On the other hand, 5hmC was significantly decreased throughout the FMR1 locus with broader changes taking place at the promoter region and through the entire FMR1 first intron, validating in a semi-quantitative, independent manner the array-based identification of novel regions of FMR1 5mC and 5hmC changes in FXS PBMCs. Here, FMR1 is linked to fragile X syndrome.