In the field of mitochondria and PD, frequently occurring keywords included oxidative stress (1,188 times), alpha-synuclein (677 times), neurodegeneration (520 times), apoptosis (436 times), pink1 (403 times), mitophagy (390 times), autophagy (352 times), and mitochondrial dysfunction (361 times) (Figure 6A). The gene discussed is SNCA; the disease is Parkinson disease.