Two US scientists have been awarded the Nobel Prize for Medicine for discovering a fundamental mechanism which regulates the expression of genes, called RNAi (RNA interference). Andrew Fire of the Stanford School of Medicine and Craig Mello of the University of Massachusetts Medical School won a shared £724,337 for their discovery which was published in the journal Nature in 1998.
RNAi, which occurs normally in plants and animals, allows a gene to be specifically 'silenced'. Our genome operates by sending instructions from DNA in the form of mRNA (messenger RNA) for the manufacture of proteins. When RNAi occurs, tiny sections of RNA in complex with other proteins, bind to a gene's mRNA and destroy it before a protein can be produced.
RNAi plays a key role in mobilising the body's natural defence against viruses, and in controlling genes. Scientists can manipulate this process by introducing tailor-made RNAi sequences to deliberately target and block the activity of a specific gene. This helps them determine the gene function and it has the potential to help researchers shut down genes which cause harm to the body. Besides fighting viral infection, it is hoped that the method may be used to combat cancer, endocrine disorders and cardiovascular disease in the future.
The award is among the quickest to be bestowed, just eight years after the research was first published. Nick Hastie, director of the Human Genetics Unit at the Medical Research Council, UK told Nature 'Their findings have led to an enormous scientific revolution, they have opened up a whole new area of biology with great medical application'. The method is now widely used as a genetic tool and is a promising candidate for future therapies.
The Nobel Prize for Chemistry was awarded to Roger Kronberg of Stanford University for his work unravelling the molecular details of transcription (the process of transferring genetic information from DNA to mRNA) in 2001. Kornberg deciphered the structure of RNA polII, an enzyme which helps transfer information form DNA to mRNA. If this process goes wrong it can cause a whole host of diseases from cancer to diabetes. Understanding this process in more depth is vital to developing new treatments for disease.