There are over 75 substitutions have been found in LRRK2, and seven missense mutations (G2019S, I2020T, N1437H, R1441G/C/H and Y1699C) are pathogenic, all of which are concentrated in the central catalytic domains, suggesting an essential role of GTPase and kinase domains in the PD pathogenesis [40, 41]. The gene discussed is LRRK2; the disease is Parkinson disease.