Plasma amyloid-beta (Αβ)42, Aβ40 and total tau (in CU controls and Alzheimer’s disease patients) and phosphorylated tau at threonine-181 (P-tau181), neurofilament light (NfL) and glial fibrillar acidic protein (GFAP) levels (in all participants) were measured using the single-molecule array platform. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.