RNA expression refers to the process by which genes are transcribed into RNA molecules, which then serve as the templates for protein synthesis. This area of research focuses on studying the levels of various types of RNA molecules within cells, tissues, or organisms, and understanding how changes in RNA expression patterns can impact cellular processes, development, and disease. Researchers may use techniques such as RNA sequencing, microarrays, and quantitative polymerase chain reaction (qPCR) to measure and analyze RNA expression levels. By studying RNA expression, scientists can gain insight into the regulation of gene expression, identify biomarkers for disease, and potentially discover new drug targets. Additionally, RNA expression analysis can provide valuable information about the function and activity of different cell types within a biological system.