Duchenne muscular dystrophy (DMD) is a form of muscular dystrophy described by the French neurologist Guillaume Benjamin Amand Duchenne in the 1860s. Some claim, with good documentation, that the English physician Edward Meryon was actually the first to accurately describe the disorder, but history has favored Duchenne's name in association with this form of muscle disease.
The term dystrophy comes from the Greek words dys, meaning abnormal or faulty, and trophe, meaning food or nourishment. As doctors observed muscles weaken and waste away, they guessed that there was some kind of nourishment the muscles weren't getting. The term is actually somewhat incorrect, since we now know there is no missing muscle nutrient in any known form of muscular dystrophy, but it was a logical enough supposition many years ago, and the term has remained with us.
Muscular dystrophies are defined nowadays as a group of genetic disorders characterized by progressive muscle wasting and weakness and characteristic microscopic changes in the muscle. Muscular dystrophies are part of a larger group of disorders known as myopathies, meaning simply that something is wrong with the muscle. (Mys is the Greek word for muscle, and pathos is the Greek word for disease.) The primary problem in myopathies, including muscular dystrophies, is in the muscles themselves -- not the nerves that control them, the blood vessels that supply them or the bones that support them. This distinguishes dystrophies from other conditions that affect muscles.
For a long time -- in fact, until the 1980s -- there was little known about the cause of Duchenne muscular dystrophy, or any other kind of muscular dystrophy. Until the advances in cell and molecular biology of the 1970s and 1980s, it wasn't even clear whether the problem was really in the muscle or whether the muscles weakened and wasted because they lost their nerve or blood supply.
Then, in 1986, following rapid advances in molecular biology and laboratory techniques, MDA-supported researchers identified the gene that, when flawed -- a problem known as a mutation -- causes DMD. In 1987, the protein associated with this gene was identified and named dystrophin.
Thus, the first real clues toward understanding the disorder were found, setting the stage for all subsequent research.
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