Immune sera, but not control sera bound various monomeric and oligomeric forms of tau in brain extracts from non-AD control (tangle stage 2), MCI (tangle stage 1), mild (tangle stage 4), moderate (tangle stage 5) and severe (tangle stage 6) AD cases detected by western blot (Fig. 3e). The gene discussed is MAPT; the disease is Alzheimer disease.