Still, it has only been in the recent past that the quantification of Aβ42 and 40 and their ratio, total-tau (t-tau) and phosphorylated-tau (p-tau) protein levels in CSF using enzyme-linked immunosorbent assay (ELISA) have become a cornerstone of the routine diagnostics of patients with cognitive complaints as they allow for an early and reliable diagnosis of AD pathology2,4,5,10,11. Here, MAPT is linked to Alzheimer disease.