While premutation carriers can develop health issues such as Fragile X-associated tremor/ataxia syndrome (FXTAS), most commonly in men, and Fragile X-associated primary ovarian insufficiency (FXPOI) in women6, in general, only individuals with a full mutation have gene hypermethylation, subsequent reduction in FMRP expression and FXS. Here, FMR1 is linked to fragile X syndrome.