In addition to the production of sAβPPβ, Aβ1-42 and CTFs in the AβPP-BACE1 flies, other Aβ isoforms with different lengths and post-translationally modified N-terminal truncated variants of the Aβ peptide are most likely also produced when AβPP is processed in the flies, as has been found in studies in AβPP-overexpressed cell lines and in brain tissue from AD patients (Portelius et al., 2010, 2013). Here, BACE1 is linked to Alzheimer disease.