The mutation of DJ-1 leads to misfolded α-syn aggregates in DA neurons of PD patients (Zondler et al., 2014); the lack of DJ-1 decreases the consumption of hydrogen peroxide and the clearance of ROS in the brain mitochondria, as well as increasing oxidative stress levels, leading to the death of DA neurons (Lopert and Patel, 2014). The gene discussed is PARK7; the disease is Parkinson disease.