Craig Mello

In 1998, an article by Dr. Craig Mello, published in the journal Nature, ignited a revolution in biomedical research. The discovery swept through laboratories around the world, changing the way biomedical researchers work in fields from medicine to agriculture. Science had already identified the role of the messenger RNA (mRNA) molecule in conveying genetic information from the DNA molecule to the cells of living things, but when scientists attempted to manipulate this communication for experimental purposes, they experienced baffling and contradictory results. Dr. Mello of the University of Massachusetts Medical School, in collaboration with scientists from the Carnegie Institution, devised an ingenious experiment, with the genes of the nematode worm. He bound one RNA molecule to another, constructed in its mirror image. This double-stranded molecule, injected into the cells of the worm, effectively silenced the gene corresponding to the original RNA molecule. Mello and his colleagues soon found that this process, which they dubbed "RNA interference" (RNAi), occurs naturally in all living things, from plants and fungi to animals and human beings. It plays a role in the differentiation of cells, in the suppression of viruses, and probably in the mechanisms of inheritance, variation and the evolution of species. The discovery of RNAi unveils a new vista of possibilities for the study and treatment of viral infections, inherited ailments and immune disorders, including diabetes, cancer, ALS and HIV-AIDS. Craig Mello addressed the student delegates at the 2007 Achievement Summit in Washington, D.C., six months after receiving the 2006 Nobel Prize in Medicine.