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Updated: May 18, 2026
09:16
Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
High-resolution SNP array analysis of patients with developmental disorder and normal array CGH results
Linda Siggberg1, Sirpa Ala-Mello, Ala-Mello Sirpa
1Department of Pathology, Haartman Institute, University of Helsinki, Finland. linda.siggberg@helsinki.fi
BMC Medical Genetics
|September 19, 2012
Summary
Ultra high-resolution SNP arrays did not improve diagnoses for developmental disorders in this study. Further research is needed to identify the causes of these complex genetic conditions.
Area of Science:
- Genomics
- Medical Genetics
Background:
- Microarray technology has improved diagnosing developmental disorders.
- Copy number analysis aids diagnosis in up to 20% of patients with normal karyotyping.
- Many developmental disorder cases remain undiagnosed.
Purpose of the Study:
- To investigate ultra high-resolution SNP arrays for diagnosing developmental disorders.
- To characterize genomic aberrations in patients with normal array CGH results.
Main Methods:
- Analyzed 35 patients with unexplained developmental disorders using Genome-Wide Human SNP array 6.0.
- Filtered data based on copy number variant frequencies and phenotypically relevant genes.
- Identified regions of allelic homozygosity potentially correlating with patient phenotypes.
Main Results:
- No pathogenic copy number aberrations were detected.
- Identified candidate genes in four patients, but results were unconfirmed.
- Vast amounts of polymorphic and non-informative data were generated.
Conclusions:
- Ultra high-resolution SNP arrays did not enhance diagnoses in this cohort.
- Study findings are limited by the small patient sample size.
- Recurrence of clustered allelic homozygosity was detected.
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