MAPT and tauopathy: The absence of a significant species barrier is consistent with previous studies demonstrating seeding by insoluble tau from human tauopathy brains in wild-type mice (Clavaguera et al., 2013; Audouard et al., 2016; Guo et al., 2016; Narasimhan et al., 2017; Ferrer et al., 2019a, b; Vergara et al., 2019).