RNA interference, RNAi
RNA interference, RNAiA process that blocks, or enhances, gene expression by altering RNA. RNA interference occurs naturally against viruses and to control gene activity and has attracted much attention for its potential as a therapeutic process. It involves modification of MESSENGER RNA using small RNA molecule fragments (siRNA) that matche part of the sequence of the target gene. In the search for effective artificial RNA interference methods, arbitrary short sequences have often been found to fail because they are ‘decoyed’ by other genes in the genome. MicroRNAs were initially shown to be important in the development of flower structure but are now recognized as important in animal genetics. RNAi has been extensively used in genetic research to determine the function of genes. In 2006 RNAi was used successfully in a primate to cut LDL cholesterol by 90 percent. It has also been shown to be capable of turning on genes.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005