High expression of miR‐510 was associated with CGG expansion located at upstream of FMR1 into full mutation

MicroRNAs (miRNAs) have been found to play an important role in the regulation of gene expression in eukaryotic organisms at the posttranscriptional level. More than half of miRNA genes have been recognized to be located in different fragile sites. Among them, miR‐510 was located on chromosome X in the 27.3Xq region, flanking to a fragile X site. The CGG expansion and its methylation at the promoter of FMR1 located in this fragile site were associated with clinical symptoms of fragile X syndrome (FXS). The aim of the current study was to investigate whether the miR‐510 expression was correlated with the CGG expansion of FMR1 in female carriers of full mutation. For this purpose, mesenchymal stem cells were isolated from peripheral blood of FMR1 full mutation female carriers. After differentiation of these cells into neuronal cells, the expression of miR‐510 was analyzed by quantitative polymerase chain reaction. Furthermore, the target genes of miR‐510 in the nervous system were also predicted by in silico method. The obtained results indicated that the CGG expansion of FMR1 was associated with the enhanced expression of miR‐510. Furthermore, the bioinformatics analysis suggested that VHL and PPP2R5E genes could be considered as the most important target genes of miR‐510 in the nervous system. This study showed that miR‐510 and its target genes, specifically VHL and PPP2R5E, may represent the new targets for future therapy options of FXS. The aim of the current study was to investigate whether the expression of miR‐510 was correlated with the CGG expansion of FMR1 in female carriers of full mutation. The obtained results could provide more understanding of pathogenesis of fragile X syndrome (FXS) and represent the new targets for FXS treatment in future.