Several tau tracers havebeen developed for positron emission tomography(PET) imaging.13 [18F-]Flortaucipir(AV-1451 or T807),14 representing one ofthe first-generation tau PET tracer, was approved by FDA 2020 fordiscriminating AD from other non-AD dementia.15 Several second-generation tau PET tracers, including [18F-]MK6240,16,17 [18F-]RO-948,18 [18F-]PI2620,19−21 and [18F-]PM-PBB3,22 have shown high bindingaffinity in the brains of AD patients, and PI2620 and PM-PBB3 havealso been reported to bind to tau in PSP20,22 and CBD23 patients. Here, MAPT is linked to Alzheimer disease.