Mutations in Leucine rich repeat kinase 2 (LRRK2) that is a major regulator of both idiopathic (Nalls et al., 2014) and genetic forms of Parkinson’s Disease (PD) (Zimprich et al., 2004) cause hyperactivation of its kinase activity and are implicated in phosphorylation of Rab8a, Rab10 and Rab12 in cultured human and mouse cells, and mice (Ito et al., 2016; Steger et al., 2016; Thirstrup et al., 2017). Here, RAB8A is linked to Parkinson disease.