Related Experiment Videos
MECP2 is highly mutated in X-linked mental retardation
P Couvert1, T Bienvenu, C Aquaviva
1INSERM Unité 129-ICGM, CHU Cochin 24 Rue du Faubourg Saint Jacques, 75014 Paris, France.
Human Molecular Genetics
|April 20, 2001
Summary
Mutations in the MECP2 gene are linked to non-specific X-linked mental retardation (MRX). This study identified novel MECP2 mutations in MRX families and sporadic cases, suggesting MECP2 screening for mental handicap diagnosis.
Area of Science:
- Genetics
- Molecular Biology
- Neuroscience
Background:
- The methyl-CpG binding protein 2 (MECP2) gene, located on Xq28, is known to be involved in Rett syndrome (RTT).
- Genetic evidence suggests other genes on Xq28, besides RabGDI1 and FMR2, contribute to non-specific X-linked mental retardation (MRX).
Observation:
- This study investigated the MECP2 gene in families with MRX.
- Two novel MECP2 mutations (E137G and R167W), distinct from those in RTT, were identified in MRX families.
- Screening of 185 patients negative for fragile X syndrome revealed mutations in MECP2 in four sporadic cases of mental retardation (MR).
Findings:
- The study identified novel mutations P399L and R453Q, and a previously described mutation A140V in the MECP2 gene in patients with MR.
- The frequency of MECP2 mutations in the screened mentally retarded population is comparable to fragile X syndrome (FMR1) CGG repeat expansions.
- These findings demonstrate the involvement of MECP2 in non-specific X-linked mental retardation.
Implications:
- Systematic screening of the MECP2 gene in patients with mental handicap can significantly advance molecular diagnosis.
- This research offers improved genetic counseling for individuals with mental retardation.
- The findings highlight MECP2 as a crucial gene in the etiology of various forms of mental handicap.