Gene therapy and muscular dystrophies

Abstract

There is a genetic muscle disease in humans called limb-girdle muscular dystrophy (LGMD). In this illness, the affected person has a gene that does not make “sarcoglycan” correctly. Sarcoglycan is a protein in the muscle that helps muscles to function correctly. In their study, which appears in this issue of Neurology ®, Louise Rodino-Klapac and her colleagues (2008;71:240–247) studied a specific gene treatment. They wanted to find out whether it was possible to inject mice with a gene that contained a new recipe for sarcoglycan. The idea behind their research is simple. Sarcoglycan is an important component of the muscle cell, but when it is made incorrectly it causes muscle weakness. Because there is no known treatment for LGMD, researchers have been looking for ways to “fix” the “broken” gene. This study is just one step in the long process that ultimately may result in the first treatment for this genetic illness. It is considered a translational study . Translational studies are critical to the development of medical treatments. The term translational refers to research that bridges the gap between basic research and clinical trials. Basic research often indicates studies that are performed on animals or on cells that are grown in a laboratory. Clinical trials are studies of medical treatment on people. Often there are many steps between basic research studies and clinical trials. However, translational studies are needed to chart the course from animals to humans. In the study, Dr. Rodino-Klapac injected a “correct” copy of the sarcoglycan gene into one of the leg muscles of mice. They allowed the gene to be incorporated into the mouse muscle for either 6 or 12 weeks. After this time, they looked at the muscle to determine whether it was making the “correct” sarcoglycan protein on its own. Using the identical, …