Sleep abnormalities mimicking anti-IgLON5 can be observed in the MM2-thalamic subtype of sporadic Creutzfeldt-Jakob disease with Lewy bodies, whereas patients with gaze palsy and postural instability – tending to be diagnosed with probable PSP – can also develop these symptoms as a result of anti-IgLON5 disease (18–20). Here, IGLON5 is linked to sporadic Creutzfeldt-Jakob disease.