Independent of the ‘infection route’, the observations from the Braak studies of sporadic PD highlight that the development of increasing degrees of Lewy pathology not only follows a predictable topographical distribution, but most importantly the predicted areas are anatomically interconnected, leading to the suggestion of a connectome hypothesis of α-synuclein propagation, similar to that described in the tau propagation field. Here, MAPT is linked to Parkinson disease.