PD cases are mainly sporadic, only 10–15% of cases are caused by mutations in a variety of genes including SNCA/PARK1 (encoding α-synuclein (α-SYN)), Parkin (PRKN), Parkinson’s disease protein 9 (PARK9/ATP13A2), Parkinson’s disease protein 7 (PARK7/DJ1), leucine-rich repeat kinase 2 (LRRK2), PTEN-induced putative kinase 1 (PINK1) and among other genes [90]. Here, SNCA is linked to Parkinson disease.