Identification of microRNAs Associated With Human Fragile X Syndrome Using Next Generation Sequencing

Abstract

Fragile X syndrome (FXS) is caused by a mutation in the FMR1 gene which can lead to a loss or shortage of the FMR1 protein. This protein interacts with specific miRNAs, and a change can cause a range of neurological disorders. Therefore, miRNAs could act as a novel class of potential biomarkers for common CNS diseases. The aim of this study was to test this theory by exploring the expression profiles of various miRNAs in Iranian FXS patients using deep sequencing-based technologies, and validate the miRNAs affecting expression of the FMR1 gene. Blood samples were taken from 15 patients with FXS (9 males, 6 females) and 12 controls. 25 miRNAs were differentially expressed in individuals with FXS compared to controls. Levels of 9 miRNAs were found to be significantly changed (3 upregulated and 6 downregulated). In FXS patients, the levels of hsa-miR-532-5p, hsa-miR-652-3p and hsa-miR-4797-3p were significantly upregulated while levels of hsa-miR-191-5p, hsa-miR-181-5p, hsa-miR-26a-5p, hsa-miR-30e-5p, hsa-miR-186-5p, and hsa-miR-4797-5p exhibited significant downregulation; and these dysregulations were confirmed by RT‐qPCR. This study present altered miRNA expression in blood samples from FXS patients, which could be used for diagnostic, prognostic, and treatment purposes. Larger studies are required to confirm these preliminary results.