One of the main arguments used in favor of a putatively central role for miRNAs in AD, is that many of the molecules with central roles in disease pathogenesis, such as APP [100–112], β-secretase (BACE1) [104, 111, 113–124], APOE [125–127] and TAU [33, 61, 64, 128–130], are direct or indirect miRNA targets. The gene discussed is APP; the disease is Alzheimer disease.