Genome-wide analysis of histone acetylation in the brain samples of idiopathic PD individuals showed an increase in acetylation of H3K27 similar to that of AD individuals, and prediction analysis indicates a strong link between the altered acetylation and expression of PD-associated genes (synuclein alpha (SNCA), microtubule-associated protein tau (MAPT), and parkin RBR E3 ubiquitin protein ligase (PRKN)) [179]. Here, SNCA is linked to Alzheimer disease.