Second, overexpressing VCP mutants, VCP-R155H or VCP-A232E, results in defects in autophagy by impairing ubiquitin-containing autophagosome maturation, and leads to the accumulation of autophagosomes, which contribute to the pathogenesis of IBMPFD [65]. Here, VCP is linked to inclusion body myopathy with Paget disease of bone and frontotemporal dementia.