PARK7 and Parkinson disease: DJ-1 can inhibit α-synuclein aggregation (Shendelman et al., 2004; Zondler et al., 2014), and immunohistology has revealed that DJ-1 is present in the halo part of Lewy bodies, which contain insoluble α-synuclein, in sporadic PD patients (Neumann et al., 2004; Jin et al., 2005).