As oxidized isoforms of DJ-1 are indicative of increased oxidative stress [86-88], moving forward, they should be explored along with total DJ-1 and other promising biomarkers, in various body fluids, especially in the saliva of PD patients [73] or those with premotor signs, thereby facilitating the development of premotor biomarkers. The gene discussed is PARK7; the disease is Parkinson disease.