Skip to main content
HHS Logo U.S. Department of Health & Human Services Divider arrow NIH logo National Institutes of Health Alt desc
RNA Interference

About RNAi

Small interfering RNA (siRNA) molecules are pieces of RNA that block the activity of genes through a natural process called RNA interference (RNAi). This process has emerged as a powerful tool used in thousands of labs worldwide to understand gene function. Because each siRNA molecule can block a different gene, RNAi can tell scientists about the role of any gene in maintaining health or causing disease.

In tests called genome-wide RNAi screens, scientists use robots to introduce siRNAs into human cells to block the activity of each gene, one at a time. This process can produce a complete list of all genes involved in a particular biological function or disease process, an invaluable step in identifying potential drug targets. Scientists also can use these techniques to understand how genes affect the effectiveness of drugs. Learn more about the goals of the RNAi program.

Historically, a lack of methods to properly interpret the results of genome-wide screens, a lack of collaborative expertise to perform RNAi experiments, and the absence of comprehensive RNAi data in public databases for researchers to reference all have limited RNAi’s usefulness. To address these problems, NCATS operates a state-of-the-art RNAi screening facility open to NIH investigators. Learn more about how the RNAi program works.