In the first part of this method or protocol, the linear range of amplification is determined by carrying out 10 identical PCRs in the presence of [{alpha}-32P]dCTP and stopping one reaction after every two cycles.  Amplification products are quantified on a denaturing polyacrylamide gel and the results plotted on a graph (counts per minute vs. cycle number).  Total RNA is used as an internal control.

Protocol: Relative RT-PCR: Determining the Linear Range of Amplification and Optimizing the Primers:Competimer