Tau and 43-kDa Tar DNA-binding protein (TDP-43) are present in neurofibrillary tangles characteristic of frontotemporal lobar degeneration and AD; Aβ plaques are the hallmark of AD; and α-synuclein has been identified in the pathognomonic bodies of diffuse Lewy body disease and PD. This evidence concerns the gene MAPT and frontotemporal dementia.