To evaluate whether the observed in vitro binding properties of [18F]AV1451 are shared with other first-generation tau-PET tracers also showing consistently elevated binding in SV PPA cases in vivo [13], we performed a similar autoradiography binding experiment with [18F]THK5351 in a subset of cases (case 4, 6, 8, and 11) (Table 1). This evidence concerns the gene MAPT and primary progressive aphasia.