AfterTek

American scientists Andrew Fire and Craig Mello won the 2006 Nobel Prize for medicine. Their discovery of how to switch off genes, a potential way to new treatments for diseases from AIDS to blindness and cancer.

Through experiments with worms, the two showed that a double strand of ribonucleic acid, or RNA, the genetic messenger of the cell, can “silence” targeted genes in a process known as RNA interference (RNAi).RNAi has grown quickly into a hot area of research for pharmaceutical and biotechnology companies, who see it as a promising way of tackling a range of conditions.

The discoveries may lead to methods to stop gene expression in diseases such as cancer, slowing tumor growth. The discovery is already being used in clinical trials for viral diseases, for eye diseases, for cardiovascular metabolic diseases.

But even more importantly, it is being used in every drug industry as a fundamental research tool, RNAi has “invaded” laboratories worldwide.Phillip Sharp of the Whitehead Institute for Biomedical Research in Massachusetts, himself a 1993 Nobel prize winner, has used RNAi to kill HIV, the virus that causes AIDS.

Fire earned his Ph.D. in biology in 1983 at the Massachusetts Institute of Technology and is now a professor of pathology and genetics at Stanford University School of Medicine. Mello has a Harvard doctorate and is a professor of molecular medicine at the University of Massachusetts Medical School.

The Massachusetts school said a number of firms — Novartis AG, Bristol-Myers Squibb, Monsanto Co., GlaxoSmithKline and Pfizer — had licensed RNAi for their research.

Massachusetts-based Alnylam Pharmaceuticals Inc. has used RNAi to block a gene involved in cholesterol metabolism, for example, and this week won a grant from the National Institute of Allergy and Infectious Diseases to use the technology against H5N1 avian influenza.