A large number of coding changes in the LRRK2 gene have been identified but only six have strong evidence for pathogenicity in PD (Ross et al. 2011): R1441C/G, N1437H, Y1699C, G2019S and I2020T (Kalia et al. 2015; Puschmann et al. 2012; Greene et al. 2014). Here, LRRK2 is linked to Parkinson disease.