Familial cases of PD are linked with mutations of various genes including α-synuclein, Phosphatase and tensin homolog (PTEN)-induced kinase 1 (PINK1), Parkin 7 (PARK7), Parkin 2 (PARK2), and leucine-rich repeat kinase 2 (LRRK2) genes [148,150]. Here, PINK1 is linked to Parkinson disease.