GRN and frontotemporal dementia: Attempts to describe the earliest phases have recently been made in monogenic FTD, where the study of at-risk subjects carrying pathogenetic mutations in chromosome 9 open reading frame 72 (C9orf72), progranulin (GRN) and microtubule-associated protein tau (MAPT) has allowed to depict the stages in proximity of dementia conversion [5, 6].