The Fragile X Family of Disorders: A Model for Autism and Targeted Treatments

  title={The Fragile X Family of Disorders: A Model for Autism and Targeted Treatments},
  author={Randi J. Hagerman and Susan M. Rivera and Susan M. Rivera and Paul J. Hagerman},
  journal={Current Pediatric Reviews},
CGG-repeat expansion mutations of the fragile X mental retardation 1 (FMR1) gene are the leading known cause of autism and autism spectrum disorders (ASD). Full mutation expansions (>200 CGG repeats) of the gene are gen- erally silenced, resulting in absence of the FMR1 protein and fragile X syndrome. By contrast, smaller expansions in the premutation range (55-200 CGG repeats) result in excess gene activity and RNA toxicity, which is responsible for the neurodegenerative disorder, fragile X… 

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