Rett syndrome: model of neurodevelopmental disorders

J Child Neurol. 2005 Sep;20(9):718-21. doi: 10.1177/08830738050200090301.


Rett syndrome is a neurodevelopmental disorder that primarily affects girls, most of whom have mutations in the transcription regulatory gene MECP2. However, mutations in MECP2 also have been identified in normal carrier female individuals, female individuals with mild learning disabilities and features of Angelman syndrome, and male individuals with Klinefelter syndrome or Rett syndrome-like features, fatal neonatal encephalopathy, and familial X-linked mental retardation with or without motor abnormalities. Therefore, molecular testing should be considered for a wide spectrum of individuals. As such, Rett syndrome remains a clinical diagnosis. In this article, we also discuss three recent developments: (1) the recognition of significant gallbladder dysfunction, especially in those 20 years of age or younger; (2) a clinical trial of folate and betaine, which produced no objective improvement but did yield a subjective increase in attention and interaction; and (3) measurement of cerebrospinal fluid folate levels in a large cohort, which yielded normal values, indicating no need for supplementation.

Publication types

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

MeSH terms

  • Betaine / therapeutic use
  • Female
  • Folic Acid / therapeutic use
  • Gallbladder Diseases / etiology
  • Gastrointestinal Agents / therapeutic use
  • Hematinics / therapeutic use
  • Humans
  • Infant
  • Methyl-CpG-Binding Protein 2 / genetics
  • Rett Syndrome / diagnosis*
  • Rett Syndrome / drug therapy
  • Rett Syndrome / genetics


  • Gastrointestinal Agents
  • Hematinics
  • MECP2 protein, human
  • Methyl-CpG-Binding Protein 2
  • Betaine
  • Folic Acid