Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by a CGG triplet repeat expansion within the 5′ UTR of FMR1. Normally, individuals possess between 5 and 54 CGG repeats, and full mutation CGG repeats greater than 200 lead to the neurodevelopmental disease fragile X syndrome (FXS), which results from the excessive methylation of FMR1 and loss of FMRP protein (Kremer et al., 1991; Verkerk et al., 1991; Hagerman and Hagerman, 2002; Colak et al., 2014). The gene discussed is FMR1; the disease is fragile X syndrome.