Although many neuronal populations including midbrain dopamine and hippocampal neurons express LRRK2, high levels of expression in the basal ganglia suggest a particularly important role for striatal LRRK2 in PD (Melrose et al., 2006; Higashi et al., 2007; Westerlund et al., 2008; Giesert et al., 2013). Here, LRRK2 is linked to Parkinson disease.