The discovery of multiple mutations in the mitochondrial quality-control protein PTEN-induced putative kinase 1 (PINK1), which are responsible for the autosomal recessive familial PD [121], and, given the implication of PINK1 in mitochondrial dynamics [122,123], the conclusion is that mitochondrial integrity in PD pathogenesis is of central importance. This evidence concerns the gene PINK1 and Parkinson disease.