In AD, CSF markers of amyloid and tau pathology are now frequently employed in many MASS.8 Lumbar puncture (LP) is typically well tolerated in these settings.9 Additionally, the recent availability of amyloid and tau positron emission tomography (PET) in certain jurisdictions allows non-invasive assessment of AD pathology.10 11 Progress in the field of biomarker development has not been solely confined to the field of AD. The gene discussed is MAPT; the disease is Alzheimer disease.