An Overview of Muscular Dystrophy

Muscular Dystrophy is a group of various disorders of the muscular system, mostly involving skeletal muscle in the body. It represents a group of genetic disorders that result in abnormal muscle proteins being formed or absent. This in turn causes muscle dysfunction, weakness, loss of muscle fibers, inflammatory injury, as well as sometimes involvement of other tissues. Of the group, some are rare and some are more common. Some have tremendous disability and rapid decline whereas others have minimal symptoms and very slow almost imperceptible progression. Some present in childhood, while others can wait until late adulthood to declare themselves. Overall, there are nine major types of Muscular Dystrophy disorders.

Despite the variety described, all of the muscular dystrophies share common symptoms to a degree. Dystrophy itself refers to “abnormal growth” which reflects the defective muscle proteins that result in a lack of normal function. While not all of the abnormal gene sites have been identified for all of these disorders, it is suspected that all result in structural deformities of the muscle that prevent it from contracting and relaxing in normal fashion. In essence, a muscle fiber has a very fine tuned system where various ions like calcium, magnesium and potassium flow into and out of muscle cells through their membrane proteins. Any aberrancy in this precise process can result in significant dysfunction and poor health of the muscle fiber and cells.

 While some muscular dystrophies can present as new genetic defects, most are inherited. More than 50,000 Americans are affected by muscular dystrophy making it a significant cause of disability and premature death. Telethons have fortunately brought its awareness to the forefront, and as a result, research monies are available to seek new and better treatments and therapies. For now, therapies are limited, and most are geared at slowing the deterioration of the muscle fibers and minimizing symptoms and limitations. Gene therapy which holds the greatest promise for correcting the root cause is under intense investigation currently. In this approach, tissue that carries normal gene DNA, and subsequently the normal muscle protein product, is transplanted into the recipient allowing a return of at least partial function. For now, this is still investigational.