ABSTRACT
Between 1991 and 1993 Roche and Perkin-Elmer reported on a new PCR assay called Taqman [3-5] (Fig. 2). Taqman is similar to traditional PCR except that the reaction contains a fluorescence resonant energy transfer probe (FRET). The probe typically contains a green fluorescence dye (6-Fam), termed the reporter, at one end and an orange fluorescence dye (Tamra), termed the quencher, at the opposite end. The close proximity of the dyes causes the quencher to suppress (or absorb) fluorescence emission by the reporter. As probe hybridizes to the amplicons during PCR, it is cleaved by the nuclease activity of the Taq DNA polymerase. The reporter is liberated from the effects of the quencher, and the resultant increase in green fluorescence emission can be monitored with an external fluorescence detector. The amount of fluorescence is proportional to the number of amplicons generated in the reaction.
