Duchene muscular dystrophy (DMD) is a genetically transmitted disease characterized by progressive muscle deterioration and eventually premature death. The disease results from a flawed or mutated DMD gene.
The DMD gene is a segment of DNA on the X-chromosome that encodes the information necessary to produce the protein dystrophin. This gene functions in muscle cells and is necessary for their normal structure and function. If the mutated DMD gene could be replaced with a normal copy before too much damage occurs, then the muscle cells should be able to produce dystrophin and be normal. This type of "gene editing" is not a new concept, but the technology to carry it out has been slowly developing in laboratories around the world.
For some time, it has been possible to identify and isolate or synthesize in the laboratory the normal version of many human genes. One of the major problems facing researchers trying to prevent or cure various genetic diseases, has been finding ways to get the normal genes into the right cells and then getting them to function properly. Scientists are hoping that this technology will someday allow doctors to cure or at least diminish the symptoms of genetic diseases currently affecting humans.
Using a new technology called CRISPR/Cab9, scientists were able to cut out the mutant DMD gene in two beagle puppies and replace it with a normal version. Researchers used 1-month-old beagle puppies who had DMD. They injected them with different doses of a virus carrying the gene-editing machinery. Eight weeks later, dystrophin levels had increased in every muscle group examined. It was found that bringing the level up to just 15 percent of normal was enough to relieve some DMD symptoms. All of the muscles studied (except the tongue), showed at least that level of improvement in both dogs.
Obviously, this is only a start, and much more research will be needed before this technique can be tried on humans. However, these results hint of success for this disease, as well as possible success in developing treatments for other genetic disorders affecting humans.