New submitter TheNinjaCoder writes: A new type of gene therapy is showing promise in reversing the aging process. The scientists are not claiming that aging can be eliminated, but say that in the foreseeable future treatments designed to slow the process could increase life expectancy. The Guardian explains the scientists' experiment in its report: "The rejuvenating treatment given to the mice was based on a technique that has previously been used to 'rewind' adult cells, such as skin cells, back into powerful stem cells, very similar to those seen in embryos. These so-called induced pluripotent stem (iPS) cells have the ability to multiply and turn into any cell type in the body and are already being tested in trials designed to provide 'spare parts' for patients. The treatment involved intermittently switching on the same four genes that are used to turn skin cells into iPS cells. The mice were genetically engineered in such a way that the four genes could be artificially switched on when the mice were exposed to a chemical in their drinking water. The scientists tested the treatment in mice with a genetic disorder, called progeria, which is linked to accelerated aging, DNA damage, organ dysfunction and dramatically shortened lifespan. After six weeks of treatment, the mice looked visibly younger, skin and muscle tone improved and they lived 30% longer. When the same genes were targeted in cells, DNA damage was reduced and the function of the cellular batteries, called the mitochondria, improved. Crucially, the mice did not have an increased cancer risk, suggesting that the treatment had successfully rewound cells without turning them all the way back into stem cells, which can proliferate uncontrollably in the body." The study has been published in the journal Cell.