MAPT and Alzheimer disease: Tau pathology, as assessed by AT8 immunostaining, was present throughout the occipital lobe in AD cases as neurofibrillary tangles and neuropil threads  and was significantly higher in the primary visual cortex but was minimal or absent from control and DLB cases (P < 0.05 vs control; P < 0.05 vs DLB, see Additional file 6: Figure S1).