In the present study we investigated the ability of plasma Aβ42/40, p‐tau181, p‐tau181/Aβ42, GFAP, and NfL to discriminate groups along the continuum of three neurological diseases: AD, FTD, and DLB, in a large international multi‐center cohort. The gene discussed is NEFL; the disease is Lewy body dementia.