Mutations within the LRRK2 gene have been shown to segregate with PD in large families.(Cookson, 2010) Additionally, common variants at the LRRK2 locus have been linked to sporadic PD through GWAS.(Simon-Sanchez et al., 2009; Nalls et al., 2019a) The LRRK2 locus is therefore described a pleomorphic risk locus, containing both rare and common disease-linked variants.(Singleton and Hardy, 2011) Importantly, PD arising from LRRK2 mutations is indistinguishable from sporadic PD in terms of age of onset and clinical manifestation.(Kalia et al., 2015; Kett and Dauer, 2012). This evidence concerns the gene LRRK2 and Parkinson disease.