The cerebrospinal fluid (CSF) is in direct contact with brain tissue and provides insight into changes experienced by the brain.6 A well‐validated finding for the prediction of AD that displays sensitivity and specificity is that the CSF of affected patients sees a reduction in the levels of Aβ42, but increased total and phosphorylated Tau levels.7 A lumbar puncture, required to extract CSF, is an invasive procedure and thus is far from ideal. Here, MAPT is linked to Alzheimer disease.