The structure and biological function of circular RNAs (circRNAs) in regulating gene expression in a cell is far from known. CircRNAs are unique molecules that contain potent regulatory elements. CircRNAs actively interact with miRNAs (sponging), affecting their regulation and functions. In addition, circRNAs have roles in transcriptional regulation, splicing, and peptide synthesis. With all these properties, circRNAs could play an essential role in diseases, especially Alzheimer’s. Their role in early diagnosis, previous to present symptoms, prognosis associated with neuropathological AD of specific circRNAs, and one of their primary functions is to act as a sponge for miRNAs, which could be a starting point for future gene therapy. This review aims to summarize the current knowledge of these exciting molecules and their potential use as new markers for AD risk. This article will focus on circRNAs deregulated in Alzheimer’s.
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