Application of array-based comparative genomic hybridization to pediatric neurologic diseases

Area of Science:

• Genetics
• Genomics
• Clinical Diagnostics

Background:

• Array comparative genomic hybridization (array-CGH) analyzes chromosomal copy number variations.
• Conventional karyotyping is a standard genetic diagnostic tool.
• Pediatric neurology patients often present with complex genetic conditions.

Purpose of the Study:

• To evaluate the clinical utility and diagnostic yield of array-CGH.
• To compare array-CGH with conventional karyotyping in pediatric neurology.
• To assess array-CGH for diagnosing genome abnormalities in children.

Main Methods:

• Study included 87 pediatric neurology patients with developmental delay, mental retardation, dysmorphic features, or epilepsy.
• DNA samples underwent array-CGH using Roche NimbleGen 135K arrays.
• Results were compared with G-band karyotyping and literature data.

Main Results:

• Chromosome imbalances were detected in 32.2% of patients (28/87).
• Array-CGH identified 9 cases also detected by karyotyping, plus additional abnormalities.
• Abnormal array results were linked to phenotypes in at least 19 patients, with varying rates across clinical symptoms.

Conclusions:

• Array-CGH is a valuable tool for diagnosing unknown genome abnormalities in pediatric neurology.
• The technique demonstrates high diagnostic yield for complex genetic disorders in children.
• Array-CGH complements or surpasses conventional karyotyping in this patient population.