Similarly, tau obtained from the brain of different human tauopathies has the capacity to seed and spread in transgenic mice expressing the longest human four-repeat tau isoform (ALZ17 line) (Clavaguera et al., 2013a, b), or in transgenic mice bearing the P301S tau mutation (line PS19) (Boluda et al., 2015). The gene discussed is MAPT; the disease is tauopathy.