[Subtelomeric rearrangements in cryptogenic mental retardation]
A Verdú Pérez1, P L García Murillo, O García Campos
1Unidad de Neurología Pediátrica, Hospital Virgen de la Salud, Toledo, España. averdu@sescam.jccm.es
Anales De Pediatria (Barcelona, Spain : 2003)
|July 30, 2011
Summary
Subtelomeric rearrangements, chromosomal abnormalities missed by standard tests, explain 4.5% of unexplained mental retardation cases. Their presence is linked to multiple dysmorphic features or intrauterine growth retardation.
Area of Science:
- Genetics
- Cytogenetics
- Developmental Biology
Context:
- Mental retardation affects 3% of the population, with unknown origins in 50% of cases.
- Routine cytogenetic studies often fail to detect subtelomeric rearrangements.
- These rearrangements are potential causes of idiopathic intellectual disability.
Purpose:
- To investigate the frequency and clinical significance of subtelomeric rearrangements in individuals with unexplained mental retardation.
- To determine if subtelomeric aberrations are associated with specific clinical features.
Summary:
- A study utilized multiplex ligation dependent probe amplification (MLPA) on 200 subjects with unexplained mental retardation.
- Subtelomeric aberrations were detected in 9 patients (4.5%), with 8 being de novo.
- Abnormalities were significantly associated with multiple dysmorphic features and intrauterine growth retardation.
Impact:
- Subtelomeric rearrangements are a significant, though often undetected, cause of mental retardation.
- Identifying these aberrations can improve diagnostic yield in unexplained cases.
- Clinical features like dysmorphism and growth retardation can indicate the likelihood of subtelomeric aberrations.
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