Hi Bhargavi,

Reverse transcription-polymerase chain reaction (RT-PCR) is a sensitive in vitro method and has a crucial role in medical science and biomaterial fields.

RT-PCR uses RNA as starting material for in vitro nucleic acid amplification. The discovery of retroviral reverse transcriptase in the early 1970s ultimately made RT-PCR possible. Reverse transcriptase is an RNA-dependent DNA polymerase, catalyzing DNA synthesis using RNA as the template. The end product is known as complementary DNA (cDNA). cDNA is not subject to RNase degradation, making it more stable than RNA. In RT-PCR, the starting RNA is subsequently degraded, dsDNA is produced, and PCR amplification proceeds in the usual manner. RNA extraction kits for both manual and automated RNA purification exist and, when combined with RT-PCR, make RNA analysis in the clinical laboratory virtually as rapid and equally sensitive as PCR-based DNA amplification.

RT-PCR is commonly used in the diagnosis and quantification of RNA virus infections (e.g., human immunodeficiency virus and hepatitis C virus) and the analysis of mRNA transcripts such as those produced by translocations commonly associated with non-Hodgkin's lymphomas, leukemias, and sarcomas. Gene expression profiling is likely to have a major impact on molecular diagnostics in the coming years and will depend on RNA analysis using RT-PCR and possibly high-density arrays.

Best regards

This site is for answering research questions. Questions that can be answered by a quick Google search are against the community guidelines.

If you really want to know, then start by reading an introductory molecular biology textbook chapter, read some qPCR kit product information, and talk with colleagues who use this technique.

https://nordicbiosite.com/blog/gene-expression-analysis-rna-seq-or-real-time-pcr?fbclid=IwAR2ySPkc6_QEMyVdAqZtf-ys2D7HuMihoX1JUmA8s0-TWw8SdP1EIeG3loQ

Real-time PCR, is a more targeted approach to gene expression analysis. Total RNA is subjected to reverse transcription, and the resulting cDNA is amplified using target-specific primers in a quantitative PCR reaction. Fluorescent DNA-binding probes (target-specific) or fluorescent dsDNA-binding dyes (non-specific) are incorporated into the PCR reaction and the level of fluorescence emitted during amplification is relative to the amount of target present in the sample. Because of the requirement for target-specific primers and/or probes for each gene of interest, real-time PCR is not a catch-all technique. However, with a good set of target-specific DNA-binding probes, it is possible to multiplex i.e. analyze several targets in the same sample simultaneously.