Given the fact that neuroinflammation (e.g., glial activation) has been indicated in the pathophysiology of a variety of neurodegenerative diseases [121], and even though there is still debate whether it is a cause or a consequence of these diseases, the above findings have raised an important question: does immune system dysregulation, and in particular glial cells dysfunction, contribute to the C9orf72 ALS/FTD pathogenesis? Here, C9orf72 is linked to frontotemporal dementia.