Numerous studies have demonstrated that the intracerebral inoculation of brain tissue from individuals with AD and different tauopathies, examples of which are; progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and argyrophilic grain disease (AGD) (Figure 1), can induce the formation of tau aggregates in both tau-transgenic mice and in wild-type mice [163,164]. This evidence concerns the gene MAPT and argyrophilic grain disease.