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Updated: Jun 6, 2026

Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
De novo unbalanced translocation 2;4 characterized by metaphase CGH and array CGH in a child with mental retardation
A Debost-Legrand1, Y Capri, L Gouas
1Service de Cytogénétique Médicale, Faculté de Médecine, CHU Clermont-Ferrand, Université Clermont 1, BP 38, 1 place Lucie-Aubrac, 63003 Clermont-Ferrand cedex 1, France.
Background:
It is known from postnatal diagnosis that imbalances of the subtelomeric regions contribute significantly to idiopathic mental retardation.
Patient And Methods:
We report a case of a 4-year-old child with growth retardation, minor physical abnormalities, hypotonia and developmental delay associated with a derivative chromosome 4. Molecular cytogenetic investigations were performed to characterize the chromosomal rearrangement.
Results:
Multi fluorescence in situ hybridization revealed the presence of chromosome 2 material on the derivative chromosome 4. Metaphase comparative genomic hybridization detected a terminal 4q34 deletion. Array CGH analysis could precise breakpoints with duplication 2q36 → qter. The clinical phenotype was similar to those described in cases with a trisomy 2qter.
Conclusion:
This study emphasizes the value of array CGH to detect or characterize chromosome rearrangements in mentally retarded patients. Unlike metaphase CGH, the high resolution of array CGH in subtelomeric regions allows an accurate description of chromosomal aberrations.
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