Point mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most frequent cause of familial, autosomal-dominant Parkinson’s disease (PD; Brice, 2005; Di Fonzo et al., 2006; Lesage et al., 2006; Ozelius et al., 2006), and sequence variations in LRRK2 are known to modify PD risk, indicating that it also plays a role in the most common sporadic form of the disease (Gilks et al., 2005; Nalls et al., 2014). The gene discussed is LRRK2; the disease is Parkinson disease.