MAPT and Alzheimer disease: Using the tau-PET tracer [18F] THK5317, [(S)-[18F] THK5117] and [18F] FDG in a human cerebrospinal fluid (CSF) sample of AD patients was investigated by Leuzy et al. [5] and their study found that a subtype of tau may better capture tau pathology and synaptic impairment.