RNA interference: what it is and what it does: A potent gene regulator

RNA interference (RNAi) is a potent and specific way of down-regulating gene expression. It is effective in most multicellular organisms, and every gene in the genome can potentially be targeted, providing that the sequence of the gene is known. It has provided a breakthrough in the study of gene regulation, because the function of a gene can often be deduced by inhibiting its ex-pression. RNAi therefore provides a rapid way of studying the function of known genes in organisms where genetic studies are difficult. Since RNAi is effective in human cells, it is now being used in several ways. These include the elucidation of biochemical and metabolic pathways, validation of potential drug targets, and as a therapeutic in the treatment of disease.