The link of LRRK2 to sporadic PD has also been suggested by a set of genome-wide association studies (GWAS) where common variants around LRRK2 gene have been identified as a risk factor of PD (Satake et al., 2009; Simón-Sánchez et al., 2009; Lill et al., 2012). Here, LRRK2 is linked to Parkinson disease.