BACE1 and Alzheimer disease: AD research using Drosophila frequently implies one of two approaches; either the Aβ peptides are fused to a secretion sequence and directly produced from transgenes (the Aβ fly model) or the Aβ peptides are produced by the processing of human AβPP (the AβPP‐BACE1 fly model) 10, 14, 35, 36, 37, 38.