Reverse transcription

Reverse transcription involves the synthesis of a DNA strand complimentary to mRNA. Synthesis is catalyzed by the reverse transcriptase enzyme. The complimentary DNA is commonly referred to as cDNA. cDNA can then be used for both qualitative and quantitative analyses. Qualitative analyses involve standard PCR for which a simple yes or no question is asked ....... is a particular mRNA expressed? Qualitative analyses are commonly referred to as reverse transcription PCR (RT-PCR). Quantitative analyses involve assessing the relative mRNA expression levels at the time the RNA was harvested. Quantitative analyses are commonly referred to as qPCR or real time PCR.

Reverse transcriptase kits can be purchased from Thermo Fisher Scientific. A primer such as oligo(dT) also available from Thermo Fisher Scientific, is required for the reverse transcription reaction. The oligo(dT) primer binds with the polyA tail of the mRNA. Following reverse transcription, 10% of the reaction volume is usually enough for use as a template for standard PCR.