PSMA2 and Parkinson disease: Previous gene expression studies have shown that the expression of several oxidative stress- or inflammation-related genes such as heat-shock protein 70-interacting protein (ST13), proteasome 20S subunit alpha 2 (PSMA2), aldehyde dehydrogenase 1 family member A1 (ALDH1A1), BCL11 transcription factor B (BCL11B), nuclear-encoded mitochondrial gene (LRPPRC), interleukin 1 beta (IL-1β) and complement receptor 1 (CR1) was altered in the peripheral blood of PD patients compared to the healthy controls [27,28,29,30,31,32,33].