FMR1 and fragile X syndrome: By examining methylation within the FMR1 ‘minimal’ promoter [20] and the adjacent regions in transformed lymphoblast cell lines from FXS individuals, ‘high-functioning’ individuals with UFM alleles, and controls, we identified new regions differentially methylated in individuals with FMR1-related disorders [3,16], with Fragile X-Related Element 2 (FREE2) located largely within FMR1 intron 1 and Fragile X-Related Element 3 (FREE3) located within FMR1 intron 2.