LRRK2 and Parkinson disease: Studies using hiPSCs generated from PD patients with LRRK2 mutations have described the appearance of disease-specific phenotypes in hiPSC derived neurons, including impaired axonal outgrowth, increased susceptibility to oxidative stress (Nguyen et al., 2011), pathogenic activation of the unfolded protein response (Heman-Ackah et al., 2016) and deficient autophagic vacuole clearance (Sánchez-Danés et al., 2012).