Evaluation of the reliability of chromosomal imbalances detected by combined use of universal DNA amplification and comparative genomic hybridization

Comparative genomic hybridization (CGH) analysis of microscopic tumor sampl es is allowed by universal DNA amplification using degenerate oligonucleoti de primed-PCR (DOP-PCR). To evaluate the reliablity of DOP-PCR CGH, we perf ormed DOP-PCR CGH and standard CGH in parallel using DNAs extracted from 10 malignant tumors of the hepatobiliary tract and pancreas. Similar results were obtained by both methods with a few exceptions, indicating that DOP-PC R CGH provides cytogenetic information equivalent to that obtained from sta ndard CGH. We also investigated the sensitivity of DOP-PCR CGH using sequen tial dilutions of DNA from microdissected tumor cells. DOP-PCR using 100 to 800 pg of template DNA yielded successful CGH results. However, less than 50 pg of template DNA was not suitable because of the small amount of gener ated DNA. These findings suggest that DOP-PCR CGH is applicable for CGH ana lysis of tiny specimens which are too small for standard CGH. Accordingly, DOP-PCR CGH analysis may become a useful method in clinical laboratory exam ination.