A very recent study of the GENFI including presymptomatic and symptomatic GRN mutation carriers investigating the temporal cascade of multimodal biomarkers by means of discriminative event-based modeling (DEBM) demonstrated that, both in bvFTD and in nfvPPA, serum NFL is—together with language—the first biomarker to become abnormal in this genetic form of FTD (Panman et al., 2021). The gene discussed is GRN; the disease is frontotemporal dementia.