PARK7 and Parkinson disease: Noteworthily, compared with healthy controls, the expression of these proteins and their associated factors are downregulated in PD patients.138 DJ‐1 can also directly interact with α‐Syn, and DJ‐1 mutation associated with PD can induce the accumulation of misfolded α‐Syn in dopaminergic neurons, whereas the upregulation of DJ‐1 can decrease the dimerization of α‐Syn.139