FMR1 and fragile X-associated tremor/ataxia syndrome: Recently, it was shown that the expansion of CGG repeats in the 5′-UTR of the Fmr1 gene, which is closely associated with fragile X-associated tremor/ataxia syndrome (FXTAS), leads to the production of polyglycine or polyalanine by RAN translation (Todd et al., 2013), whose spontaneous aggregation may contribute to the FXTAS pathologies.