X-Message-Number: 15819 From: "Mark Plus" <> Subject: "Genetic Tinkering Is Found to Extend Roundworms' Lives" Date: Wed, 07 Mar 2001 22:34:45 -0800 From: http://www.nytimes.com/2001/03/08/health/08WORM.html?pagewanted=all March 8, 2001 Genetic Tinkering Is Found to Extend Roundworms' Lives By REUTERS Scientists say they have extended the life span of an animal though just a worm by tinkering with its genetic makeup. The findings could one day lead to drugs that help humans live longer, researchers said. Roundworms normally die at about two weeks old, but after researchers at M.I.T. gave the tiny creatures extra copies of chromosomes containing a specific gene, they lived up to three weeks, or 50 percent longer. The researchers, led by Leonard Guarente and Heidi Tissenbaum, report their results today in the journal Nature. Scientists have known for decades that the key to extending life spans in yeast, worms, mice and possibly primates is restricting calories to a fraction of their normal levels. Based on his earlier studies with yeast, Dr. Guarente has suggested that this effect occurred because of the interaction between metabolism and a gene that shuts down other genes. He has shown that yeast with two copies of this SIR2 gene lived longer and that yeast without it had a shorter life span. In the new study, Dr. Guarente and colleagues showed that a similar gene, SIR2.1, had the same effect on a higher organism, the roundworm. The result suggests that similar genes could be linked to aging in all organisms, including humans, they said. Scientists have known for decades that the key to extending life spans in yeast, worms, mice and possibly primates is restricting calories to a fraction of normal levels. "The big question is the mechanism by which that works. How does that confer longevity? That's what we are trying to get at here. Our proposal is that this could be at least part of the answer to that question," Dr. Guarente said. In the yeast studies, the scientists showed that the effect of SIR2 on aging is linked to nutrition and metabolic rate. They suspect the same is true with worms. _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=15819