MAPT and tauopathy: Tau can aggregate acquiring different conformations, also termed strains.67–69 Inoculation of brain homogenate from different tauopathies into mice induced comparable tau inclusions to that of the exogenous brain extract, thereby stably maintaining the specific strain assembly or conformation reminiscent of the initial pathology.34,35 Eighteen tau strains have been characterized and, when inoculated in P301S mice, they trigger strain-specific intracellular pathology in specific brain regions, spreading, and toxicity.68