Recent genome wide association study (GWAS) and meta-analysis results introduced Rit2 as a novel susceptibility locus, in association with decreased Rin expression in the substantia nigra pars compacta (SNc) of PD patients (Bossers et al., 2009; Latourelle et al., 2012; Pankratz et al., 2012). Here, RIT2 is linked to Parkinson disease.