It is generally considered less serious than other forms of muscular dystrophy. This condition gets its name from the areas of the body that are affected most often — the muscles:. Some muscle groups on one side of the body are stronger than those on the other side.
Onset of FSH can occur in infants, but symptoms may appear at any time from childhood until someone is in their 50s. Typical facial features of FSH include:. In severe early-onset FSH, deafness is a common symptom. Changes also occur in the eyes, although this seldom affects vision. However, people with FSH should have their eyes checked regularly. Other issues faced by people with FSH include:. Due to the understated and variable nature of FSH symptoms, health professionals are sometimes challenged to identify the condition.
This is where genetic testing can quickly assist with a diagnosis. On average, FSH muscular dystrophy progresses slowly and the level of severity eventually seems to plateau level off. In very mild cases, it may not be possible to detect that the disease is progressing. Myotonic dystrophy is the most common adult form of muscular dystrophy. It is also known as Steinert's disease and dystrophia myotonica. Unlike the other muscular dystrophies, the muscle weakness is accompanied by myotonia delayed relaxation of muscles after contraction and by various other non-muscular symptoms.
The first muscles to be affected by weakness are those of the face, neck, hands, forearms, and feet. Myotonic dystrophy can affect the tissues and organs of many body systems.
The effects can include:. Fifty per cent of people with myotonic dystrophy show visible signs by about twenty years of age. But a significant number do not develop clear-cut symptoms until after age fifty. When myotonic dystrophy is suspected because it is present in other members of the family , careful examination may reveal typical features before obvious symptoms appear.
Myotonic dystrophy is inherited in an autosomal dominant manner. This means that the condition can be caused by inheriting just one copy of the altered gene. We inherit one copy of each gene from our mother and father. Therefore, when a person with myotonic dystrophy goes on to have children, there is a 50 per cent chance that each child will have myotonic dystrophy.
The course of myotonic dystrophy varies widely, even in the same family. There are people with the condition whose symptoms are so mild they hardly know the condition is present. Whatever muscle weakness they experience is something they assume to be normal and adapt to. In some cases, the only symptom may be a cataract. Nevertheless, these people do have myotonic dystrophy and can transmit a more severe version of the condition to their children.
In most cases, weakness and muscle wasting starts with certain muscles and slowly progresses to the point of some physical inability. As it progresses it moves beyond the muscles originally involved to those of the shoulders, hips, and thighs. This muscle weakness rarely becomes severe until fifteen to twenty years after the onset of symptoms.
The older a person is when muscle weakness is first noticed, the slower it progresses and the less serious the condition and effects. The congenital muscular dystrophies CMDs are a group of conditions that vary in severity and rates of progression.
Congenital means 'from birth'. In most cases of congenital muscular dystrophy, the initial symptoms are present at birth or in the first few months. Babies with CMD often have low muscle tone or floppiness and may have reduced movements. Other common signs are contractures tightness in the ankles, hips, knees and elbows. Some babies may also have trouble breathing and feeding. Some improvement often occurs in childhood and the disease shows little or no progression.
Because the specific gene involved in muscular dystrophy has been found, a replacement gene that could create the missing dystrophin protein is a sensible consideration. There are complicated problems with this approach, including the potential of the immune system to repel a new protein and the large size of the dystrophin gene needing to be replaced.
There are also difficulties in targeting viral vectors directly to the skeletal muscle. Another approach targets utrophin production.
Utrophin is a protein similar to dystrophin that is not affected by muscular dystrophy. If utrophin production could be upregulated, the disease might be halted or slowed. If the dystrophin gene is being read by protein synthesis machinery and it reaches a mutation, it stops and does not complete the protein. Drugs are being trialed that cause the protein-making equipment to skip the mutated content and still continue to create dystrophin.
Rather than target the genes behind muscular dystrophy, some researchers are attempting to slow the inevitable muscle wasting.
Muscles, in standard circumstances, can repair themselves. Research into controlling or increasing these repairs could show some benefits for people with muscular dystrophy. Researchers are looking at the possibility of inserting muscle stem cells capable of producing the lacking dystrophin protein.
Current projects are looking at the most useful type of cells to use and ways in which they could be delivered to skeletal muscle. During the early stages of muscular dystrophy, myoblasts also called satellite cells repair and replace faulty muscle fibers. As the myoblasts become exhausted, the muscles are slowly turned into connective tissue.
Some studies have attempted to insert modified myoblast cells into muscles to take over from the exhausted natural myoblasts. Spinal muscular atrophy SMA is a collection of inherited neuromuscular diseases. Human clinical trials are underway for some of these strategies. For an overview of DMD research strategies and the latest research news, see Research. On Sept. On Feb. Skip to main content. Search MDA.
Search Donate. What causes DMD? What is the life expectancy in DMD? What is the status of DMD research? Parsippany, NJ. This content does not have an English version. This content does not have an Arabic version. Overview Muscular dystrophy is a group of diseases that cause progressive weakness and loss of muscle mass.
Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Show references Ferri FF. Muscular dystrophy. In: Ferri's Clinical Advisor Elsevier; Accessed Dec. NINDS muscular dystrophy information page. National Institute of Neurological Disorders and Stroke.
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