Somatic mosaicism for a MECP2 mutation associated with classic Rett syndrome in a boy

Eur J Hum Genet. 2002 Jan;10(1):77-81. doi: 10.1038/sj.ejhg.5200745.


Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child
  • Child, Preschool
  • Chromosomal Proteins, Non-Histone*
  • Codon, Nonsense
  • DNA-Binding Proteins / genetics*
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Methyl-CpG-Binding Protein 2
  • Mosaicism / genetics*
  • Repressor Proteins*
  • Rett Syndrome / genetics*


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