C9orf72 and frontotemporal dementia: Considering that STING activation has been observed in human iPSC-derived neurons harboring the C9orf72 hexanucleotide expansion [107] and that cortical iron accumulation has been demonstrated in C9orf72-FTD cases [54], it is then tempting to speculate that brain iron overload associated with the C9orf72 mutation might be indirectly induced by the STING activation derived by the C9orf72 mutation itself.