LRRK2 and Parkinson disease: It is associated with PD, as mutations in the LRRK2 gene are a known genetic cause of inherited forms of the disease and genetic risk of sporadic PD (Paisan-Ruiz et al. 2004; Zimprich et al. 2004; Satake et al. 2009; Simón-Sánchez et al. 2009).