Premutation carriers do not show early-childhood-onset intellectual disability syndrome, and paradoxically, they have abnormally high levels of FMR1 mRNA, which predisposes them to a late-onset neurodegenerative disorder called fragile X-associated tremor/ataxia syndrome (FXTAS) [13]. The gene discussed is FMR1; the disease is fragile X-associated tremor/ataxia syndrome.