Comparison of PCR and ested PCR for amplification of DNA from paraffin embedded tissues

Paraffin embedded tissues are stored in hospital archives for years to decades. These FFPE archived samples are an extremely valuable source for genetic studies. Unfortunately, DNA from FFPE are weaker even than formalin embedded tissue and PCR amplification from these samples may leads to negative results. Hence, efficient methods are of critical importance for amplification of DNA extracted from FFPE samples. In this study we compared conventional PCR and Nested PCR for amplification of k-ras gene on DNA recovered from FFPE samples. Method: DNA was extracted from 70 FFPE samples by modified phenol-chloroform proteinase K method. PCR and Nested PCR were used for amplification of K-ras gene followed by RFLP analysis. Results: Among 70 samples were analysed, 35 samples were positive in conventional PCR, whereas, 65 samples were positive in Nested-PCR amplification. The strength of amplicon was higher in Nested-PCR than conventional PCR. Conclusion: The results obtained in this study indicated the efficiency of Nested-PCR for amplification from FFPE samples.

Keywords:

ested PCR , FFPE , amplification , conventional PCR