In recent years, several causative genes of PD have been identified, including α-synuclein (SNCA), parkin (PARK2), UCHL-1 (PARK5), PINK1 (PARK6), DJ-1 (PARK7), LRRK2 (PARK8) and ATP13A2 (PARK9) [6], [7]. Here, UCHL1 is linked to Parkinson disease.