VCP and amyotrophic lateral sclerosis: For instance, mutations in VCP account for about 2% of familial ALS and R155H/+ VCP knock-in mice show signs of motor damage due to muscle denervation and degeneration accompanied by extensive accumulation of abnormal mitochondria in the inter-myofibrillar space; in this model slow motor neuron loss is accompanied by TDP-43 accumulation and extensive aggregation of mitochondria (Yin et al., 2012; Nalbandian et al., 2013).