Autosomal dominant LRRK2 mutations were identified in 2008 by two groups (Paisán-Ruíz et al., 2004; Zimprich et al., 2004), with mutations in this gene now recognized as one of the most common genetic contributors to heightened risk of PD affecting different ethnic populations variably, and has also been implicated in sporadic PD (Lesage et al., 2006; Ozelius et al., 2006; Healy et al., 2008; Nalls et al., 2014). This evidence concerns the gene LRRK2 and Parkinson disease.