Expression of mutant VCP leads to a multisystem inherited pleiotropic disorder that can affect muscle, bone and the nervous system, now referred to as multisystem proteinopathy (MSP), but previously referred to by the acronym IBMPFD (inclusion body myopathy (IBM) with Paget’s disease of bone (PDB) and FTD [7, 8]. The gene discussed is VCP; the disease is inclusion body myositis.