Genetic Disorders: Muscular Dystrophy

Muscular dystrophy is a degenerating disease, in which the skeletal muscles degenerate, lose their strength, and cause increasing disability and deformity. Muscles attached to the bones through tendons are responsible for movement in the human body, however, in muscular dystrophy the muscles become progressively weak. As the muscle fibers

Duchenne muscular dystrophy was first discovered by Guillaume Benjamin Amand Duchenne in the 1860’s, but due to lack of medical knowledge little was known until the 1980’s. It was in 1986 that researchers that were supported by the MDA, muscular dystrophy association, identified the particular X-chromosome that leads to DMD, Duchenne muscular dystrophy. Dystrophin is the protein that is associated with the gene and was named in 1987.The DMD gene is the second largest gene to date, and it produces dystrophin.(Genome, 2013) Lack of the protein Dystrophin in the muscle cells causes them to weaken and become fragile. (MDA, 2015). DMD is an inherited disorder, but there are rare cases where it can spontaneously appear in a child with no previous family history due to a random mutation in moms X-chromosome. DMD is a gender specific disease that only appears in males.

Credibility Statement: According to the "Muscular Dystrophies" by Harvey B.Sarnat in Nelson Textbook of Pediatrics, 20th Ed 2016, "A muscular dystrophy is distinguished from all other neuromuscular diseases by 4 obligatory criteria: It is a primary myopathy, it has a genetic basis,

Duchenne Muscular Dystrophy is a disease which causes skeletal muscle to waste away, this wasting of muscle is caused by a mutation of the dystrophin gene (Meregalli et al., 2013, p. 4251).

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

Genetics is a key factor in potentially developing a form of muscular dystrophy, as it is caused by a gene that protects muscle fibers suddenly becoming defective. However, this particular genetic mutation can abruptly occur while an embryo is still developing in the egg of the mother. Muscular dystrophy can occur in an individual of any age, sex, or race. The most common form of MD diagnosed, Dechenne, is most often found in males of a youg age. However, family history of the disease is the biggest risk factor associated with developing it.

Duchenne Muscular Dystrophy (also referred to as DMD) is a type of muscular dystrophy that weakens the muscles that we need to support our body, body weight, to stand, and to move around. It also can cause you to have scoliosis. Some of the main causes for DMD are genetic disorders, mutations, and DMD has to be passed down throughout everyone in that family for generations. The symptoms you can have if you have DMD are weak muscles, lack of strength, and difficulty walking. DMD is a negative mutation because it affects your muscles horribly bad that you can get a disability of walking and even moving. You need to tell your doctor immediately if you experience any symptoms. If you don't tell your doctor, you may find yourself in a very difficult situation where you can't get up or can't get something you need. When you do talk to your doctor, you will have an advantage of getting the help you need.

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

When looking at a potential therapy or cure, it is important to recognize exactly how the disease affects the body. Duchenne Muscular Dystrophy (DMD) is one of the most severe myopathies, or muscle diseases (Cacchiarelli et al). To be diagnosed with DMD, a patient must have a mutation in the dystrophin gene present (Muscular Dystrophy Association). Moreover, that mutation in the gene is what causes the lack of dystrophin synthesis. Dystrophin is protein in the body that keeps the muscles intact (Muscular Dystrophy Association). Therefore, a lack of dystrophin causes the muscles to deteriorate; which is identified as dystrophy. When the body lacks strong healthy muscle, it does not only become weak; the body itself begins to shut down. Our organs depend on the muscles that allow us to walk, eat, and breathe to provide energy, nutrients, and oxygen. For this reason, DMD eventually leads to a short life.

Myotonic dystrophy (DM) is a disorder that affects multiple systems in the body. The disease is broken down into two categories, myotonic dystrophy I & II. Myotonic dystrophy can be responsible for deterioration of smooth and skeletal muscle, central nervous system, endocrine, cardiac, and ocular systems. Myotonic dystrophy can contrast from mild to severe, and has “been categorized into three somewhat overlapping phenotypes: mild, classic, and congenital” (Bird et al., 1999). Myotonic dystrophy is a multisystem disease damaging to the muscles, heart, brain, eyes and other organs. Myotonia is defined by the stiffness and tightness of the muscles causing some muscles to stay in the contracted position much longer than

There are more than twenty subtypes of LGMD, each is classified according to the genetic flaws that appear to cause them. Fifteen genes that lead to the production of muscle proteins have been identified as definite causes of LGMD when they are flawed. According to the Muscular Dystrophy Association, “Type 1 LGMDs are dominantly inherited, requiring only one mutation for symptoms to result. Type 2 LGMDs are recessively inherited, requiring two mutations — one from each parent — for symptoms to appear. Sometimes, LGMDs are referred to by their names, not their numbers, and some types have not been assigned numbers.” When one of these genes is faulty and protein problems arise, muscle cells and fibers do not function properly. The muscles then

Muscular dystrophy is defined as a disease that the causes a loss of muscle mass and progressive weakness. Muscular dystrophy is not and infectious disease, but one that is passed on through abnormal gene mutations that prevent the production of the proteins that are needed to form healthy muscles. Muscular dystrophy is not a single disease, but a group of diseases. There are multiple types of muscular dystrophy, such as Duchenne muscular dystrophy, which is the most common form in male children. Other forms of muscular dystrophy include Myotonic, Becker, Limb-Girdle, Facioscapulohumeral, Congenital, Oculopharyngeal, Distal and Emery-Dreifuss. Muscular dystrophy can materialize in anyone from infants to seniors.

SMA belongs to a group of illnesses known as Muscular Dystrophies which are inherited genetic diseases that cause progressive degeneration of groups of muscles (Waugh et al, 2014). There are four main types of SMA which are categorised according to the age at which the symptoms develop. Type I is the most severe and develops in babies less than six months old (muscular-dystrophy, 2014. Online), it is thought to be the most common form of the disease (NHS, 2013. Online). The gene that causes SMA is passed from parents to children but can only affect a child if both parents carry a defective gene (smasupport, ND. Online).

Muscular dystrophy is defined as, according to Mayo Clinic, “ One of a group of genetic

While muscles are the driving force of the movement of the body, they can also become infected, damaged, and negatively affected by many different illnesses and genetic defects. An example of an inherited disease that affects muscular function is congenital myasthenic syndrome. According to the Muscular Dystrophy Association, congenital myasthenic syndrome causes the weakening and reduced function of muscles (MDA 2015). Life with CMS can be extremely difficult, as muscular function and contraction controls many parts of movement, including respiration. According to the Genetics Home Reference of the U.S. National Library of Medicine, the effects of CMS can be varied depending on each individual case; some individuals may only encounter weakening