CAPN1 and early-onset autosomal dominant Alzheimer disease: The continuous increase in calpain 1 expression will inevitably lead to excessive calcium influx into cells, resulting in a significant decline of cell survival rate; whereas selective calpain inhibitors have been proved the potency, efficacy and safety as possible therapeutics against abnormal synaptic plasticity and memory produced by the excess of amyloid-β, a distinctive marker of Alzheimer’s disease (Fà et al., 2015).