BACE1 and Alzheimer disease: MicroRNAs (miRNAs) are involved in posttranscriptional gene regulation.324–327 The decreased expression of miRNA-107 (miR-107) in AD may accelerate disease progression by regulating the expression of BACE1.328 In SAD patients, the expression of miR-29a/b-1 is inversely correlated with BACE1 expression.329 Only one clinical trial related to miRNAs is underway.