PET imaging with 2-(2-([18F]fluoro)pyridin-4-yl)-9H-pyrrolo[2,3-b:4,5-c′]dipyridine ([18F]PI-2620) has demonstrated the ability to detect tau pathology in patients diagnosed with progressive supranuclear palsy (PSP) (1) and corticobasal syndrome (2,3). This evidence concerns the gene MAPT and Classical progressive supranuclear palsy.