Duchenne Muscular Dystrophy Research Paper

Muscular dystrophy is an inherited disease that was discovered in 1861, by Guillaume B.A. Duchenne. Muscular dystrophy is a group of heredity disorders characterized by rapidly-worsening muscle weakness. The trait for muscular dystrophy may be transmitted as an autosomal dominant which means a disorder that has two copies of an abnormal gene that must be present in order for the disease or trait to develop. In this case, if some original carrier of the disease had children, the children would have a fifty-fifty chance of inheriting the disease. It is also carried as an autosomal recessive trait, in which case the offspring of the original carrier would have a very small chance of

Duchenne muscular Dystrophy (DMD) is the most common out of nine types of muscular dystrophy. This genetic disorder causes progressive muscular weakness, and deterioration due to the lack of a protein called Dystrophin. This protein keeps the muscles in tack, so when it's missing, the muscles slowly break down. (MDA, 2015)

Ben has Duchenne Muscular Dystrophy (DMD). DMD is a degenerative disease of the muscles. When someone has this disease their muscles do not produce enough dystrophin to stay together. This causes the muscles to deteriorate over time. With proper care, the rate of muscle degradation can be slowed down. Duchenne muscular dystrophy is a genetic disorder characterized by progressive muscle degeneration and weakness. Muscle weakness can start as early as age three. It first affects the hips, pelvic area, thighs, and shoulders. This disease is still fatal and will be until further studies and research are done to find ways to cure this disease.

Duchenne Muscular Dystrophy shows its first symptoms in a boy’s early childhood, usually in preschool. The weaknesses of the skeletal and muscular systems start in the pelvis and progress

Duchenne Muscular Dystrophy is an X-linked genetic disorder caused by a genetic mutation in the dystrophin gene. The disorder is recessive, therefore males are more at risk for displaying the mutation than women. However, women can be carriers and have mild effects. Duchenne Muscular Dystrophy affects the neuromuscular systems, which can result in deterioration of muscles and eventually death.1 The disorder usually presents itself in early childhood, and can affect the respiratory and cardio systems. The disease can cause spinal problems, respiratory problems, intellectual disability, and cardiac disease which is the main cause of death.4

On very rare occasions when DNA studies do not present a clear picture a muscle biopsy may be required. A small piece of muscle tissue is taken with a needle, usually from the thigh. Using special staining techniques in the laboratory the muscle tissue is examined microscopically for dystrophin protein. In DMD, dystrophin is completely absent while in the related disorder Becker muscular dystrophy some dystrophin is present. Therefore, the muscle biopsy test is important in providing a definite diagnosis when DNA tests are inconclusive.

Therefore, individuals that suffer from DMD will usually die in their early 20s, due to infection, heart and/or respiratory difficulties (Blake et al., 2002). During 1961-1982, data was collected on 473 Dutch Duchenne muscular dystrophy patients. By studying this data, it was shown that the median survival was 19.4 years for patients that have already passed the age of 10 years old. About 23.6% of individuals survived 23.3 years at the minimum. On average, patients died 7.9 years after becoming immobile (Essen et al.) DMD can be detected shortly after birth by examining the amount of serum creatine kinase (CK) activity within the infant. Although, diagnosis is usually made during 3 to 8 years (Jennekens FG, et al. 1991). The symptoms of Muscular Dystrophy typically appear between the ages of two and three. The symptoms include falling frequently, increased clumsiness, walking on the toes, stiffness and weakness in the muscles, mental impairment, learning disabilities and

Duchenne’s muscular dystrophy (DMD) is a progressive genetic disorder that leads to muscle atrophy and eventually death. Diagnosing DMD consists of blood tests, genetic testing, and muscle biopsies. Signs and symptoms begin presenting in toddlers with DMD and progressively worsen throughout life. There is no cure for DMD, and will cause terminal cardiopulmonary complications. Medical interventions consist of corticosteroid treatment, respiratory management, cardiac management, psychological management, and physical therapy interventions.

Duchenne Muscular Dystrophy was first discovered in the 1860s by a French neurologist which went by the name of Guillaume Benjamin Amand Duchenne de Boulogne. Guillaume was the first to consider multiple types of muscular atrophy and paralysis which were caused by nerve disorders. He discovered that muscular atrophy was caused by a degeneration of the dorsal columns of the spinal cord. During the 1860s, Duchenne de Boulogne assessed and described the progressive muscle weakness within 13 boys. Using an instrument that Guillaume, himself had developed, he was able to remove portions of tissue found deep within the body which assisted with the discovery of biopsy practices.

Currently, there are 9 major forms of muscular dystrophy which include: Myotonic, Becker, Limb-girdle, Facioscapulohumeral, Congenital, Oculopharyngeal, Distal, Emery-Dreifuss, and Duchenne muscular dystrophy (Mayo Clinic, 2014). For the purpose of this paper, the cause, as well as the impact of Duchenne muscular dystrophy on development, will be discussed.

CRISPR Cas-9 is a system that changes genes and shows a further promise for treatment for Duchenne Muscular Dystrophy (DMD). Doing this will hopefully avoid ethical dilemmas. DMD effects nearly 1 in 5,600-7,700 people between the ages of 5 and 24 for males in the U. S. CRISPR stands for “Clustered Regularly Interspaced Short Palindromic Repeats”. These are DNA segments found in microorganisms that repeat itself in open spaces. CRISPR attacks any virus that comes into your body and cuts the strand of virus on the DNA out. Researchers have tried to cure DMD in mice by getting therapy through the back of the eye, one of the ways CRISPR therapy works, which seems to work best.

Duchenne muscular dystrophy (DMD) is caused by a mutated gene in the X chromosome. This flawed genes is passed on by the mother. However, most carrier of the gene do not show signs or symptoms of the disease. The The flawed gene causes the improper production of the protein dystrophin which is accompanied by “defective dystrophin-glycoprotein complex (DGC) in the sarcolemma and leads to progressive muscle degeneration” (Nakamura & Takeda, 2011). The Dystrophin protein is vital in providing a muscle integrity. Therefore, the absence of dystrophin production can lead to muscled atrophy.

Duchenne Muscular Dystrophy is one of the most severe yet common cases of Muscular Dystrophy that occurs mainly in boys of younger age. Guillaume Benjamin Amand Duchenne, who was a French neurologist, was the first to discover this disorder in the 1860s (Emery, 2008, pp. 25). This disease is an X-linked disorder which affects the skeletal system, and causes rapid muscular weakness and heart muscle problems. It’s stated that 1 out of every 3,600 males will be diagnosed with Duchenne Muscular Dystrophy (Bushby, 2009, pp.1). According to the Muscular Dystrophy Association, symptoms usually begin to show between the ages of 3 to 5 years old. (pp. 1) Some of the symptoms may include delayed in walking, regularly falling, learning difficulties,

There are two ways to diagnose myotonic dystrophy; with molecular genetic testing or with non-genetic testing. Genetic testing is when the test for the amount of CTG repeats in the DMPK gene. Normal alleles have 5-34 repeats. Premutation alleles have 35-49 repeats, this means that the patients does not show symptoms but their children are at increased risk of inheriting a larger repeat size. Full penetrance alleles have more than 50 repeats. Non-genetic testing includes an electromyography (EMG), if a patient has myotonic dystrophy the doctors will see myotonic discharges and myopathic-appearing motor units. They can also test for serum CK concentration, which is elevated in affected patients. Another test they can do is a muscle biopsy, they would see rows of internal nuclei, ring fibers, sarcoplasmic masses, type 1 fiber predominance and atrophy, fibrosis and fatty infiltration and an increased number of intrafusal muscle fibers in affected

Muscular dystrophy can be diagnosed with a physical exam and diagnostic testing completed by the child’s pediatrician. Additional information that will be obtained during the examination will be family history, pregnancy history, and birth history. Diagnostic studies for muscular dystrophy include muscle serum enzymes (especially creatine kinase), electromyogram (EMG) testing, muscle fiber biopsy, electrocardiogram abnormalities reflective of cardiomyopathy, and genetic pedigree (Lewis, 2011). Duchenne muscular dystrophy is caused by the lack of dystrophin. A muscle biopsy can be done to confirm a diagnosis of muscle dystrophy. The biopsy will show evidence of significant fat and connective tissue deposits, deterioration and necrosis of muscle fibers, and a lack of the muscle