The amyloid hypothesis, in turn, relates AD to theformation ofextracellular deposits of the β-amyloid peptide (βA),produced by the action of proteolytic enzymes (alpha, beta, and gammasecretase) from the amyloid precursor protein (APP), with beta-secretase1 (BACE-1, E.C. 3.4.23.46) being the most involved in the productionof those deposits., BACE-1 is responsible for hydrolyzingAPP into peptide fragments, which undergo further action by gammasecretase and then form the βA peptide. This evidence concerns the gene APP and Alzheimer disease.