Duchenne Muscular Dystrophy Bibliography
Duchenne Muscular Dystrophy Questions

Duchenne Muscular Dystrophy
By: Chloe W, Molly G, Frankie G, and Mackenzie M

Characteristics of this disease

Duchenne muscular dystrophy affects 1 in every 3500 male births. Women are able to carry the gene for this disorder but do not show it. They have a 50% chance of passing it their sons. Symptoms of this genetic disease start to appear between the ages of 2 and 6. Muscular dystrophy is muscle weakness that progresses over time. Early signs include frequent falling, difficulty getting up from a seated position. This is due to weak stomach muscles. Calf muscles also become large, and the person loses the ability to lift his/her knees. The child may also experience fatigue and may have mental retardation. Unlike the muscles this does not progress over time. Many have scoliosis which affects their spine. Most children with this disorder have weak motor skills like trouble running and jumping. As the child ages the symptoms become more noticeable. The leg and pelvis muscles start to weaken first and by age 11 the child loses the ability to walk. The arm and neck muscles are also affected but less severely. Death usually occurs before the child reaches the age of 20. The main cause of death is respiratory failure or pulmonary infections.

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Mutation Caused

Duchenne muscular dystrophy is caused by a defected gene in male chromosomes, (the X chromosome). The people affected by this disease have a mutated DMD gene, which is found on the short arm of the X chromosome at a certain position. DMD occurs when a specific gene on the X chromosome does not make the protein dystrophin. Dystrophin is a protein that helps the muscles hold their shapes, and function properly. A lot of people can carry Duchenne muscular dystrophy but it’s not until a mutation arises that the disease is shown. As one of the largest human genes known, DMD compasses over two million base pairs of DNA. Even though the disease does not usually effect women, themselves and their children still have the probability of being carriers; there is a 50% chance of the disease being transferred to their children. Duchenne muscular dystrophy and muscle degeneration go hand in hand.

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How is Duchenne Muscular Dystrophy inherited?

DMD is inherited through hereditary. Males inherit the disease through their mothers who actually carry the disease without it affecting them. It is passed from a mutated X chromosome, which is why it is only inherited by boys. Girls require two X chromosomes which means if only one is defected they will not being affected by the disease, just carry it. Males on the other hand are affected because they only have one X chromosome. The dystrophy can only be inherited from the mother because the father can't pass down X chromosomes. There is a 50% probability mothers will give the disease to their sons.

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Scientists have not found a cure for Duchenne Muscular Dystrophy yet. However, Doctors recommend exercise and physical therapy to prevent muscles from tightening up and to increase mobility. Doctors also recommend joining a support group to help decrease stress levels and to meet with people who are in the same situation as you. Also, steroids are used on people how have DMD to help to slow down the effects and to increase life span. Doctors have found that young boys with DMD who took steroids were able to walk by themselves for three years longer than those with DMD who did not take steroids. Because Scoliosis is often contracted by people who have DMD, doctors recommend exercising the back to keep it from curving and limiting mobility. To help prevent the legs from curving, patients with DMD use braces until muscles become too weak to walk. Also, patients with DMD should take calcium and vitamin D supplements daily to make sure their bones stay strong and healthy. In the future, doctors are predicting that therapy for genes may be used for patients with DMD, but for now there are no ways to prevent this disease.

As patients with DMD grow older, the slight curve in their backs become more severe.
As patients with DMD grow older, the slight curve in their backs become more severe.

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