Low significance of MECP2 mutations as a cause of mental retardation in Brazilian males

Brain Dev. 2007 Jun;29(5):293-7. doi: 10.1016/j.braindev.2006.09.012. Epub 2006 Nov 3.


MeCP2 is a protein that selectively binds to methylated cytosines through its methyl-CpG-binding domain (MBD) and connects DNA methylation to transcriptional repression. Mutations in MECP2 gene, located in Xq28, have been reported as being the major cause of Rett syndrome and are also associated with some cases of X-linked mental retardation in both males and females. In this study, we present the first screening in the MECP2 gene in a Brazilian cohort of 239 unrelated males with idiopathic mental retardation. Eight sequence variations were observed in 10 patients: one novel putative pathogenic variant, two never described variants of unknown pathogenic value and five non-pathogenic variations. We conclude that in mentally retarded Brazilian males, non-pathogenic variants in the MECP2 gene are more common than actual pathogenic mutations, and therefore alterations in this gene have a weak relationship with mental retardation in males.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brazil / epidemiology
  • Child
  • Child, Preschool
  • Cognition Disorders / genetics
  • Cognition Disorders / psychology
  • Cohort Studies
  • DNA / genetics
  • Genetic Variation
  • Humans
  • Infant
  • Intellectual Disability / epidemiology
  • Intellectual Disability / genetics*
  • Intellectual Disability / psychology
  • Introns / genetics
  • Male
  • Methyl-CpG-Binding Protein 2 / genetics*
  • Mutation / genetics*
  • Mutation, Missense / genetics
  • Reverse Transcriptase Polymerase Chain Reaction


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