Knockout of BACE1 gene (not BACE2) was found to lead to hypomyelination through interference with the processing of neuregulin-1; however, a recent report demonstrated that BACE1 inhibitors did not affect the neuregulin-1 processing significantly, ensuring the safety of BACE1 inhibition in AD therapy, to some extent [11]. This evidence concerns the gene NRG1 and Alzheimer disease.