Representative tau-PET ligands, including the first-generation tracers—THK tracers, T807/T808, and [11C]-PBB3—and the second-generation tracers—[18F]-MK-6240, [18F]APN-1607, and [18F]PI-2620—can reflect the timing and distribution of tau in the early phases of neurodegenerative diseases (Fodero-Tavoletti et al., 2011; Chien et al., 2014; Marquié et al., 2015; Walji et al., 2016; Marquié et al., 2017). Here, MAPT is linked to neurodegenerative disease.