One approach to quantitate RNA is the use of a known number of competitive internal standard molecules that are reverse-transcribed and subsequently co-amplified under the same reaction conditions as the target sequence (3). This technique, called competitive reverse transcription polymerase chain reaction (cRT-PCR) has been applied to monitor the level of hepatitis C virus (HCV) RNA in patient...

Current quantitative PCR protocols are only indicative of the relative quantity of a target sequence to a standard since no means of estimating the amplification rate is available as yet. The variability of PCR performed on isolated cells has already been reported by several authors, but it could not be extensively studied due to lack of a system for doing kinetic data acquisition and of statis...