Recently, plasma NT1, targeting shorter, N-terminal-bearing fragments of tau (BT2/Tau12), was able to differentiate Alzheimer’s disease from control subjects and predict future cognitive decline, suggesting that N-t-tau fragments could be more suitable blood biomarkers.18,31,39 In this study, we identified a novel plasma N-terminal biomarker (NTA) that also showed higher concentrations in Alzheimer’s disease compared with controls both in the pilot and clinical cohorts. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.