Fragile-X syndrome and fragile X-associated tremor/ataxia syndrome: two faces of FMR1

Lancet Neurol. 2007 Jan;6(1):45-55. doi: 10.1016/S1474-4422(06)70676-7.


Recent advances in our understanding of the clinical and molecular features of the fragile-X mental-retardation 1 gene, FMR1, highlight the importance of single-gene disorders. 15 years after its discovery, FMR1 continues to reveal new and unexpected clinical presentations and molecular mechanisms. Loss of function of FMR1 is a model for neurodevelopmental and behavioural disorders, including mental retardation, autism, anxiety, and mood instability. In addition, overexpression and CNS toxicity of FMR1 mRNA causes a late-onset neurodegenerative disorder, the fragile-X-associated tremor/ataxia syndrome (FXTAS). A similar mechanism is probably involved in premature ovarian failure, which affects up to 20% of female carriers of an altered FMR1 gene.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Ataxia / drug therapy
  • Ataxia / etiology*
  • Female
  • Fragile X Mental Retardation Protein / biosynthesis
  • Fragile X Mental Retardation Protein / genetics*
  • Fragile X Syndrome / complications*
  • Fragile X Syndrome / drug therapy
  • Fragile X Syndrome / genetics*
  • Gene Expression / physiology
  • Humans
  • Male
  • Menopause / genetics
  • Menopause / physiology
  • Middle Aged
  • Pedigree
  • RNA, Messenger
  • Seizures / drug therapy
  • Seizures / etiology
  • Tremor / drug therapy
  • Tremor / etiology*


  • FMR1 protein, human
  • RNA, Messenger
  • Fragile X Mental Retardation Protein