In the familial Parkinson's disease, loss-of-function mutations in Parkin and PINK1 caused accumulation of dysfunctional mitochondria and leaded to nigral neurodegeneration and early-onset Parkinson's disease, which indicates PINK1 and Parkin as key mediators of mitochondrial homeostasis and mitophagy 75, 76. The gene discussed is PINK1; the disease is Parkinson disease.