A further, far less common, neuropathological link between ALS and FTD is represented by FUS pathology, occurring in rare instances of both diseases; however, notably, whereas cases of ALS with FUS pathology are associated with mutations in the corresponding gene FUS, the vast majority of FTLD-FUS cases appear to be sporadic (Mann and Snowden, 2017). This evidence concerns the gene FUS and amyotrophic lateral sclerosis.