Cutting one gene makes flies live six times longer, researchers find

<body leftmargin="0" bgcolor="#000060" text="#FFFFFF" link="#FFFF00" vlink="#FF9900"> <table border="0" cellpadding="0" cellspacing="0" width="95%" height="1"> <tr> <center> <td valign="top" width="33%" height="33"> <p class="MsoNormal"><b><font face="Arial" size="5">Cutting one gene makes files live six times longer, researchers find</font></b></p> <p class="MsoNormal"><font size="1" face="Arial">March 30</font><font face="Arial"><font size="1">, 2005<br> Special to World Science<br> </font><br> </font><font face="Arial" size="2"><b>An experiment has resulted in one of the longest recorded life-span extensions in any organism and opened a new door for anti-aging research in humans, researchers say.<br> <br> Scientists have known for several years that an extra copy of a gene called SIR2 can promote longevity in yeast, worms and fruit flies. <br> <br> But now, scientists at the University of Southern California say removing the gene gives even better results: it makes fruit flies live up to six times longer than normal.<br> <br> Researchers said they got the most dramatic improvement was found when they combined the gene removal with an extremely low-calorie diet and/or a mutation in one or two genes, called RAS2 and SCH9. <br> <br> Experiments with human cells gave results consistent with these findings, the researchers said.<br> <br> The researchers wrote a paper describing the fruit fly experiments to appear in the Nov. 18 edition of the research journal Cell.<br> <br> Since all mammals share key aging-related genes, the paper points to a new direction for human anti-aging research. <br> <br> The university’s Valter Longo, lead author of the paper, suggests that removing SIR2 may let an organism more easily go into a an extreme survival mode characterized by the absence of reproduction, improved DNA repair and increased protection against stress to its cells. <br> <br> The long-lived organisms in Longo’s experiment showed extraordinary resilience under stress, he said. “We hit them with oxidants, we hit them with heat,” he remarked. Oxidants are a type of oxygen-containing chemical that damage cells. <br> <br> Longo predicted that as molecular geneticists master the levers of aging, they will be able to design drugs that coax the body into entering chosen aspects of a starvation-response mode, such as stress resistance, even when food is plentiful. <br> <br> If enough food is available, an organism might be programmed both to reproduce normally and to maximize its survival systems. <br> <br> Longo urged caution in extrapolating the result to humans. <br> <br> “We have been very successful with simple organisms,” he said. “Naturally, mammals are complex, and it will be a great challenge to get major life-span extension.”</b></font></p> <p class="MsoNormal"><b><font face="Arial" size="2">* * *</font></p> <p><font face="Arial" size="2" color="#FFFFFF">Send us a <a href="mailto:editor@world-science.net">comment</a> on this story, or <a href="mailto:?Body=http://www.world-science.net/othernews/051117_lifespanfrm.htm">send it to a friend</a></font></p> <p></b></p> </center></td> </tr> </table> </body>