MAPT and Alzheimer disease: Amyloid beta 1–42 (Aβ1–42, molecular mass 4514 Da), Amyloid beta 1–40 (Aβ1–40, molecular mass 4330 Da), Tau protein (Tau) and Tau protein phosphorylated at position 181 (pTau) (molecular mass 36800–45900 Da) are proteins originating from the brain and the myelon which help to discriminate AD from other types of dementia [4].