LRRK2 and Parkinson disease: Expression of the most common PD-associated LRRK2 mutation, G2019S (Kachergus et al., 2005), may uncouple mitochondrial oxidative phosphorylation (Mortiboys et al., 2010; Papkovskaia et al., 2012) and increase intracellular ROS production in vitro (Pereira et al., 2014).