Differential polymerase chain reaction with serial dilutions for quantification of MYCN gene amplification in neuroblastoma

Background: MYCN amplification is a powerful prognostic marker in neuroblastoma. Since MYCN status guides therapy results should be available promptly after diagnosis. Material and Methods: We used a differential PCR assay to analyze neuroblastoma samples obtained from 25 patients diagnosed and treated at our Institution. Serial dilutions of test DNA in control DNA were performed prior to differential PCR in order to quantitate the MYCN copy number. Results: MYCN amplification was identified by differential PCR in five samples out of twenty five. The serial dilutions of amplified DNAs performed before the PCR reaction allowed a precise estimation of the copy number in the 5 samples with amplification. Conclusions: The present results confirm differential PCR assay as an easy, sensitive and rapid technique to evaluate the MYCN gene amplification in neuroblastoma. Serial dilutions accurately estimate the gene copy number allowing the early onset of the appropriate treatment.