Mutations in p97 cause IBMPFD, a rare multisystem degenerative human disorder that afflicts skeletal muscle, bone and brain.59,60 One-third of IBMPFD patients will develop FTD and approximately 10% display features of ALS.4,9,60 Currently, there is no cure for IBMPFD patients. This evidence concerns the gene VCP and inclusion body myopathy with Paget disease of bone and frontotemporal dementia.