MAPT and tauopathy: Importantly, some next-generation tau-PET tracers show a strong affinity to 4-repeat tau, which is predominantly present in mild disease.5 Thus, [18F]PI-26206 may have more potential to detect tau deposition in mild CTE cases compared to [18F]RO-948 and [18F]MK-6240, which did not indicate relevant binding in 4-repeat tauopathies in vivo or in vitro.