LRRK2 and Parkinson disease: Recent studies on Parkinson’s disease (PD) identified a global DNA hypermethylation in monogenic leucine-rich repeat kinase 2 (LRRK2)-associated PD patients, as well as in sporadic PD patients, as another approach for diagnosing and targeting the neurodegenerative disease, in addition to already established hallmarks following the loss of midbrain dopaminergic neurons [116].