Recently, mutations of the genes for mitochondrial twin CX9C proteins, CHCHD2 and CHCHD10, were identified as being linked to the pathogenesis of Parkinson’s diseases (PD) [7], amyotrophic lateral sclerosis (ALS) and frontotemporal lobe dementia (FTD) [8]. The gene discussed is CHCHD2; the disease is Parkinson disease.