Limb-girdle muscular dystrophy (LGMD) is a general term for a group of diseases that can cause weakness and wasting of muscles in the arms and legs. The muscles that are generally affected are those that are close to the body, such as muscles found in the shoulders, upper arms, pelvic region, and thighs. Symptoms can occur at any age and tend to become progressive although in some cases the symptoms remain mild.
Dr. Bryan Sutton, associate professor of cell physiology and molecular biophysics at Texas Tech Health Sciences Center, has been researching a protein known as dysferlin since 2009 hoping to find a therapy for individuals with limb-girdle muscular dystrophy. According to Doug Albrecht, director of research and therapeutic discover at the Jain Foundation, this form of muscular dystrophy (MD) is very rare. “It occurs in probably two in a million as far as population of the U.S. goes. Before we came along, it was considered an orphan disease. It’s so rare that there wasn’t specific funding.” Albrecht goes on further to say, the disease doesn’t affect life span but rather the quality of life. Generally, this condition strikes individuals in their late teens and early twenties, and these patients begin having weakness in certain muscles, which makes it difficult to walk up and down stairs, and they can become wheelchair bound.
Sutton notes that wheelchair-bound patients generally spend the rest of their lives unable to walk on their own. Sutton and his colleagues are trying to determine how the disease develops and its causes. He is trying to determine what happens at the atomic level of proteins that are believed to be involved with this condition by looking at the structure of the protein dysferlin. At this time, dysferlin is believed to be able to repair tears in muscle. When people exercise, they end up slightly tearing muscle, and dysferlin acts as a temporary “Band-Aid.” If the muscle is badly damaged, the muscle proteins become useless. Sutton’s research involves X-ray crystallography with dysferlin proteins. By shining a highly focused X-ray on the crystallized proteins and watching light diffract, Sutton uses mathematical calculations to determine reaction patterns in dysferlin.