MAPT and early-onset autosomal dominant Alzheimer disease: The experience from the most abundant and extensively studied neurodegenerative disease, Alzheimer’s disease (AD), with specific protein-based neuroimaging positron emission tomography (PET) radiotracers and the successful measurement of amyloid beta species (Aβ42, Aβ40), tau and phosphorylated tau 181 (p-tau181) in cerebrospinal fluid (CSF), has paved the way to the development of anti-amyloid therapies and other disease-modifying therapies [6].