ATAD1 and inclusion body myopathy with Paget disease of bone and frontotemporal dementia: More than 45 missense mutations in VCP have been identified in multiple neurodegenerative diseases, including inclusion body myopathy associated with Paget disease of the bone and frontotemporal dementia (IBMPFD; also referred to as multisystem proteinopathy MSP1), amyotrophic lateral sclerosis (15), and tauopathy (16, 17), indicating the importance of VCP function for neuronal health.