figure S1c). The gene discussed is MAPT; the disease is Alzheimer disease.