It should be noted that in CBD and PSP patients, hyperphosphorylated tau is found both in neurons and in glial cells, and although the autophagy-lysosomal pathway has been demonstrated to be the main degradative pathway of tau in neurons, other mechanisms (including the ubiquitin-proteasome system) may be involved in degradation of tau in other cell types such as glia [32, 67, 68]. This evidence concerns the gene MAPT and red-green color blindness.