LRRK2 and Parkinson disease: Relevant studies (Di Fonzo et al., 2005; Gilks et al., 2005; Mata et al., 2005; Nichols et al., 2005) have found that there are many mutation sites in the LRRK2 gene, resulting in approximately 100 LRRK2 variants, many of which are related to PD, and the G2019S, R1441G, R1441C, R1441H, Y1699C, I2020T, and N1437H variants were confirmed to be pathogenic.