Is Rett syndrome caused by a triplet repeat expansion?
S Hofferbert1, N C Schanen, S S Budden
1Department of Genetics, Stanford University School of Medicine, California, USA.
Neuropediatrics
|June 1, 1997
Summary
This study investigated triplet repeat expansions (TREs) as a cause for Rett syndrome. Researchers found no evidence of large TREs, ruling out this specific genetic mechanism for the disorder.
Area of Science:
- Genetics
- Neurology
- Molecular Biology
Background:
- Rett syndrome is a rare neurodevelopmental disorder.
- While typically sporadic, rare familial cases and phenomena like anticipation suggested a potential genetic cause.
- Triplet repeat expansions (TREs) were hypothesized as a possible mechanism.
Purpose of the Study:
- To systematically screen Rett syndrome patients and controls for triplet repeat expansions (TREs).
- To investigate the potential role of TREs in the etiology of Rett syndrome.
Main Methods:
- Utilized a modified Repeat Expansion Detection (RED) assay.
- Screened 26 sporadic and six familial Rett probands and controls.
- Assay was previously validated for detecting expanded disease alleles in other genetic disorders.
Main Results:
- No significant triplet repeat expansions (TREs) were detected in the screened Rett syndrome cohort.
- The findings exclude large TREs as a causative factor for Rett syndrome.
- The possibility of small TREs, masked by normal population variations, cannot be entirely ruled out.
Conclusions:
- Large triplet repeat expansions (TREs) are not a cause of Rett syndrome.
- Further investigation into smaller, potentially masked TREs may be warranted.
- This study narrows down the potential genetic causes of Rett syndrome.
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