Nowadays, the earliest pathological hallmarks such as amyloid-β and tau accumulation can be accurately measured by means of protein quantification in cerebrospinal fluid (CSF) and with positron emission tomography (PET) imaging and are as such key in the biological diagnosis of Alzheimer’s disease.2 However, measurement of these biomarkers is expensive or invasive and not suitable for broad implementation in the elderly population. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.