LRRK2 and Parkinson disease: Furthermore, PD-related mutations in Roco4 revealed correlating decreases in GTPase activity and increasing kinase activity except for L1180T (LRRK2 I2020T), which shows reduced kinase activity like its LRRK2 counterpart (Jaleel et al., 2007; Ohta et al., 2010; Kortholt et al., 2012).