Synthesis of extensive, possibly complete, DNA copies of poliovirus RNA in high yields and at high specific activities.

The synthesis of large, possibly complete, complementary DNA (cDNA) copies of poliovirus RNA by avian myeloblastosis virus DNA polymerase is described. The cDNA consists of two size classes, the larger of which is approximately 7500 nucleotides. In the presence of excess deoxynucleoside triphosphates, ribonucleoside triphosphates, or sodium pyrophosphate, only the larger material is obtained. Yields of the large cDNA are 50-75% of the input RNA.