C9orf72 and frontotemporal dementia: We found higher CSF NfL values in the genetic cohort than in the sporadic group (p = 0.013) and, within genetic FTD, a higher increase in plasma GFAP levels in GRN mutation carriers than in individuals with C9orf72 or other mutations (p = 0.029 and p = 0.036, respectively) (Additional file 1: Table S5).