LRRK2 is the most frequently mutated gene in familial Parkinson’s disease (PD) (Paisán-Ruíz et al., 2004; Zimprich et al., 2004), and has also been identified as a risk locus for the sporadic form of the disease (Nalls et al., 2014). The gene discussed is LRRK2; the disease is Parkinson disease.