I n the last few years, molecular hybridization methods have been used extensively in basic and applied virology because of their technical flexibility and high specificity. Using these techniques, the detection of DNA and RNA viruses directly from clinical specimens, the analysis of the specific transcriptional activity of viral genes in vitro and in vivo, and the study of virus-host relations...

Those who have worked in the field of quantitative polymerase chain reaction (PCR) since the early 1990s have accepted many of the tedious aspects of the early assays as routine. Difficulties associated with early quantitative PCR techniques included: (i) ensuring that the PCR was within the linear range of amplification (that portion where the PCR signal is directly proportional to the input c...

Unlike classical end-point analysis PCR, real-time PCR provides the data required for quantification of the target nucleic acid. The results can be expressed in absolute terms by reference to external quantified standards or in relative terms compared to another target sequence present within the sample. Absolute quantification requires that the efficiency of the amplification reaction is the s...

We have developed a novel "real time" quantitative PCR method. The method measures PCR product accumulation through a dual-labeled fluorogenic probe (i.e., TaqMan Probe). This method provides very accurate and reproducible quantitation of gene copies. Unlike other quantitative PCR methods, real-time PCR does not require post-PCR sample handling, preventing potential PCR product carry-over conta...