MAPT and tauopathy: The inoculation of brain extracts from mice or humans with tauopathy into the brain of wild-type animals induced tau pathology in recipient animals and its propagation from the site of injection along neuronal connections (Clavaguera et al., 2009, 2013; Lasagna-Reeves et al., 2012; Ahmed et al., 2014; Guo et al., 2016; Gibbons et al., 2017; Narasimhan et al., 2017; Smolek et al., 2019a,b).