FMR1 and fragile X-associated tremor/ataxia syndrome: Third, FMR1 RNA is present in the intranuclear inclusions of postmortem FXTAS brain tissue (Tassone et al., 2004), and animal and cell models expressing rCGG repeats develop similar inclusions (Jin et al., 2003; Willemsen et al., 2003; Arocena et al., 2005).