These studies include the interrelation between, and co-contributions from, the two major pathologies: synucleinopathy (i.e., classic PD α-syn cortical pathology) and neutritic amyloidopathy (i.e., Alzheimer pathology) [5], and also the particular contribution of cortical burden of tau neurofibrillary tangles [35, 36]. This evidence concerns the gene MAPT and Parkinson disease.