Americans Win Medicine Nobels for 'Silencing' Genes Americans Andrew Z. Fire and Craig C. Mello win the Nobel Prize in Physiology or Medicine for discovering "RNA interference," a way organisms turn off individual genes. The discovery is considered by many scientists to be a breakthrough in modern biology.
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Americans Win Medicine Nobels for 'Silencing' Genes

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Americans Win Medicine Nobels for 'Silencing' Genes

Americans Win Medicine Nobels for 'Silencing' Genes

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This is All Things Considered, from NPR News. I'm Melissa Block.


And I'm Michele Norris.

Today, the Nobel Prize for Physiology or Medicine was awarded to two relatively young American scientists who have given biologists an important new research tool. Many believe it's only a matter of time before their discovery leads to new kinds of drugs to fight ailments as diverse as hepatitis, cancer and Huntington's disease.

NPR's Richard Knox reports.

RICHARD KNOX: The two winners are Andrew Fire of Stanford and Craig Mello, a Howard Hughes Medical institute researcher at the University of Massachusetts Medical school. Early this morning, they got the call from Stockholm saying they'll share the $1.4 million prize. They won for discovering something called RNA interference. William Hahn of the Broad Institute at MIT says, it allows scientists to turn genes off one at a time.

Dr. WILLIAM HAHN (MIT): It's a lot like going to the fuse box at home and flipping the switches to see which lights are controlled by which circuit.

KNOX: In only eight years since Fire and Mello published their main findings, Hahn says RNA interference has been taken up by biologists everywhere.

Dr. HAHN: It has changed the way all of us do science everyday. You cannot go to any lecture or have any discussion in biological science without talking or using RNA interference. And because of that, I think, it's very clear that this is a tool that has already transformed biology and it's going to be used further to foreseeable future.

KNOX: Scientists think that RNA interference first evolved eons ago to defend cells against viruses. Many viruses, such as influenza, are made up of two twisted strands of genetic material called RNA. Fire says a cell, any cell, just hates viruses made from double strands of RNA.

Dr. HAHN: So there. If we don't want this stuff around and, not only does it get rid of double stranded RNA, it gets rid of anything that looks like it.

KNOX: Cells learned how to turn off the viral genes. Fire and Mello won the prize for demonstrating that RNA interference gives biologists the ability to turn off any gene they want to. Here's Craig Mello.

Dr. CRAIG MELLO (Noble Prize winner): RNA Interference is proven to be a quite reliable mechanism for turning genes off in a whole variety of different plants and animals.

KNOX: And why would scientists want to do that? The reasons are virtually limitless. Some researchers turn off genes one by one to see how they function in aging. Some groups are using RNA interference to find out which genes are important in causing cancer. This spring, one group showed they could reverse heart disease in mice by silencing a gene that makes bad cholesterol. Others are interested in applying RNA Interference to neurological disorders like ALS and infections like HIV.

Dr. MELLO: It's accelerating the phase of discovery in molecular medical research, because we can learn about the function of each individual gene. And that's allowing researchers all over the world to begin linking particular genes with a variety of different diseases.

KNOX: Drugs that use RNA interference are only beginning to be tested in humans. One of the first small studies involves macular degeneration in eye disease. A lot of hurdles remain. Researchers have to figure out how to usher their custom built RNA molecules to the right location without being broken down first. They have to demonstrate safety. A therapeutic effect needs to be long lasting.

But the Nobel Committee is betting that RNA interference has a bright future. It's unusual, though not unheard of, for the committee to honor scientists who are so young. Fire is 47, Mello is 45. Mello laughs about his mother's reaction to that.

Dr. MELLO: She said, you're so young. Can you win it again?

KNOX: That sets a high standard. But Mello and Fire say they're not done. They have a lot of work to do, following up leads from their Nobel Prize winning work.

Richard Knox, NPR News, Boston.

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