CCNF and amyotrophic lateral sclerosis: Mutations in VCP have been described in ALS, FTD and inclusion body myopathy with Paget’s disease of bone and FTD (IBMPFD) which is an adult onset disorder characterized by muscle weakness, early onset PDB (see section “Cyclin F (CCNF)”) and FTD, though episodic memory is preserved (Kimonis, 1993).