RNA-mediated pathogenesis in fragile X-associated disorders

Noncoding RNAs play important and diverse regulatory roles throughout the genome and make major contributions to disease pathogenesis. The FMR1 gene is involved in three different syndromes: fragile X syndrome (FXS), primary ovarian insufficiency (POI), and fragile X-associated tremor/ataxia syndrome (FXTAS) in older patients. Noncoding RNAs have been implicated in the molecular pathogenesis of both FXS and FXTAS. Here we will review our current knowledge on the role(s) of noncoding RNAs in FXS and FXTAS, particularly the role of the microRNA pathway in FXS and the role of noncoding riboCGG (rCGG) repeat in FXTAS.