Quantitative PCR evaluation of deletions/duplications identified by array CGH

Area of Science:

• Genetics
• Molecular Biology
• Bioinformatics

Background:

• Array comparative genomic hybridization (aCGH) is a primary tool for detecting genomic copy number variations.
• Confirmation of aCGH findings using independent methods is crucial for clinical relevance.
• Quantitative PCR (qPCR) offers a cost-effective validation approach.

Purpose of the Study:

• To evaluate the efficacy of quantitative PCR (qPCR) in confirming array comparative genomic hybridization (aCGH)-detected genomic imbalances.
• To assess the impact of aberration size and probe coverage on confirmation rates.
• To establish guidelines for validating aCGH results.

Main Methods:

• Selected samples with potentially clinically relevant imbalances (DLRS <0.2) detected by aCGH.
• Employed quantitative PCR (qPCR) as the independent validation technology.
• Analyzed confirmation rates based on the number of probes used in the aCGH assay.

Main Results:

• Overall confirmation rate of 86.5% (102/118 cases) using qPCR.
• Imbalances detected by fewer than 10 probes showed lower confirmation rates (26.8% unconfirmed).
• Imbalances detected by 20 or more probes were consistently confirmed (100%).

Conclusions:

• qPCR is a reliable method for validating aCGH-detected genomic imbalances.
• Aberration size, indicated by probe coverage, is a critical factor influencing confirmation reliability.
• Validation of aCGH results is recommended for imbalances detected by fewer than 10 probes.