Real-Time PCR and Real-Time RT-PCR applications in food labelling and gene expression studies

摘要

Polymerase chain reaction (PCR) as a scientific invention, has revolutionized molecular biology and led to real-time PCR and later, real-time reverse transcription PCR (Real-Time RT-PCR). These two techniques enable scientists to conduct PCR detection of amplified gene products and expression analysis of targeted genes. Quantitative polymerase chain reaction (qPCR), also called real-time polymerase chain reaction, is a recent modification to PCR that utilizes fluorescent reporter molecular techniques to monitor the production of amplified products during each cycle of the PCR reaction, and enables both detection and quantification of specific sequences in complex mixtures. Over the past decade, real-time PCR applications have rapidly changed the nature of molecular science and become widely used tools in molecular genetics research. Real-time PCR permits specific, sensitive and reproducible manipulation of nucleic acids by combining the nucleic acid amplification and detection steps using gel electrophoresis. Hence, it almost eliminates the need for DNA sequencing or Southern blotting for amplicon identification. One of the many versions of PCR is real-time RT-PCR which has become one of the most broadly used gene amplification and expression methods in molecular biology research. Real-time RT-PCR is commonly employed to discover RNA expression levels through the creation of complimentary DNA (cDNA) transcripts from RNA, and it is frequently confused with real-time PCR. Food labelling provides very important information to help both producers and consumers to make informed choices about healthier and safer food. The process that information from a gene is used in the synthesis of a functional gene product is called gene expression. It enables scientists decipher the functions of genes. Food labelling and gene expression are fundamental to studying the relationships between the human genome, nutrition and health in a relatively new specialist field called nutritional genomics. Nutritional genomics is expected to revolutionize the way health professionals and dieticians treat people in the future. Thus, it is anticipated that the focus of nutritional genomics research will in the future, shift to determining the right type of food for an individual based on his or her genomic compatibility and therefore aid in avoiding foods that are an inappropriate match and could potentially impact negatively on the individual's health. This paper reviews the importance and power of real-time PCR application in food labelling and nutritional genomics, types of fluorescent-based chemistry procedures developed for real-time PCR detection, real-time RT-PCR application in gene expression studies and the great potential of combining these technologies for animal molecular genetics research in sheep and fish.