SORL1 and Alzheimer disease: Dickson et al (2013) showed that miR-34a represses the expression of endogenous τ protein by binding 3′ UTR of human τ mRNA in a neuroblastoma cell line M17D. Similarly, miRNAs -125b, -342, and -34a targeted BCL2, an anti-apoptotic gene. Thus, they may involve in cellular and tissue level senescence and exhibit brain ageing and ageing phenotypes (Chen et al, 2021; Chua and Tang, 2019). However, other potential mRNA targets of these miRNAs such as SORL1 and MAPT may play a crucial role in Tg mice leading to severe AD pathologies.