Symptoms
Until recently, children with Duchenne muscular dystrophy (DMD) did not often live beyond their teens. However, improvements in cardiac and respiratory care mean that life expectancy is increasing, with many DMD patients reaching their 30s, and some living into their 40s and 50s.
Causes
- Upward slanting eyes
- Small, low set ears
- Small nose with a flat nasal bridge
- Flattened face
- Short neck
- A tongue that sticks out
- Small hands and feet
- Single palmar crease (line across the palm)
- Curved and small pinky fingers
- Hypotonia (low muscle tone)
Prevention
Symptoms of Emery-Dreifuss muscular dystrophy include:
- Weakness starts in the arms and later affects the legs Sometimes weakness occurs in the face
- Heart problems
- Limited movement at certain joints caused by tightening of the tissues around the joint (contracture)
Complications
Until now, experts believed more than 70,000 people had muscular dystrophy, but new research suggests this figure is actually over 110,000. It also found that people seem to be living longer with muscular dystrophy than previous studies have suggested.
What is the life expectancy of muscular dystrophy?
What is the life expectancy of someone with dystrophy?
What are the first signs of muscular dystrophy?
What is the prognosis of muscular dystrophy?
See more
What is the main cause of muscular dystrophy?
MD is caused by mutations (alterations) in the genes responsible for healthy muscle structure and function. The mutations mean that the cells that should maintain your muscles can no longer fulfil this role, leading to muscle weakness and progressive disability.
How do you get Duchenne muscular dystrophy?
Causes. DMD is inherited as an X-linked disease. X-linked genetic disorders are conditions caused by an abnormal gene on the X chromosome and manifest mostly in males. Females that have a defective gene present on one of their X chromosomes are carriers for that disorder.
Why do only males get Duchenne muscular dystrophy?
DMD generally affects boys because the dystrophin gene is on the X chromosome. Chromosomes are the parts of your cells that contain your genes. Boys only have one X chromosome. Girls have two X chromosomes, one from each parent.
Which parent carries the muscular dystrophy gene?
Inheritance in DMD DMD is inherited in an X-linked pattern because the gene that can carry a DMD-causing mutation is on the X chromosome. Every boy inherits an X chromosome from his mother and a Y chromosome from his father, which is what makes him male.
Who is most likely to get Duchenne muscular dystrophy?
Duchenne muscular dystrophy mostly affects boys and occurs in one in 3,500 to 5,000 newborns. There is no higher risk for any ethnic group. Children affected by DMD may have some degree of cognitive problems, yet some have average or even higher-than-average intelligence.
Why are babies born with muscular dystrophy?
What Causes Muscular Dystrophy? Muscular dystrophy is a genetic condition. Genetic conditions are passed from a parent (or parents) to their child. In muscular dystrophy, a gene change prevents the body from making the proteins needed to build and maintain healthy muscles.
Can Duchenne muscular dystrophy be prevented?
Because DMD is a genetic disorder, you can't do much to prevent it. But if DMD runs in your family, you may consider talking with a genetic counselor and getting testing before having children.
Can you prevent muscular dystrophy?
Unfortunately, there isn't anything you can do to prevent getting muscular dystrophy. If you have the disease, these steps can help you enjoy a better quality of life: Eat a healthy diet to prevent malnutrition.
Can Duchenne muscular dystrophy be detected before birth?
Chorionic villus sampling (CVS) and amniocentesis (AC) are commonly used invasive prenatal testing (IPTs) for the prenatal diagnosis of DMD.
Can females get Duchenne muscular dystrophy?
Duchenne muscular dystrophy usually affects males. However, females are also affected in rare instances. Approximately 8% of female Duchenne muscular dystrophy (DMD) carriers are manifesting carriers and have muscle weakness to some extent.
Can you test for muscular dystrophy during pregnancy?
Genetic testing can also be used for prenatal diagnosis. This is when a baby is diagnosed with MD before birth using tests carried out during pregnancy. You may be offered these tests if you're pregnant and there's a possibility that your unborn baby has MD.
What race is muscular dystrophy most common in?
It appears that DMD is significantly more common in white males than in males of other races.
Causes of Duchenne Muscular Dystrophy
Some boys who get Duchenne muscular dystrophy have no family history of muscle disorders. However, Duchenne usually is passed from the mother to child through an abnormal gene in the mother's DNA. The mother can carry the defective gene without knowing it or having any symptoms of a neuromuscular disease.
Clinical Trials
Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.
What is the most common form of muscular dystrophy?
Duchenne muscular dystrophy ( DMD) is a genetic condition characterized by progressive weakening of voluntary muscles. DMD worsens more rapidly than other types of muscular dystrophy. It’s also the most common form of muscular dystrophy. The Centers for Disease Control and Prevention. Trusted Source. estimated that one out of every 5,600 ...
What is the test for muscular dystrophy?
The blood test used to reach this diagnosis is called a creatine phosphokinase test. When muscles deteriorate, they release a large amount of creatine phosphokinase enzyme into the blood. If the test detects high levels of creatine phosphokinase, muscle biopsies or genetic tests will determine the type of muscular dystrophy.
How do you know if you have DMD?
The symptoms of DMD generally start to appear between ages 2 and 6. Many children with DMD develop normally during infancy and early childhood. DMD symptoms may include: 1 difficulty walking 2 a loss of ability to walk 3 enlarged calves 4 learning disabilities, which occurs in about one-third of affected individuals 5 a lack of motor skills development 6 fatigue 7 rapidly worsening weakness in the legs, pelvis, arms, and neck
How long can a person with DMD live?
However, with diligent care, some people with DMD survive into their 30s. In the later stages of the disease, most people with DMD will need full-time care to maintain quality of life. The condition is degenerative, which means that the need for medical care increases as the condition worsens.
What is a DMD?
DMD is a genetic disease. Those who inherit it have a defective gene related to a muscular protein called dystrophin. This protein keeps muscle cells intact. Its absence causes rapid muscular deterioration as a child with DMD grows.
What are the symptoms of DMD?
DMD symptoms may include: difficulty walking. a loss of ability to walk. enlarged calves. learning disabilities, which occurs in about one-third of affected individuals. a lack of motor skills development. fatigue. rapidly worsening weakness in the legs, pelvis, arms, and neck.
Can you cure DMD?
There’s no cure for DMD. Treatment can only make symptoms less severe and extend life expectancy. Children with DMD often lose the ability to walk and require a wheelchair by about age 12. Leg bracing may extend the amount of time a child can walk independently.
Why does Duchenne have a dysfunctional protein?
But no matter the type of mutation, in Duchenne, it results in a dysfunctional protein — usually because it causes a premature stop codon, cutting the molecule short. “The end result is always the same,” says Nelson. “No dystrophin.”.
What are the two types of mutations that cause Duchenne?
Deletions and duplications are two kinds of mutations that can cause Duchenne, with long stretches of DNA called exons — which contain tens of thousands to millions of nucleotides — either left out or repeated when a cell divides. About 60 to 70 percent of mutations that cause Duchenne are deletions, according to Nelson.
Why does dystrophin matter?
Why Dystrophin Matters. In normal muscle cells, dystrophin transfers the force of muscle contractions from the inside toward the outside of the cell. “Dystrophin is the shock absorber that helps mitigate any damage in the muscle when muscle cells contract,” explains Barry Byrne, MD, PhD, the director of the Powell Gene Therapy Center at ...
What is the role of dystrophin in muscle contractions?
Dystrophin acts as a shock absorber within the muscle cells, reducing any damage caused by muscle contractions. Shutterstock. Duchenne muscular dystrophy, a genetic disease characterized by progressive muscle weakness, is present at birth in people who have the condition. In people with Duchenne, the muscles lack a protein called dystrophin, ...
Which gene is responsible for producing dystrophin?
The DMD gene — the one responsible for producing dystrophin — happens to be one of the largest or longest genes in humans, and it’s particularly prone to mutations. About 1 in 10,000 cell divisions result in a mutation in this gene, according to Dr. Nelson.
What is the middle of dystrophin?
The middle of the dystrophin molecule consists of a long series of repeated units, known as spectrin units.
What is Duchenne muscular dystrophy?
Duchenne muscular dystrophy ( DMD) affects the muscles, leading to muscle wasting that gets worse over time. DMD occurs primarily in males, though in rare cases may affect females. The symptoms of DMD include progressive weakness and loss (atrophy) of both skeletal and heart muscle. Early signs may include delayed ability to sit, stand, ...
What causes muscle weakness in children?
Heart and breathing problems also begin in the teen years and lead to serious, life threatening complications. DMD is caused by genetic changes ( DNA variants) in the DMD gene.
Why do boys with DMD have breathing problems?
By the early teens, most boys with DMD are using a wheelchair. Breathing problems occur due to weakness of the diaphragm and the other muscles around the lungs. Scoliosis and tight joints ( contractures) may develop as muscle loss gets worse.
Is DMD inherited?
DMD is inherited in an X-linked recessive pattern and may occur in people who do not have a family history of DMD. Diagnosis of DMD is based on the symptoms, clinical exam, and the result of a biopsy to remove a small piece of muscle for examination under a microscope.
Is Duchenne muscular dystrophy a recessive disorder?
Duchenne muscular dystrophy (DMD) is inherited in an X-linked recessive pattern. [1] . X-linked means that the gene for the condition is located on the X- chromosome, one of the sex chromosomes. In males (who have only one X chromosome ), one altered copy of the gene is enough to cause the condition.
What is the name of the mutation that causes muscular dystrophy?
About Duchenne Muscular Dystrophy. Duchenne muscular dystrophy (DMD) is a rapidly progressive form of muscular dystrophy caused by a mutation in the DMD gene.
How old do you have to be to walk with Duchenne muscular dystrophy?
The mean age for walking in boys with Duchenne muscular dystrophy is 18 months. There is progressive muscle weakness of the legs and pelvic muscles, which is associated with a loss of muscle mass (wasting). This muscle weakness causes a waddling gait and difficulty climbing stairs.
What is a woman who has a genetic change in one of her two copies?
A woman who has a genetic change in one of her two copies is said to be "a carrier" of Duchenne muscular dystrophy. Carriers do not have Duchenne muscular dystrophy and most are unaware that they even carry this change in their genetic material unless they have a family history.
What is the cause of DMD?
It is caused by an alteration (mutation) in a gene, called the DMD gene that can be inherited in families in an X-linked recessive fashion, but it often occurs in people from families without a known family history of the condition.
Do boys with Duchenne muscular dystrophy have dystrophin?
Boys with Duchenne muscular dystrophy do not make the dystrophin protein in their muscles. Duchenne muscular dystrophy affects approximately 1 in 3500 male births worldwide. Because this is an inherited disorder, risks include a family history of Duchenne muscular dystrophy.
Does prednisone help with DMD?
The medication prednisone - a steroid - is given to improve the strength and function of individuals with DMD. Prednisone has been shown to prolong the ability to walk by 2 to 5 years. However, the possible side effects of prednisone include weight gain, high blood pressure, behavior changes, and delayed growth.
Where does muscle weakness occur?
Muscle weakness also occurs in the arms, neck, and other areas, but not as severely or as early as in the lower half of the body. Calf muscles initially enlarge and the enlarged muscle tissue is eventually replaced with fat and connective tissue (pseudohypertrophy).
How many babies are affected by Duchenne muscular dystrophy?
Duchenne muscular dystrophy mostly affects boys and occurs in one in 3,500 to 5,000 newborns. There is no higher risk for any ethnic group. Children affected by DMD may have some degree of cognitive problems, yet some have average or even higher-than-average intelligence.
What is the most severe muscular dystrophy?
Duchenne muscular dystrophy, or DMD, is associated with the most severe clinical symptoms of all the muscular dystrophies. It is caused by a genetic mutation on one of the mother’s X chromosomes, and researchers have identified some of the affected genes.
What causes muscle weakness?
Muscle weakness may affect the skeletal muscle or the heart muscle. It is caused by the inability of muscles to respond to nerve impulses from the brain.
What is the cause of DMD?
DMD is a genetic disease caused by a gene on the X chromosome that mothers can pass on to their sons. The gene affects a protein called dystrophin that muscles require to function normally.
What is the best treatment for DMD?
The first line of treatment is corticosteroids, which have been shown in clinical trials to decrease the rate of declining strength in people with DMD.
How old is too old to have DMD?
DMD most commonly appears in children between 3 and 6 years old. Children may have difficulty walking or getting up from a seated position or from lying down. Parents or caretakers may notice weakness of the shoulder and pelvis, abnormal clumsiness and frequent falling. Other symptoms and signs include:
Function
Causes
Symptoms
Mechanism
Genetics
- Genes contain codes, or recipes, for proteins, which are important biological components in all forms of life. In 1987, the protein associated with this gene was identified and named dystrophin. The dystrophin protein transfers the force of muscle contraction from the inside of the muscle c…
Risks
- DMD occurs because the mutated gene fails to produce virtually any functional dystrophin. (Individuals with Becker MD genetic mutations make dystrophin that is partially functional, which protects their muscles from degenerating as badly or as quickly as in DMD.) Although DMD often runs in a family, it's possible for a family with no history of DMD to suddenly have a son with the …
Diagnosis
- Lack of dystrophin causes muscle damage and progressive weakness, beginning in early childhood. Usually, however, girls dont experience the full effects of DMD the way boys do, although they still have symptoms of muscle weakness. A minority of females with the mutation, called manifesting carriers, have some signs and symptoms of DMD. For these women, the dyst…