LRRK2 and Parkinson disease: Although LRRK2 pathogenic mutations are linked to dopaminergic cell death, there is also evidence suggesting that LRRK2-Wt overexpression upregulates α-syn levels, thereby influencing the pathological output of LRRK2-related PD (Lin et al., 2009; Carballo-Carbajal et al., 2010).