In transgenic and wild‐type mice, cell‐to‐cell propagation has been demonstrated with intracerebrally injected human brain extracts from AD, various primary tauopathies 59, α‐ synucleinopathy (PD 126 and MSA 117), and more recently also from patients with FTLD‐TDP43 79. This evidence concerns the gene TARDBP and multiple system atrophy.