FMR1 and fragile X-associated tremor/ataxia syndrome: The expansion of the CGG trinucleotide repeat within the 5’ untranslated region (UTR) of the Fragile X Mental Retardation 1 (FMR1) gene is the predominant cause of Fragile X syndrome (FXS), and the only known cause of Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI) [1].