Mutation analysis of the methyl-CpG-binding protein 2 gene (MECP2) in Rett patients with preserved speech

Brain Dev. 2001 Dec;23 Suppl 1:S157-60. doi: 10.1016/s0387-7604(01)00378-3.


Genomic DNAs from 35 Japanese sporadic patients with Rett syndrome (RTT) were screened for DNA mutations in the entire coding region and exon-intron boundaries of methyl-CpG-binding protein 2 (MECP2). We detected mutations in 30 (85.7%) of 35 patients. Among these 35 RTT patients, five patients (14%) had the preserved speech variant of this disease. Four respective mutations (R133C, R306C, R294X, 2 base pair (bp) deletion) were found in these five patients. Two patients had the same missense mutation, R133C. The patients with the R133C mutation and one with frameshift mutation presented the relatively mild clinical presentation, and the R133C mutation was not found in any other patient without preserved speech. We confirmed that the preserved speech variant is one of the clinical phenotypes of RTT and is also caused by MECP2 mutation. We speculated that the clinical phenotype of patients with the R133C missense mutation might be mild.

MeSH terms

  • Adult
  • Central Nervous System / growth & development
  • Central Nervous System / pathology
  • Central Nervous System / physiopathology
  • Child
  • Chromosomal Proteins, Non-Histone*
  • DNA Mutational Analysis*
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Female
  • Frameshift Mutation / genetics
  • Genetic Testing
  • Genotype
  • Humans
  • Methyl-CpG-Binding Protein 2
  • Mutation / genetics*
  • Mutation, Missense / genetics
  • Phenotype
  • Repressor Proteins*
  • Rett Syndrome / genetics*
  • Rett Syndrome / physiopathology*
  • Speech / physiology*
  • Speech Disorders / genetics*


  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • MECP2 protein, human
  • Methyl-CpG-Binding Protein 2
  • Repressor Proteins