APP and Alzheimer disease: According to the results of the study by Faghihi MA, the expression of BACE1-AS and BACE1 mRNA is upregulated and the Aβ1-42 content is markedly increased in the brains of patients with AD and APP-tg19959 APP transgenic mice, suggesting that the abnormal activation of BACE1-AS is involved in the pathogenesis of AD [12].