Cyro-electron microscopy of tau filaments from people with corticobasal degeneration reveals a previously unseen four-layered fold, distinct from the filament structures seen in Alzheimer'
s disease and chronic traumatic encephalopathy.
Corticobasal degeneration (CBD) is a neurodegenerative tauopathy-a class of disorders in which the tau protein forms insoluble inclusions in the brain-that is characterized by motor and cognitive disturbances(1-3). The H1 haplotype of MAPT (the tau gene) is present in cases of CBD at a higher frequency than in controls(4,5), and genome-wide association studies have identified additional risk factors(6). By histology, astrocytic plaques are diagnostic of CBD7,8
