As reverse transcriptase has both RNA-dependent DNA polymerase as well as ssDNA-dependent DNA ploymerase activity, then, why, while making RNA to cDNA, we do not see an amplification of cDNA formed?
Once the RNA-specific primers are bound, they do not melt again during cDNA synthesis, so they have no opportunity to bind to cDNA. Also, after cDNA synthesis, you have RNA/DNA hybrids in your solution. Melting them requires elevated temperatures, but cDNA synthesis is done at constant temperature.
To amplify DNA (cDNA), first you need to denature/melt the double strands at 95 degree Celsius-a temperature only genetically-engineered heat tolerant DNA polymerase can survive. Plus, as the name suggests, reverse transcriptase can only specifically convert mRNA into cDNA......
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