Since the recent development of the Roche Elecsys® assay for Alzheimer's disease core CSF biomarkers, amyloid beta 1–42, phosphorylated tau at serine 181 (P-tau), as well T-tau (31, 37), T-tau has been measured in the NDDL since 2020 using the Elecsys® Tau assay. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.