To this aim, we used the B-4 -a commercial anti-APP specific antibody (aa 672-714 epitope)- the D54D2 -another commercial antibody selective for the Aβ1-42 peptide- and the cleavage-specific monoclonal NH2htau antibody (D25-(QGGYTMHQDQ) epitope, phosphorylation-independent state (Corsetti et al., 2020; Latina et al., 2021b) which selectively detects the neurotoxic AD-relevant 20–22 kDa fragment (NH2htau), both in brain and in eye. The gene discussed is APP; the disease is Alzheimer disease.