Increased activation of calpain-1 has been reported in brain samples of AD patients [26, 27] and several neuronal proteins are known substrates for calpain, e.g. αII and βII spectrin, PSD95, MAP-2, GAP-43, calcineurin, PKC, CaMKII, and NMDA receptors. The gene discussed is DLG4; the disease is Alzheimer disease.