Duchenne and becker muscular dystrophy

Sometimes, Duchenne muscular dystrophy (DMD) and Becker muscular dystrophies (BMD) can cause neurological problems. This includes intellectual disability, speech and language delays, and learning difficulties. Intellectual disability does not get worse as a child ages. Neurological problems are more likely in children with DMD than in BMD. Some estimates state that as many as one-third of children with DMD have neurological problems. Duchenne and Becker muscular dystrophies are caused by alterations in the DMD gene. This gene produces a protein called dystrophin. This protein is found primarily in skeletal and heart muscle tissue, but is also found in the brain in small amounts. Doctors don’t completely understand why some children with these disorders have neurological problems.

Some toddlers or children with Duchenne muscular dystrophy and some children with Becker muscular dystrophy may have enlarged calves. This is called pseudohypertrophy. Pseudo meaning ‘false’ and hypertrophy meaning ‘enlargement’. The muscle tissue is abnormal in the calves of people with these disorders and may contain scar tissue. This gives the false impression that the muscles are large and strong. Pseudohypertrophy occurs in several different muscle disorders and should prompt doctors to give children a more thorough examination.

In a family with Duchenne or Becker muscular dystrophy, tests can be done to see whether other family members are carriers for the disorder. However, the specific gene changes in that family needs to be known. If known, testing can be done on all siblings and other at-risk relatives such as first-degree female relatives of a known or possible carrier. Testing for carrier status for Duchenne or Becker muscular dystrophy is done through molecular genetic testing. This type of testing looks for changes to genes. A newborn boy in a family with a history of Duchenne or Becker muscular dystrophy should be tested through molecular genetic testing. Confirming a diagnosis allows therapy to be started as soon as possible. Women or girls can be tested to see if they carry the altered gene. A genetic counselor or a physician with experience in diagnosing and treating these disorders can provide advice about how a confirmed diagnosis can affect other family members.

To find a genetic professional near you who can discuss genetic testing, visit the following two sites: A listing of medical geneticists can be found at the American College of Medical Geneticists website (www.acmg.net) and genetic counselors can be found on the National Society of Genetic Counselors website: www.nsgc.org.

Support groups can put you in contact with other people or families that have Duchenne or Becker muscular dystrophy. Support groups for these disorders include Support groups for Duchenne and Becker muscular dystrophies include the Cure Duchenne, Muscular Dystrophy Association, Muscular Dystrophy Canada, Parent Project Muscular Dystrophy (ThinkGenetic Partner), and the European Alliance of Neuromuscular Disorders Associations.

There are also online communities for rare disorders such as RareConnect, RareShare, or Inspire, which allow individuals and parents to share experiences and advice about dealing with rare disorders.

Taking care of someone with a long-term or chronic condition can be tiring and challenging and this is no different for parents or other caregivers of people with Duchenne or Becker muscular dystrophy. If you are a caregiver in need of support, try to take time for yourself, set aside time for personal counseling, or look for other resources at the [link url=" http://caregiveraction.org/” target=”_blank”>Caregiver Action Network. This organization works to improve the quality of life for people who care for loved ones with chronic conditions, disabilities, disease, or the frailties of old age. Support groups can also help provide support and advice for caregivers. Support groups for Duchenne or Becker muscular dystrophy include: the Cure Duchenne, Muscular Dystrophy Association, Muscular Dystrophy Canada, Parent Project Muscular Dystrophy (ThinkGenetic Partner), and the European Alliance of Neuromuscular Disorders Associations.

Rare diseases that affect multiple organ systems can benefit from a multidisciplinary approach. This approach involves healthcare professionals with specialized skills and expertise. They work together to make treatment recommendations and to provide quality care of individuals and families. Depending upon the specific symptoms in an individual multidisciplinary team may require a specialist for neurological disorders in children (pediatric neurologist) who will monitor brain function and health; a heart doctor (cardiologist) who can monitor heart function and health; a lung doctor (pulmonologist) who can monitor lung function and health; a psychiatrist to monitor and treat emotional or behavior problems; a specialist who can monitor the function and health of the bones, muscles, ligaments, tendons, and nerves (orthopedist); a genetic counselor who can help people understand the disease and the implications for the person and other family members, a metabolic disease specialist, a specialist in digestive disorders (gastroenterologist), physiotherapists, physical therapists, speech therapists, occupational therapists, social workers, and dieticians.

Duchenne muscular dystrophy (DMD) is progressive neuromuscular disorder. Without treatment, most boys pass away before reaching adulthood. Improvements in the general care of patients, a better understanding of the disorder, and newer or improved treatments has improved life expectancy. Many patients live into their 20s or 30s, and some men live into their 40s and 50s. Men with DMD can go to college, have careers, get married, and start families. Although the symptoms of DMD are very similar among people with the disorder, everyone is unique and broad generalizations about quality of life or life span is difficult. Individuals and families with someone with DMD should talk to their physician and medical team about their unique situation and prognosis.

Becker muscular dystrophy (BMD) is a highly variable disorder. This means that the symptoms and the severity of the disorder can be very different in different people. Some people may have mild symptoms, while others have very severe symptoms. When the symptoms first begin and how fast they get worse can also be very different. Because of this variability, making broad generalizations about the prognosis or life expectancy of people with BMD is difficult. Individuals and families with someone with BMD should talk to their physician and medical team about their unique situation and prognosis.

The optimal time to start treatment with corticosteroids has not been established for children with Duchenne or Becker muscular dystrophy. It is considered the treatment of choice for children between the ages of 5-15. Some doctors recommend starting as soon as a diagnosis is confirmed, often between 2-5 years of age for Duchenne muscular dystrophy. However, there are no large-scale controlled clinical trials to evaluate early corticosteroid treatment in Duchenne muscular dystrophy. Corticosteroid therapy is not recommended in children under age two years of age.

In September of 2016, the U.S. Food and Drug Administration (FDA) approved an weekly infused medication called EXONDYS 51™ (eteplirsen) made by Sarepta Therapeutics for some Duchenne and Becker muscular dystrophy (DMD/BMD) patients with a specific category of "misspelling" or gene mutation. This treatment will not work for every patient with DMD/BMD, just those with nonsense mutations that will allow skipping a part of the gene called exon 51.

In order to learn if this medication is an option, you can speak with your main DMD/BMD doctor. If you do not have a DMD/BMD expert team who works with you, support groups such as Parent Project Muscular Dystrophy have information on their websites to help you find expert doctors at Certified Duchenne Care Programs with experience working with patients affected by DMD/BMD.

Duchenne muscular dystrophy (DMD) is a genetic muscle disorder that causes weakness and wasting (atrophy) of the muscles. The first signs of DMD are often that the baby is late to sit, stand, and walk. When many children with DMD do walk it may be mainly on their toes (toe-walking) or with an odd waddle. Toddlers and children also may have large calves due to muscle damage (pseudohypertrophy). Muscle weakness usually starts in the pelvic and hip area and then moves to other muscles. Next it can affect the shoulder muscles, trunk, and arms. The disease gets worse over time (is progressive) and most people require a wheelchair by their teenage years to move around. Serious life-threatening complications may ultimately develop including disease of the heart muscle (cardiomyopathy) and breathing (respiratory) difficulties. Many of those affected do not survive past their mid-20s. Sometimes, there is mild to moderate intellectual disability and learning difficulties as well. DMD is caused by a genetic change in the DMD gene, which prevents the gene from producing dystrophin. Dystrophin is a protein that helps keep muscle cells intact and working. The disease primarily affects boys, but in rare cases it can affect girls.

Becker muscular dystrophy (BMD) is a genetic muscle disorder that causes weakness and wasting (atrophy) of the muscles. The first signs of usually appear between 5 and 15 years of age. Muscle cramping or reduced stamina after exercise are often the first signs. Affected muscle slowly deteriorates, particularly in the hips, pelvis, thighs and shoulders. Eventually, affected people require a wheelchair to get around. The heart can also be affected. People with BMD can develop dilated cardiomyopathy in their 40s. Dilated cardiomyopathy is a condition in which the heart muscle becomes enlarged and the heart cannot pump blood effectively. It can lead to heart failure. Some people do not have any skeletal muscle problems, but develop cardiomyopathy as adults. BMD is a milder disorder compared to the related disorder, Duchenne muscular dystrophy (DMD). BMD will get worse as affected people get older, but at a much slower rate than DMD does. These disorders are caused by a genetic change in the same gene, the DMD gene. In BMD, this genetic change causes the DMD gene to produce a partially functional protein. This protein, called dystrophin, is a protein that helps keep muscle cells intact and working. The disease primarily affects boys, but in rare cases it can affect girls.

Some children with Duchenne or Becker muscular dystrophy will have problems getting up from the floor. This is because the muscles of the knees and hips that they need to use to get up are weakened. To compensate they will often use their arms when attempting to get up, and will move (or ‘walk’) their hands up their thighs in order to stand up fully. This is called Gower’s maneuver or Gower’s sign. It is a distinctive maneuver in people who lack muscle strength in the upper legs. A child who shows this maneuver often has a muscle disorder like Duchenne or Becker muscular dystrophy.

Duchenne and Becker muscular dystrophies are caused by unexpected changes, called mutations, in a gene called DMD. People have about 20,000-25,000 genes in their bodies. Genes contain our body’s genetic information, called DNA. Genes are inherited from our parents and passed on to our children. Genes are like our body’s instruction manual – they control the growth, development and normal function of the body. When a mutation happens in a gene, the gene may not work properly. It is like a section of the body’s instruction manual is not correct, and that can cause problems with the normal development and functioning of the body. Specifically, genes produce proteins that the body needs to grow and work properly. When there is a change in a gene, the protein that the gene produces may be absent or not work properly. This interferes with proper growth and development.

A child with Duchenne or Becker muscular dystrophy demands a lot of time and focus from parents. Although studies have shown that siblings of children with chronic illness tend to develop strong levels of compassion and empathy, these studies have also shown that siblings can develop feelings of jealousy and anger and high levels of anxiety. It is possible for healthy siblings to feel as if they have been pushed aside when parents focus more of their efforts on their child with a chronic illness. Parents should encourage healthy siblings to discuss their concerns and feelings about living with a sibling with a chronic illness. It is important for parents to acknowledge and address these concerns with their healthy children. Healthy siblings can feel more included in the family structure when they help with the care of their sick sibling. Parents are encouraged to make time for activities specifically for healthy siblings. Some siblings may benefit from support outside of the immediate family, such as meeting with a therapist. The Sibling Support Project is a nonprofit organization that serves the concerns and needs of siblings of people with special health, developmental, and mental health needs. There are also regional support groups for siblings of children with serious health conditions. Your child’s pediatrician or your local hospital may be able to tell you if this type of support group is available in your area.

All medications have the potential for side effects. Corticosteroids like prednisone are a standard treatment for people with Duchenne or Becker muscular dystrophy. They improve the strength and function of muscle in people with these disorders. Prednisone is commonly used in the United States. Side effects of prednisone include weight gain, acne, high blood pressure, gastrointestinal symptoms, behavior changes, delayed growth, and an increased risk of osteoporosis. Individuals and parents should talk to their doctors and medical team about potential side effects and how to manage these side effects before beginning any treatment.

The main symptom of Duchenne muscular dystrophy is progressive weakness and wasting of certain muscles. The muscles of the upper legs, pelvis, and shoulder are often affected. The first signs may be in young children who fail to reach developmental milestones on time. There may be delays in their ability to sit up, stand without assistance, or walk. Because of the progressive muscle weakness, children may walk on their toes or have an unusual manner to how they walk. They may seem awkward and clumsy. They may have problems climbing stairs. Many children never are able to run or jump. Children with DMD with eventually need braces or other assistive devices to help them walk. Ultimately, most people with DMD require a wheelchair.

Some children may develop a sideways curving of the spine called scoliosis. They can also develop contractures, which is when a joint becomes permanently fixed in a bent or straightened position, completely or partially restricting the movement of the affected joint. Some young children may have very large calves, a condition called pseudohypertrophy. Some children have mild or moderate intellectual disability, which can cause learning difficulties. Some children may have speech and language delays.

DMD can also affect the heart. In the late teen-aged years, many people develop weakness and deterioration of the heart muscle. This can lead to irregular heartbeats, fatigue, exercise intolerance, and shortness of breath. It can hinder the heart’s ability to pump blood and eventually result in heart failure.

Weakness and wasting of muscles of the rib cage can also happen. This cause people to have repeated respiratory infections, difficulty breath and a chronic cough. Ultimately, respiratory failure can occur.

Becker muscular dystrophy (BMD)usually begins in the teens or early twenties, but can begin as late as the sixties. The symptoms that develop can be very different among people with this disorder. Generally, the symptoms are milder than the related disorder, Duchenne muscular dystrophy. BMD is characterized by muscle weakness and deterioration that progresses slowly. The hip, pelvic area, thighs and shoulders are often affected. People with this disorder may experience muscle cramps and as the disorder gets worse may have problems running, climbing stairs or rising from a chair. Many individuals eventually need a wheelchair to get around, although at what age this happens can vary. Some men with a very mild form of the disorder have not developed symptoms until their 30s and remain able to walk into their 60s. Other people may need a wheelchair by their 20s.

In some people with BMD, the heart muscle may deteriorate (cardiomyopathy), often more seriously than the skeletal muscles of the body. This may be first seen as shortness of breath or exercise intolerance. but can become life-threatening potentially causing heart failure. Some people with BMD will develop cardiomyopathy as adults, but will not develop problems with skeletal muscle.

Although not common, some people with BMD may have mild cognitive and behavioral issues that can lead to learning difficulties.

After a diagnosis of Duchenne or Becker muscular dystrophy (DMD/BMD) is confirmed, families should talk to doctors (medical geneticists and/or neurologists) and genetic counselors with experience in treating DMD/BMD. Support groups such as Parent Project Muscular Dystrophy have information on their websites to help you find expert doctors at Certified Duchenne Care Programs with experience working with patients affected by DMD/BMD. CureDuchenne and the Muscular Dystrophy Association can also provide referrals to physicians or medical centers with experience in evaluating and treating these disorders. People diagnosed with Duchenne or Becker muscular dystrophy will go through a series of tests to see what parts of the body are affected by DMD/BMD and how severely. Other initial steps will depend on how the disorder is affecting a person. The doctors will then put together a treatment plan for that individual. One option to learn more about possible treatment plans is to visit the "Standards of Care" webpage at CureDuchenne’s website.

At the same time, it can be very useful to reach out to DMD/BMD support and advocacy groups that provide more information about living with DMD/BMD as well as connecting you with other families with with DMD/BMD. Support groups for DMD/BMD include:

Toddlers and children with Duchenne muscular dystrophy may not reach milestones like sitting up or standing on their own when they would normally be expected to. Parents may notice their children have difficulty getting up from the floor, climbing stairs, or walking or running. When walking, they may walk on their toes or walk in an unusual manner. Parents may think their children are clumsy because they may fall often.

Although newborn screening for Duchenne muscular dystrophy was performed in Wales and has been done before as a "pilot" projects or studies in the United States, it is not routinely tested for in any state in the United States in 2016. Nationwide Children’s Hospital in Ohio has developed a good test for newborn screening and this is a first step towards being added to some states’ testing programs; however, DMD is not currently on the United States recommended uniform screening panel (RUSP) that many states use to decide if they should test for a condition.

Several different tests may be done when a doctor suspects Duchenne or Becker muscular dystrophy as a diagnosis. One of the first tests is a creatine phosphokinase (CPK) blood test. A positive test means that the CPK level is high, which can mean a problem with the muscles. CPK is an enzyme. When muscle tissue is damaged, CPK leaks out into the bloodstream. CPK testing cannot be used to make a final diagnosis; it tells the doctors that the problem is with the muscles themselves and not with the nerves that supply the muscles.

A diagnosis can be confirmed by genetic testing, which uses tests that can detect changes in the DMD gene. This can include deletion/duplication analysis, where missing or extra regions of DNA are looked for within a specific gene, or sequence analysis, where a part or sequence of DNA within a gene is examined. Molecular genetic testing must be done at specialized laboratories. These tests are usually done on a blood sample.

If genetic testing cannot identify an alteration in the DMD gene, then doctors may need to perform a muscle biopsy. A muscle biopsy collects a small piece of muscle that is then looked at for changes in the amount of dystrophin and the appearance and condition of muscle fibers. This type of testing can usually tell whether a person has Duchenne or Becker muscular dystrophy or another muscle issue.

To find a genetic professional near you who can discuss genetic testing, visit the following two sites: A listing of medical geneticists can be found at the American College of Medical Geneticists website (www.acmg.net) and genetic counselors can be found on the National Society of Genetic Counselors website: www.nsgc.org.

There are several organizations that can help individuals and families with Duchenne and Becker muscular dystrophies who are dealing with neurological problems. If untreated, a diverse and wide variety of neurological complications may develop in people. Many different organizations provide support and information for these issues. The Arc provides support and services to people with intellectual and developmental disabilities. The National Mental Health Institute and the National Alliance on Mental Illness also provide a wide range of services, information, support, guidance and referrals for people of all ages.

Muscular dystrophy support groups can also provide information. These support groups include, the Muscular Dystrophy Association; Muscular Dystrophy Canada; Muscular Dystrophy UK; and Parent Project Muscular Dystrophy (ThinkGenetic Partner).

As of June 2016, there are about 179 studies for Duchenne and Becker muscular dystrophy listed on clinicaltrials.gov, a government website that provides regularly updated information about federally and privately supported clinical trials. This is not an exhaustive list of current research. Current studies are looking at how the heart is involved in these disorders, strength training, natural history studies, and several treatments including stem cell therapy, gene therapy, and numerous different medications.

There is no cure for Duchenne muscular dystrophy (DMD). There are, however, several treatments used to help reduce the health problems seen in DMD such as physical therapy, exercise, and steroids. Physical therapy, braces, and active/passive exercise is done to build muscle strength and prevent a shortening, hardening, and stiffness of joints (contractures). Corticosteroids like prednisone and deflazacort are used to slow the progression of muscle weakness in people with DMD. There are several treatments being tried in research studies that could work to address the underlying problem in DMD. One option to learn more about possible treatment plans is to visit the "Standards of Care" webpage at CureDuchenne’s website.

In September of 2016, the U.S. Food and Drug Administration (FDA) approved an weekly infused medication called EXONDYS 51™ (eteplirsen) made by Sarepta Therapeutics for about 13% of patients with Duchenne and Becker muscular dystrophy (DMD/BMD) who have a specific category of "misspelling" or gene mutation. This treatment will not work for every patient with DMD/BMD, just those with nonsense mutations that will allow skipping a part of the gene called exon 51. In order to learn if this medication is an option, you can speak with your main DMD/BMD doctor. If you do not have a DMD/BMD expert team who works with you, support groups such as Parent Project Muscular Dystrophy have information on their websites to help you find expert doctors at Certified Duchenne Care Programs with experience working with patients affected by DMD/BMD.

When a woman is pregnant, it is possible to test the baby for certain conditions before the baby is born. This is called prenatal diagnosis. Some parents who have a family member with Duchenne or Becker muscular dystrophies may choose to test for these disorders before birth. These disorders are caused by an unexpected change, called a mutation, in a gene called DMD. People have about 20,000-25,000 genes in their bodies. Our genes contain our body’s genetic information, called DNA. Genes are inherited from our parents and passed on to our children. Genes are like our body’s instruction manual – they control the growth, development and normal function of the body. When there is an unexpected change in a gene, the gene may not work properly. It is like a section of the body’s instruction manual is not correct, and it can cause problems with the normal development and functioning of the body. When there is a mutation in the DMD gene, it can cause Duchenne or Becker muscular dystrophy.

If the specific DMD gene change that is causing Duchenne or Becker muscular dystrophy in the family is known, then prenatal testing can be performed. During the pregnancy, a test called chorionic villus sampling (CVS) can be performed to remove a sample of tissue from the placenta. Another test, called amniocentesis, involves taking a sample of the amniotic fluid that surrounds and protects a developing fetus. Only one of these tests needs to be performed. Genetic testing can then be performed on the cells from the placenta or the amniotic fluid to look for the DMD gene change.

Sometimes, a muscle biopsy, in which a small sample of muscle tissue is taken from the fetus, has been used to conduct genetic testing in families with Duchenne muscular dystrophy where the causative mutation in the DMD gene is not known.

Families considering prenatal testing should set up an appointment with a genetic counselor. A genetic counselor can explain the testing options and discuss reasons a family may or may not want to do prenatal diagnosis for one of these disorders. A genetic counselor can also help to explain the test results. A genetic counselor can be found using the National Society of Genetic Counselor’s “Find a Genetic Counselor” tool.

Some children with Duchenne muscular dystrophy may need palliative care. Palliative care ensures that a dying child is as pain free as possible and that all of their physical, social, emotional, and spiritual needs are met. Palliative care requires a close cooperation among family members, immediate relatives, and physicians, and other medical personnel. A primary care physician or local hospital may be able to offer advice and local resources for palliative care.

The International Children’s Palliative Care Network has specific information and support for families considering palliative care for their children. Additionally, the Global Genes Organization has information on rare genetic conditions and palliative care. This information can be found at: Pediatric Palliative Care.

Duchenne muscular dystrophy is caused by changes (mutations) in the DMD gene located on the short arm (p) of the X chromosome (Xp21.2). In most cases this change is inherited, or passed down in families. However, sometimes it happens for the first time (de novo) in the person with Duchenne muscular dystrophy. Whether it is new or passed down from a parent, the change in the DMD gene causes this gene to not work the way it should. The DMD gene has the instructions for the dystrophin protein, which is important to keep muscles together, strong, and working. Women have two X chromosomes (XX) and men have one X and one Y chromosome (XY). Women are usually unaffected carriers of Duchenne muscular dystrophy and are rarely affected because they have a backup working copy of the DMD gene on one of their X chromosomes. Men who inherit a non-working copy of the DMD gene on their X chromosome are affected with Duchenne muscular dystrophy because they only have one copy of the X chromosome and has no working DMD gene.

Eating right and getting proper nutrition is important for children with Duchenne or Becker muscular dystrophy. Following a healthy diet and getting proper nutrition is important for everyone, but people with Duchenne or Becker muscular dystrophy have weakened muscles and need to avoid putting too much stress on the muscle by putting on too much weight. Some doctors recommend a diet rich in vitamin D and calcium to strengthen bones and reduce the risk of fractures. Individuals with DMD or BMD or parents of affected children should talk to their medical team about eating right and proper nutrition.

Deflazacort is not available in the United States. Deflazacort is a type of corticosteroid. Corticosteroids are used to treat Duchenne and Becker muscular dystrophies because they can slow the progression of muscle wasting. Deflazacort is used in Europe to treat people with Duchenne or Becker muscular dystrophy. Some doctors believe that the side effects are not as bad as those with prednisone.

Duchenne muscular dystrophy is an X-linked genetic disorder, meaning that the altered DMD gene is passed from parent to child on the X chromosome. If a woman is a carrier for Duchenne muscular dystrophy, it means that she carries one altered DMD gene that does not work properly, and one unaltered DMD gene that does work properly. Women who are carriers usually do not have symptoms of these disorders because the unaltered copy of the gene can usually compensate for the altered copy. When a woman who is a carrier has a child, there is a 50% chance for her to pass on the altered copy and a 50% chance for her to pass on the unaltered copy. Her sons who inherit the altered copy will have Duchenne muscular dystrophy; her daughters who inherit the altered copy will be carriers like her. Children who inherit the unaltered copy will not have the disorder and cannot pass the genetic change onto their children.

Men only one X chromosome. So if a man has Duchenne muscular dystrophy then his X chromosome contains an altered copy of the DMD gene. He will pass this X chromosome on to all of his daughters, who will be carriers. Men pass their Y chromosome onto their sons, so men with Duchenne muscular dystrophy cannot pass the disorder onto their sons.

Some boys have Duchenne muscular dystrophy because of a change in the DMD gene that happened randomly at their conception and was not inherited from their mother. This is called a ‘de novo’ change. It happens spontaneously. The chance of another child in these families having Duchenne muscular dystrophy is very low. If the affected boy eventually has a child, his daughters would be carriers for Duchenne muscular dystrophy and his sons would not inherit the disorder (as described above).

A genetic counselor can help explain X-linked inheritance and how Duchenne muscular dystrophy is passed from generation to generation in families. A genetic counselor can be found using the National Society of Genetic Counselor’s “Find a Genetic Counselor” tool.

Becker muscular dystrophy is an X-linked genetic disorder, meaning that the altered DMD gene is passed from parent to child on the X chromosome. If a woman is a carrier for Becker muscular dystrophy, it means that she carries one altered DMD gene that does not work properly, and one unaltered DMD gene that does work properly. Women who are carriers usually do not have symptoms of these disorders because the unaltered copy of the gene can usually compensate for the altered copy. When a woman who is a carrier has a child, there is a 50% chance for her to pass on the altered copy and a 50% chance for her to pass on the unaltered copy. Her sons who inherit the altered copy will have Becker muscular dystrophy; her daughters who inherit the altered copy will be carriers like her. Children who inherit the unaltered copy will not have the disorder and cannot pass the genetic change onto their children.

Men only one X chromosome. So if a man has Becker muscular dystrophy then his X chromosome contains an altered copy of the DMD gene. He will pass this X chromosome on to all of his daughters, who will be carriers. Men pass their Y chromosome onto their sons, so men with Becker muscular dystrophy cannot pass the disorder onto their sons.

Some boys have Becker muscular dystrophy because of a change in the DMD gene that happened randomly at their conception and was not inherited from their mother. This is called a ‘de novo’ change. It happens spontaneously. The chance of another child in these families having Becker muscular dystrophy is very low. If the affected boy eventually has a child, his daughters would be carriers for Becker muscular dystrophy and his sons would not inherit the disorder (as described above).

A genetic counselor can help explain X-linked inheritance and how Becker muscular dystrophy is passed from generation to generation in families. A genetic counselor can be found using the National Society of Genetic Counselor’s “Find a Genetic Counselor” tool.

People with Duchenne and Becker muscular dystrophy will need to get their hearts checked on a regular basis. In 2005, the American Academy of Pediatrics published recommendations for monitoring the heart in people with Duchenne and Becker muscular dystrophies, including carriers for these disorders.

When treatment is required, doctors may recommend certain medications called angiotensin receptor blockers (ACE inhibitors) or beta blockers. These medications can be used by themselves or at the same time. ACE inhibitors cause blood vessels to open up, making it easier for the heart to pump blood throughout the body. Beta blockers slow down the heartbeat. If heart disease has progressed to heart failure, then diuretics or digoxin may be used. Diuretics remove excess water and salt from the body and makes it easier for the heart to pump blood. Digoxin slows and steadies heart muscle contractions, which helps to produce a more regular heartbeat.

Proper molecular genetic diagnosis is important for families with a child who has Duchenne or Becker muscular dystrophy. These disorders are caused by an alteration (mutation) in a gene called DMD. Molecular genetic diagnosis means that the doctors run tests in order to figure out the specific alteration in the DMD gene in that family. Knowing the specific alteration allows doctors to test other family members to see if they are carriers for the disease and is essential so people planning to have children can know what the risk of these disorders are in that family. There are also newer treatments being studied in clinical trials that will only be effective in people who have certain alterations in the DMD gene. Doctors need to know the specific alterations in individuals to know whether one of these treatments may be an option for them.

Duchenne and Becker muscular dystrophies are caused by changes in the DMD gene. This gene produces a protein called dystrophin. Dystrophin is found primarily in skeletal and cardiac muscle tissue. Dystrophin is essential for the proper health and development of these muscles. One of dystrophin’s functions is to serve as a ‘shock absorber’ during muscle contractions to protect and cushion muscle fibers. When there is a change in the DMD gene, the gene may have problems producing dystrophin. In Duchenne muscular dystrophy (DMD), there is very little or no dystrophin produced. In Becker muscular dystrophy (BMD), there is some dystrophin produced, but it does not function as well as it should. Because of the lack of functional dystrophin, muscle tissue in people with these disorders becomes damaged. The damage becomes worse over time. The muscles will weaken and deteriorate and the heart will be damaged, which can eventually cause heart failure. Because there is no or very little dystrophin in people with DMD, the disorder is more severe than BMD. DMD tends to occur earlier in life and progress much faster.

If a doctor suspects that a person has a muscle problem like Duchenne or Becker muscular dystrophy (DMD or BMD), it is likely they will order a creatine phosphokinase (CPK) blood test as a first step in the diagnostic process. A positive test means that the CPK level is high, which can mean a problem with the muscles. CPK testing cannot be used to make a final diagnosis, and is not genetic testing. If a CPK is high, there two types of tests that can be used to make a diagnosis of a muscular dystrophy like DMD or BMD: genetic testing and muscle biopsy. A muscle biopsy collects a small piece of muscle that is then looked at for changes in the amount and look of muscle fibers. This type of testing can usually tell whether a person has DMD, BMD, or another muscle issue. DNA-based genetic testing is used to find mutations (changes) in the gene that causes DMD and BMD. There are different genetic testing methods that find different types of mutations. You may need to have more than one genetic test to find a change. If the lab finds a mutation, most people will not need to have a muscle biopsy. Genetic testing is ordered through genetic counselors, doctors, and other healthcare providers. There are multiple labs that do testing and usually the one used depends on your insurance. If you do not have insurance, one option for testing is the Decode Duchenne project which provides free genetic testing and counseling to people with Duchenne or Becker muscular dystrophy who have been unable to access genetic testing in the past due to financial barriers. The application can be found online and needs to be completed by a doctor. (https://www.duchenneconnect.org/component/content/article.html?id=780)

If a doctor suspects that a person has a muscle problem like Duchenne or Becker muscular dystrophy (DMD or BMD), it is likely they will order a creatine phosphokinase (CPK) blood test as a first step in the diagnostic process. A positive test means that the CPK level is high, which can mean a problem with the muscles. CPK testing cannot be used to make a final diagnosis, and is not genetic testing. If a CPK is high, there two types of tests that can be used to make a diagnosis of a muscular dystrophy like DMD or BMD: genetic testing and muscle biopsy. A muscle biopsy collects a small piece of muscle that is then looked at for changes in the amount and look of muscle fibers. This type of testing can usually tell whether a person has DMD, BMD, or another muscle issue. DNA-based genetic testing is used to find mutations (changes) in the gene that causes DMD and BMD. There are different genetic testing methods that find different types of mutations. You may need to have more than one genetic test to find a change. If the lab finds a mutation, most people will not need to have a muscle biopsy. Genetic testing is ordered through genetic counselors, doctors, and other healthcare providers.

To find a genetic professional near you who can discuss genetic testing, visit the following two sites: A listing of medical geneticists can be found at the American College of Medical Geneticists website (www.acmg.net) and genetic counselors can be found on the National Society of Genetic Counselors website: www.nsgc.org.

There are multiple labs that do testing and usually the one used depends on your insurance. If you do not have insurance, one option for testing is the Decode Duchenne project which provides free genetic testing and counseling to people with Duchenne or Becker muscular dystrophy who have been unable to access genetic testing in the past due to financial barriers. The application can be found online and needs to be completed by a doctor. DuchenneConnect Testing Options

To learn about ongoing clinical research into Duchenne and Becker muscular dystrophies ask a physician who specializes in the disorder. Genetic counselors and medical geneticists are also excellence sources of information about ongoing clinical trials and can offer advice about the pros and cons about participating in such a trial.

Ongoing studies for Duchenne and Becker muscular dystrophies can also be found on clinicaltrials.gov, a service of the U.S. National Institutes of Health. In Europe, the EU Clinical Trial Register performs a similar service.

Support groups also have information about ongoing clinical trials as well as information and advice about participating in clinical trials. Support groups for Duchenne and Becker muscular dystrophies include the Cure Duchenne, Muscular Dystrophy Association, Muscular Dystrophy Canada, Parent Project Muscular Dystrophy (ThinkGenetic Partner), and the European Alliance of Neuromuscular Disorders Associations.

One of the best ways to find a treatment center or physician with experience in treating Duchenne or Becker muscular dystrophy is to contact a support group. The Muscular Dystrophy Association offers MD Care Centers around the United States. The Parent Project Muscular Dystrophy certifies medical centers around the country through its Certified Duchenne Care Center Program. Genetic counselors and metabolic disease specialists may also be able to recommend a center in your areas.

How children with Duchenne or Becker muscular dystrophy perform in school depends on many factors including when treatment began, how a child responds to treatment, the specific symptoms that develop, when symptoms develop and how severe a form of the disorder they have. Children who have neurological problems such as intellectual disability and learning difficulties will require special assistance in school. Children with Duchenne and Becker muscular dystrophies will be eligible for an individual education plan (IEP) or a 504 plan. An IEP is a document that helps to guide the education of a child with a disability or special needs. The plan is individualized for each student. A 504 plan ensures that students with disabilities can fully participate in school and have access to the same educational opportunities as all children. Parents are encouraged to provide a school with a packet of information on Duchenne and Becker muscular dystrophies and to work with school officials including teachers, nurses, psychologists, the principal, and other professionals.

The U.S. Department of Education has information on individual education plans and on 504 plans. Support groups like the Muscular Dystrophy Association or Parent Project Muscular Dystrophy (ThinkGenetic Partner) have lots of information and advice on how to handle school for all age levels.

Duchenne muscular dystrophy is estimated to affect about 1 in 3,500 live male births. Becker muscular dystrophy is estimated to affect anywhere from 1 in 18,000 to 1 in 31,000 live male births. Between 400 and 600 boys are born with these disorders in the United States each year.

Children with infantile Duchenne or Becker muscular dystrophy may need lots of different medical equipment. Parents may need to get a braces, canes, a pediatric wheelchair, strollers, assistive breathing device, adaptive chairs, and shower chairs to name just a few. These devices can be expensive. Certain support groups and nonprofits provide support for medical equipment. The Muscular Dystrophy Foundation runs a National Equipment Program. If families have equipment they no longer need, the organization arranges for that equipment to go families who need it. The organization also provide links to other resources, including government organizations, that can help people get needed medical equipment. A doctor or other medical specialist can work with families to get or advocate for medical equipment for children with Duchenne or Becker muscular dystrophy.

People with Duchenne or Becker muscular dystrophy may have lung problems. These disorders can affect the muscles that the body needs to breath properly. People with DMD or BMD may have difficulty breathing and coughing. These problems tend to occur after they can no longer walk and need to use a wheelchair. People with these disorders are at risk for respiratory infections because they cannot cough effectively. Coughing helps to clear secretions and mucus from the airways. A minor respiratory infection can develop into pneumonia. Respiratory or chest infections should be promptly and aggressively treated with antibiotic. They may need help coughing. Some people may be taught manual ways to help clear their airways, or they may have to use a cough assist machine. This machine helps people clear secretions from the breathing tubes.

Some teenagers with DMD may have trouble breathing at night. They may need a machine to help them breath when they sleep. Two types of machines may be recommended: a bilevel positive airway pressure or BiPAP machine, or a continuous positive airway pressure (CPAP) machine. Some people may eventually need help breathing during the day. Doctors may recommend that some people whose breathing problems become very bad get a tracheostomy. This is a procedure in which an opening is created in the throat and a small tube is inserted to assist with breathing.

People with DMD or BMD should have their lung function assessed before undergoing surgery. Doctors, patients and family members should be aware of signs of decreased lung function. These signs include chest or respiratory infections that won’t go away or persist, being sleepy all day, lack of energy, frequent headaches especially in the morning, trouble sleeping, always feeling like they have to catch their breath, or trouble paying attention.

Carriers for Duchenne or Becker muscular dystrophy need to monitor their heart health. Carriers may be at risk of developing heart muscle disease (cardiomyopathy). They should receive a full heart work up when they are first confirmed as being carriers for one of these disorders. In 2005, the American Academy of Pediatrics published recommendations for monitoring the heart in people with these disorders. For carriers, these recommendations state that they should be screened with a complete cardiac evaluation at a minimum of every 5 years starting at 25 to 30 years of age.

Duchenne and Becker muscular dystrophies are always caused by an unexpected change, called a mutation, in a gene called DMD. People have about 20,000-25,000 genes in their bodies. Our genes contain our body’s genetic information, called DNA. Genes are like our body’s instruction manual – they control the growth, development and normal function of the body. When a mutation happens in a gene, the gene cannot work properly. It is like a section of the body’s instruction manual is not correct, and it causes problems with the normal development and functioning of the body. A mutation in the DMD gene is the only gene change known to cause Duchenne and Becker muscular dystrophies.

Women who are "carriers" usually do not experience symptoms of Duchenne or Becker muscular dystrophies, but sometimes women can experience muscle weakness and they may have an increased risk for developing disease of the heart muscle (cardiomyopathy). In specific instances, girls and women may experience any or all of the associated symptoms just like boys and men do.

A small percentage of women with Duchenne or Becker muscular dystrophy will develop muscle weakness, particularly in the arms, legs, and back. Generally, this weakness is milder than seen in boys and men with these disorders and progresses more slowly. Muscle pain and cramps may also occur. In women, these symptoms may not appear until adulthood. These women may be at a greater risk for developing weakness of the heart muscle. This may be first seen as shortness of breath or exercise intolerance. As with boys and men, cardiomyopathy can lead to heart failure. Some women may only have heart issues.
Sometimes, women or girls can develop symptoms that are as severe as those seen men or boys with these disorders.

Duchene and Becker muscular dystrophies are passed through families in an X-linked inheritance pattern, meaning the DMD gene that causes these disorders is located on the X-chromosome. Women have two copies of the X chromosome (XX) and men have one copy of the X chromosome and one copy of a Y chromosome (XY). If men inherit an X chromosome containing the nonworking or "faulty" DMD gene, they are unable to produce a protein called dystrophin. Without this protein, muscle fibers are damaged through normal use, which results in progressive muscle weakness and deterioration. On the other hand, if women inherit an X chromosome with a nonworking or "faulty" DMD gene they have a second backup X chromosome with a working DMD gene that can produce some dystrophin. Women who are "carriers" for Duchenne and Becker muscular dystrophy usually do not develop symptoms because they had a normal second copy of the gene. However, not all women are just carriers and some can and do have health problems related to these disorders. In some instances, a woman can have health problems as severe as their male relatives. Since woman who carry one copy of nonworking gene can have symptoms, it is important that they discuss Duchenne or Becker muscular dystrophy with their doctor and obtain appropriate referrals to monitor their health.

Some people with Duchenne or Becker muscular dystrophy may find it challenging when it’s time to move (transition) from pediatric to adult health care services. One big change is leaving a doctor with whom you have a long-standing relationship, a doctor who is familiar with both your condition and you. It can feel like ‘starting over’ as you’ll begin to work with new doctors and a new medical team. Another challenge in moving to adult care is that young adults must take greater responsibility for their health. They must manage their disorder and manage their medications. They must bear greater responsibility for decisions concerning their health. If possible, adolescents should be encouraged to make decisions about their care as early as possible to make this transition easier. Some hospitals have programs to help children with chronic disease transition to adult care services.

In addition to talking with doctors and healthcare providers about helping or transitioning a teen with Duchenne or Becker muscular dystrophy to a point where they can take charge of their medical care and move to adult doctors, there is information and resources available from the Muscular Dystrophy Association’s transition center and the Muscular Dystrophy association in the UK. Parent Project Muscular Dystrophy (ThinkGenetic Partner) is also developing tools to help parents and teens make this change as well.

Duchenne and Becker muscular dystrophy are related disorders. They are caused by different genetic changes in the DMD gene. This gene produces a protein called dystrophin that is active in skeletal, smooth, and cardiac muscle. In Duchenne muscular dystrophy, there is virtually no dystrophin in the body; in Becker muscular dystrophy the protein is present, but only partially functional.

Collectively, these disorders may be classified as dystrophinopathies. Dystrinopathies are a group of disorders caused by genetic changes to the dystrophin gene. These changes lead to a lack of dystrophin or the production of only partially effective dystrophin.

Duchenne muscular dystrophy is also known muscular dystrophy, Duchenne type or DMD.

Becker muscular dystrophy is also known as muscular dystrophy, Becker type or BMD.

Supportive therapies can be used to treat specific symptoms of Duchenne or Becker muscular dystrophy. This can include physical therapy to build muscle strength, promote mobility, and prevent contractures; canes, braces, and wheelchairs to aid with walking; surgery to treat scoliosis or contractures; and devices that assist individuals with breathing; medications to help with heart disease. There are more supportive therapies that may be recommended based on an individual’s specific symptoms. Parent Project Muscular Dystrophy offers a guide for families discussing both diagnosis and management of Duchenne muscular dystrophy. It is titled, The Diagnosis and Management of Duchenne Muscular Dystrophy: A Guide for Families. The Muscular Dystrophy Association and other support groups also have extensive information on treatment for these disorders.

There are many support groups or organizations for Duchenne muscular dystrophy that provide support, information, advice, referrals to physicians and medical centers, and up-to-date information on research and treatments. Many of these groups also fund research. Support groups for Duchenne and Becker muscular dystrophies, include: