Antemortem PET studies of [18F]THK5351 SUVR and postmortem neuropathologic studies in progressive supranuclear palsy (32) and AD (29), including ex vivo autoradiography with the selective reversible MAO-B inhibitor lazabemide (32), reported that [18F]THK5351 binding originates, to a large extent (approximately 50%), in reactive astrocytes that express increased levels of MAO-B (31). This evidence concerns the gene MAOB and Alzheimer disease.