Imagine being a parent and discovering that your child won’t be able to walk by the age of 12 and won't live past the age of 20. This has become a reality for many parents as they find out that their child has a form of muscular dystrophy. This particular type of muscular dystrophy is referred to as Duchenne Muscular Dystrophy, which is a genetically inherited disorder that is the most common and severe of all muscular dystrophies. It is found in 1 of every 3,500 males and is characterized by progressive muscle wasting. It is caused by the lack of dystrophin, which is a protein found in the cell membrane of muscles.
One early clinical sign of the disease is the child showing a late start in walking and sometimes they are referred to as a late bloomer. Usually when the child walks they have a waddling motion and sometimes they walk up on their toes. Usually, hypertrophy, or enlarging of the muscles, especially in the calves is noticed. However, the hypertrophy is actually caused by adipose (fat) tissue, which replaces the muscle tissue. This may make the muscles larger, but it doesn’t make them any more useful (Cummings, 213). Another clinical sign of DMD is small amounts of mental retardation or learning disabilities. Although this is not apparent until the child is older, it is a common pattern that is found in children with DMD. There have been many studies done to determine what exactly causes the mental retardation. Researchers did a study in the early 1990’s and found that the protein dystrophin was not only found in the muscles but also in the brain’s cortex, cerebellum and hippocampus (Wahl). This has led researchers to believe that if the muscles were lacking the dystrophin to cause the muscle degeneration then the brain must also be lacking the dystrophin, which could lead to different learning disabilities that are sometimes found in an individual with DMD.
Duchenne’s Muscular Dystrophy is an X-linked recessive genetic disorder caused by a deficiency of the protein dystrophin, which is found in muscle cells. This X-linked disorder is usually only found in males. It has very rarely been found in females 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 found on the X chromosome of heterozygous females (Cummings, 108). They pass it on to one half of their sons and...
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...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 the protein dystrophy that is necessary for the muscles to function properly. It is tough for the victims and their families because there is no definite cure and they usually don’t live past the age of 20. Hopefully in the future, technology will enable researchers to be able to find a cure that will be a 100 percent effective when used. Until that time comes, all DMD victims can do is wait and hope.
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Duchenne muscular dystrophy (DMD) is a muscular dystrophy that only occurs in boys. It is caused by the mutation of the DMD gene which is inheritable between families in an X-linked recessive, but it rarely occurs in people from families without a known family history of the condition. Starting from the lower limbs, people with DMD have progressive loss of muscle function and weakness. The DMD gene, which encodes the muscle protein, dystrophin, is the second largest gene. Boy’s muscle with Duchenne muscular dystrophy does not create the dystrophin. 1 in 3500 of the male births are approximately affected by the Duchenne muscular dystrophy.
Symptoms: Up to the age of 1-3 years, affected boys have normal muscles that is they learn to stand and walk later than they are supposed to do and speech may be slow in development. Gowers sign is a sign that can be seen in boys. Hypertrophy of the calf muscles is also a characteristic sign of DMD (Alan E H Emery., 1998). Contractures at the knees and elbows are common and it will lead most boys to use wheelchairs by the age of 10, and end them dead before or at the age of 20. The commonest cause of death is cardiac muscles involvement that will lead to cardiac faliure and subsequentl to respiratory failure (Pryse-Phillips, William E. M. and Murray, T. J., “ A concise textbook Essential Neurology”. 4th ...
It is characterized by normal early growth and development followed by a slowing of development, the loss of purposeful use of the hands, slowed brain and head growth, problems with walking, seizures, and intellectual disability.
The major topic of this experiment was to examine two different crosses between Drosophila fruit flies and to determine how many flies of each phenotype were produced. Phenotype refers to an individual’s appearance, where as genotype refers to an individual’s genes. The basic law of genetics that was examined in this lab was formulated by a man often times called the “father of genetics,” Gregor Mendel. He determined that individuals have two alternate forms of a gene, referred to as two alleles. An individual can me homozygous dominant (two dominant alleles, AA), homozygous recessive, (two recessive alleles, aa), or heterozygous (one dominant and one recessive allele, Aa). There were tow particular crosses that took place in this experiment. The first cross-performed was Ebony Bodies versus Vestigle Wings, where Long wings are dominant over short wings and normal bodies are dominant over black bodies. The other cross that was performed was White versus Wild where red eyes in fruit flies are dominant over white eyes.
At younger age sets in and wastes away muscles in multiple parts of the body making life hard for the affected individuals. This wasting starts at the face and continues to the shoulders where it is more severe. But these are not the only effects Infantile facioscapulohumeral muscular dystrophy has on the individual. Infantile facioscapulohumeral muscular dystrophy also has non-muscular effects. A person diagnosed with this disorder will have vision problems, hearing loss and sometimes seizures.
DMD also known as muscular dystrophy is muscular disease that occurs on young boys around age four to six. Muscular dystrophy is genetically transmitted disease carried from parent to offspring. This disease progressively damages or disturbs skeletal and cardiac muscle functions starting on the lower limbs. Obviously by damaging the muscle, the lower limbs and other muscles affected become very weak. This is ultimately caused by the lack dystrophin, a protein the body produces.
Duchenne muscular dystrophy, also known as DMD, the most common type of muscular dystrophy, is caused by the incorrect information with the gene that generates a protein called dystrophin. The function of this protein is to help muscle cells keep their strength and shape. Without the presence of this protein, muscles begin to deteriorate and a person’s health becomes weaker. Duchenne muscular dystrophy is one of the types that affect boys, and symptoms of the disease begin to show between the ages of two and six. Most children with duchenne muscular dystrophy will require transportation by wheelchair by the age of ten or twelve. Patients with duchenne muscular dystrophy may experience heart c...
It is estimated that 1 out of every 5,600-7,700 boys ages 5-24 have Duchene or Becker muscular dystrophy. (“Data & Statistics,” 2012 April 6) Muscular dystrophy is a group of genetic diseases defined by muscle fibers that are unusually susceptible to damage. There are several different types of muscular dystrophy some of which shorten the affected person’s lifespan. (“Muscular dystrophy: Types and Causes of each form,” n.d.) There is a long history of the disorder but until recently there wasn’t much knowledge of the cause. (“Muscular Dystrophy: Hope through Research,” 16 April 2014) Symptoms are obvious and can be seen as soon as a child starts walking. (“Muscular Dystrophy,” 2012 January 19) Although muscular dystrophy mostly affects boys, girls can get it too. (“Muscular Dystrophy,” 2012 January 19) There is no cure for muscular dystrophy but there are several types of therapy and most types of muscular dystrophy are still fatal. (“Muscular Dystrophy: Hope through Research,” 16 April 2014)
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Some characteristics of DS are: deep folds at the corners of the eyes, hypotonia, short stature, flexible joints, small oral cavity and heart defects (Taylor, Richards, & Brady, 2005). Most individuals with DS have a moderate intellectual disability, although there is a range of disability, from severe to high functioning (IQ above 70). Since DS is a birth defect and not a disease, there are no treatment options. Improvement can be made through physicians, special education, physical therapy, speech therapy, occupational therapy, and psychol...
Symptoms can appear at any age normally between infancy and age six. Normally, the first symptom of duchenne muscular dystrophy is a delay in milestones that normal children have. For example, there may be a delay in when a child with DMD learns to walk, sit or stand by themselves. Children without duchenne muscular dystrophy normally begin to learn to walk at around nine to twelve months, and can walk well around fourteen to fifteen months. Parents and doctors become concerned after sixteen to seventeen months. However, the average age that a child with duchenne muscular dystrophy begins to walk is eighteen months. In muscles in the legs and pelvis, there is progressive weakening and wasting. There is also a little weakness found in the neck, arms, and other upper body muscles, but the weakening in worse in the lower half of the body. Muscles weaken by enlarged muscle tissue being replaced by connective tissue and fat. Muscle fibers then shorten due to the r...
Rantala, M. J., and Roff, D. A. 2006. Analysis of the importance of genotypic variation,
The neurological disorder is generally diagnosed in children aged between six and twelve years, the condition affecting boys three times more often than girls (Hamilton, 2002; Gardner, 2008). Despite the fact that DCD affects roughly 6.4 percent of children, few individuals are familiar with the condition (Hamilton, 2002). In fact, a study by Kirby, Davies, & Bryant (2005) revealed that only 54.3% of teachers and 26.7% of general practitioners could accurately define DCD (p. 124). In response, the condition will be briefly outlined here.
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