A great deal of good medicine could be accomplished if we just had the option of adjusting our DNA - safely making small edits on an ongoing basis to genes and their expression in specific tissues. Shifting the controlling genetics of your metabolism into the most optimal configuration for healthy life span, based on what is learned from calorie restriction studies and other research, would be one of many options. Sorting out some of the known problems in the aging immune system would be another. There are many more opportunities for improvement along the same lines, but the full genetics of aging are far from clear. Studies performed to date show that many genes - hundreds for any given organ in the body - change their function as life progresses, but it is not known how much of this is relevant or interesting, programmed aging, a reaction to age-related cellular damage - or the direct result of age-related mutational damage to DNA. Even in this last case there are still ways forward based on the alteration of DNA: editing can be a method for repairing damaged DNA as well.
Scientists are in the early stages of writing changes to DNA; tools such as viral gene therapy and protofection are blunt hammers in comparison to the state of the art yet to come, and even these are still in trials and the laboratory. Matters are advancing rapidly, however, as recent news illustrates:
In a study to be published in the January 2006 issue of Nature Biotechnology, researchers led by a team of scientists at Memorial Sloan-Kettering Cancer Center have devised a novel strategy that uses stem cell-based gene therapy and RNA interference to genetically reverse sickle cell disease (SCD) in human cells.
Sangamo BioSciences Inc. said its technology for "editing" DNA has allowed it to develop a new therapy that can make cells resistant to HIV infection. The technology disrupts the so-called CCR5 gene that provides an entryway for HIV into T-cells, the infection fighting cells of the immune system.
A new method has been developed for switching genes on and off that could greatly improve gene therapy. ... Until now, researchers working to develop successful gene therapy for diseases such as Parkinson's have hit roadblocks such as toxic side-effects from over-expression of the therapeutic gene, and adverse events caused by immune system reactions to the viral delivery systems currently used to deliver the therapeutic genes. Now, we've engineered a genetic switch in a novel gene transfer vector that will overcome those barriers and set the stage to allow the next phase of research to occur