LRRK2 and Parkinson disease: Moreover, the sporadic form of PD has been shown to have several variations in these genes, including SNCA, LRRK2, PINK1, GBA, and PRKN, which encode α-syn, leucine rich repeat kinase 2, PTEN-induced kinase 1 (PINK1), glucocerebrosidase, also known as lysosomal acid glucosylceramidase, and E3 ubiquitin-protein ligase parkin, respectively.