FMR1 and fragile X-associated tremor/ataxia syndrome: C9orf72 mRNA with an enlarged 5’-UTR that includes the G4C2 repeats, is similar to FMR1 transcripts associated with fragile X-associated tremor ataxia syndrome (FXTAS), caused by moderate (<200) CGG repeat expansions in the 5’-UTR of the FMR1 gene [44].