Gene Expression Analysis and Real-Time PCR (qPCR) Information

Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as rRNA genes or tRNA genes, the product is a structural or housekeeping RNA. In addition, small non-coding RNAs (miRNAs, piRNA) and various classes of long non-coding RNAs are involved in a variety of regulatory functions.

When studying gene expression with real-time polymerase chain reaction (PCR), scientists usually investigate changes—increases or decreases—in the expression of a particular gene or set of genes by measuring the abundance of the gene-specific transcript. The investigation monitors the response of a gene to treatment with a compound or drug of interest, under a defined set of conditions. Gene expression studies can also involve looking at profiles or patterns of expression of several genes.

Gene expression profiling simultaneously compares the expression levels of multiple genes between two or more samples. This analysis can help scientists identify the molecular basis of phenotypic differences and select gene expression targets for in-depth study. Gene expression profiling provides valuable insight into the role of differential gene expression in normal biological and disease processes.