Imagine being a parent and discovering that your child will not be able to walk at the age of 12 and will not live past the age of 20. This has become a reality for many parents. when they discover that their child suffers from a form of muscular dystrophy. This particular type of muscular dystrophy is called Duchenne muscular dystrophy, which is a genetically inherited disease that is the most common and severe of all muscular dystrophies. It is found in 1 in 3,500 men and is characterized by progressive muscle wasting. It is caused by a lack of dystrophin, a protein found in the cell membrane of muscles. One of the first clinical signs of the disease is that the child starts walking late and is sometimes referred to as a late bloomer. Usually, when the child walks, he waddles and sometimes he walks on tiptoes. We usually notice hypertrophy or enlargement of the muscles, especially in the calves. However, hypertrophy is actually caused by adipose tissue (fat), which replaces muscle tissue. It may make the muscles bigger, but it doesn't make them more useful (Cummings, 213). Another clinical sign of DMD is mild mental retardation or learning disabilities. Although this is not apparent until the child is older, this is a common pattern found in children with DMD. Many studies have been carried out to determine the exact causes of mental retardation. Researchers conducted a study in the early 1990s and found that the protein dystrophin was not only present in muscles but also in the cerebral cortex, cerebellum and hippocampus (Wahl). This led researchers to believe that if muscles lacked dystrophin to cause muscle degeneration, then the brain must also lack dystrophin, which could lead to different learning disabilities that are sometimes found in a person with DMD. . Duchenne muscular dystrophy is an X-linked recessive genetic disorder caused by a deficiency of dystrophin, a protein found in muscle cells. This X-linked disorder is usually only found in men. It has been very rarely seen in women because they have two X chromosomes and the disease is recessive. The reason only males get DMD is because the source of the disease is on the X chromosome of heterozygous females (Cummings, 108). They pass it on to half of their sons and...... middle of paper ......t families with DMD and fund research projects. In conclusion, Duchenne muscular dystrophy is a severe form of muscular dystrophy that causes progressive muscle degeneration. Its main cause is the lack of protein dystrophy necessary for the proper functioning of the muscles. It is difficult for victims and their families because there is no definitive cure and they usually do not live beyond 20 years. Hopefully, in the future, technology will allow researchers to find a 100% cure. effective when used. In the meantime, all DMD victims can do is wait and hope. BibliographyCummings, Michael R. & William S. Klug. Concepts of Genetics 4th ed. New York: Macmillan College Publishing Company, 1994 “Duchenne Muscular Dystrophy,” www.rlc.dcccd.edu/MATHSCI/reynolds/MO/dmd2.html. October 25, 1999. “Stem cells join pipeline in fight against DMD.” » www.mdausa.org/publications/Quest/q66resup.html. December 1999. “Muscular Dystrophy Study.” http://personal.neworld.net/~woliver/news.html. July 1999. Wahl, Margaret “The brain in muscular dystrophy, 1997.