Deleterious mutations in exon 1 of MECP2 in Rett syndrome

Eur J Med Genet. 2006 Jul-Aug;49(4):313-22. doi: 10.1016/j.ejmg.2005.11.002. Epub 2005 Dec 20.


The MECP2 gene is responsible for 80-85% of typical cases of Rett syndrome with deleterious mutations affecting exons 3 and 4. Recently, an alternate transcript including exon 1 was discovered with a new protein isoform (MeCP2_e1) much more abundant in brain. We screened exon 1 of MECP2 for mutations and for large rearrangements in a panel of 212 typical cases of Rett syndrome and one family case with atypical Rett syndrome. We identified two deleterious mutations (c.48_55dup and c.62+2_62+3del) and four large rearrangements encompassing exon 1 of MECP2. We also identified the c.16_21dup alteration formerly reported as c.3_4insGCCGCC and give additional support to classify this sequence variation as polymorphic. In our large panel of typical Rett, mutations affecting exon 1 of MECP2 represent 1% of the deleterious alleles. This study confirms that mutations in exon 1 of MECP2 are a rare cause of Rett syndrome.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child, Preschool
  • Exons / genetics
  • Female
  • Humans
  • Methyl-CpG-Binding Protein 2 / genetics*
  • Mutation
  • Rett Syndrome / genetics*


  • MECP2 protein, human
  • Methyl-CpG-Binding Protein 2