A more recent study identified a novel LRRK2 variant (E193K) in an Italian family, and showed that fibroblasts cultured from these patients with PD had reduced LRRK2-Drp1 binding after treatment with MPP+, and this impacted mitochondrial fission (Perez Carrion et al., 2018). The gene discussed is LRRK2; the disease is Parkinson disease.