Accumulation of pathogenic tau can disrupt neural connectivity and synaptic function, eventually leading to neural cell death and atrophy of several brain regions characteristic of diseases such as Alzheimer’s disease (AD), Corticobasal degeneration (CBD), Frontotemporal degeneration/dementia (FTD), Lewy Body disease (LBD) and Parkinson’s disease (PD). This evidence concerns the gene MAPT and Parkinson disease.