MDA leads the search for treatments and therapies for Becker muscular dystrophy (BMD). The Association also provides comprehensive supports and expert clinical care for those living with BMD.
In this section, you’ll find up-to-date information about Becker muscular dystrophy, as well as many helpful resources. This information has been compiled with input from researchers, physicians and people affected by the disease.
As you learn more about BMD, always remember that you’re not alone. MDA is here for you and your family, standing ready to provide help and hope. There is a place for you in the MDA BMD community.
MDA provides support by:
Once you sign up with your local MDA office , you’ll begin receiving MDA’s quarterly Quest  magazine, where you’ll find news about research and health care, helpful products and devices, social and family issues, and more.
In addition, MDA will keep you informed through e-alerts, educational publications and speakers, seminars, videos and newsletters.
Please know that there’s a role for you in the fight against Becker muscular dystrophy. The MDA community is strong and dedicated, with opportunities for involvement at all levels, such as:
Please know that there’s an important role for every member of the BMD community. We urge you to contact your local MDA office  to learn more.
A BMD diagnosis doesn’t mean an end to your hopes and dreams. Changes, challenges and adaptations lay ahead, but also opportunity, fulfillment, joy and hope for a future free of Becker muscular dystrophy.
Never forget that MDA is here to help.
|Becker muscular dystrophy affects the muscles of the hips, pelvic area, thighs and shoulders, as well as the heart.|
Becker muscular dystrophy (BMD) is one of nine types of muscular dystrophy, a group of genetic, degenerative diseases primarily affecting voluntary muscles. It is named after German doctor Peter Emil Becker, who first described this variant of Duchenne muscular dystrophy (DMD)  in the 1950s. BMD is similar to DMD but allows the voluntary muscles to function better than they do in DMD. The heart muscle, however, can be affected similarly to the way it is in DMD.
BMD's onset is usually in late childhood or adolescence, and the course is slower and less predictable than that of DMD. Generalized weakness first affects muscles of the hips, pelvic area, thighs and shoulders. Calves are often enlarged. There can be significant heart involvement. For more, see Signs and Symptoms .
Until the 1980s, little was known about the cause of any kind of muscular dystrophy. In 1986, MDA-supported researchers identified the gene that, when flawed — a problem known as a mutation — causes DMD and BMD. In 1987, the protein associated with this gene was identified and named dystrophin.
Genes contain codes, or recipes, for proteins, which are important biological components in all forms of life. BMD occurs when the dystrophin protein that's made from a particular gene on the X chromosome is only partially functional.
While DMD mutations cause virtually no functional dystrophin to be made, people with BMD make dystrophin that is partially functional. They make a shortened form of the protein, which protects the muscles of those with Becker from degenerating as completely or as quickly as those of people with DMD.
BMD primarily affects boys and men, who inherit the disease through their mothers. Women can be carriers but usually exhibit no symptoms. For more about the way gene mutations cause Becker dystrophy, see Causes/Inheritance .
Most people with BMD survive well into mid- to late adulthood. For more about living with BMD, see Medical Management . If the cardiac aspects of the disease are minimal, or if they are adequately controlled through medical intervention, a normal or nearly normal life span can be expected.
Researchers are actively pursuing several strategies in BMD. Among the major strategies are gene replacement; gene modification; stem cells; inhibiting a protein called myostatin; expanding the distribution and increasing the level of a protein called utrophin; and increasing blood flow to muscles.
MDA is supporting research in several of these areas. Human trials are under way for some of these strategies. For details, see Research .
Each of the 14 expert presentations made at the 2012 Becker Muscular Dystrophy Conference is available for viewing online. See BMD Conference Videos Cover Health Care, Research and Daily Living  to learn more.
The pattern of muscle loss in BMD usually begins with the hips and pelvic area, the thighs and the shoulders. To compensate for weakening muscles, the person may walk with a waddling gait, walk on his toes or stick out the abdomen.
The rate of muscle degeneration varies a great deal from one person to another. Some men require wheelchairs by their 30s or later, while some manage for many years with minor aids, such as canes.
Because muscular dystrophy doesn’t affect nerves directly, touch and other senses remain normal, as does control over the smooth, or involuntary, muscles of the bladder and bowel, and sexual functions.
Muscle deterioration in BMD usually isn’t painful in itself. Some people report muscle cramps at times; these usually can be treated with over-the-counter pain relievers.
Like muscles in the limbs, heart muscles also can be weakened by lack of dystrophin. People with BMD often develop cardiomyopathy — heart muscle weakness — because of a deficiency of dystrophin. The muscle layer (myocardium) of the heart deteriorates, just as the skeletal muscles do.
Damage done by BMD to the heart can become life-threatening as early as the teen years, and some people with BMD have mild skeletal muscle involvement but severe cardiac problems. For these reasons, everyone with BMD should be monitored by a cardiologist. See the Medical Management  section for more information on managing heart problems in BMD.
To view a presentation by cardiologist Elizabeth McNally about the heart in BMD, see the August 2012 video Cardiac Complications and Management in BMD .
Respiratory muscles often stay strong in BMD for many years, but eventually, they may become weaker than is optimal for breathing and coughing (to clear secretions from the respiratory tract).
To view a presentation by pulmonary medicine specialist Lisa Wolfe at Northwestern University in Chicago, see the August 2012 video Lung Health in Neuormuscular Disease .
Doctors believe that dystrophin abnormalities in the brain  may cause subtle cognitive and behavioral deficits. The learning problems seen in some people with BMD seem to occur in three general areas: attention focusing, verbal learning and memory, and emotional interaction. For more on coping with intellectual effects, see Medical Management .
The diagnosis of Becker muscular dystrophy (BMD) may be made during childhood, typically after the age of about 7. Sometimes, however, it isn’t made until adolescence or even adulthood, possibly when a young man finds he can’t keep up in physical education classes or military training.
In diagnosing any form of muscular dystrophy, a doctor usually begins by taking a patient and family history, and performing a physical examination. Much can be learned from these, including the pattern of weakness. The history and physical go a long way toward making the diagnosis, even before any complicated diagnostic tests are done.
The doctor also wants to determine whether the patient’s weakness results from a problem in the muscles themselves or in the nerves that control them. Problems in the muscle-controlling nerves, or motor neurons (originating in the spinal cord and brain and reaching out to all the muscles), can cause weakness that looks like a muscle problem but really isn’t.
Other diseases have some of the same symptoms as BMD, and it has sometimes been misdiagnosed as Duchenne muscular dystrophy (DMD)  or limb-girdle muscular dystrophy (LGMD) . For this reason, it’s important to go through a careful diagnostic process, usually involving genetic (DNA) testing, before making an assumption that the disorder is BMD.
Early in the diagnostic process doctors often order a special blood test called a CK level . CK stands for creatine kinase, an enzyme that leaks out of damaged muscle. When elevated CK levels are found in a blood sample, it usually means muscle is being destroyed by some abnormal process, such as muscular dystrophy or inflammation. Therefore, a high CK level suggests that the muscles themselves are the likely cause of the weakness, but it doesn’t tell exactly what the muscle disorder might be.
DNA testing of the dystrophin gene to diagnose BMD is now widely available and is usually done from a blood sample. In many cases, the DNA test alone can tell families and doctors with a fairly high degree of certainty whether the disease course is more likely to be BMD or Duchenne muscular dystrophy (DMD). You can ask your MDA clinic  physician or genetic counselor what tests are available. For more on getting a definitive genetic diagnosis, see The Genie's Out of the Bottle: Genetic testing in the 21st century .
Female relatives of men and boys with BMD  can undergo DNA testing to see if they are carriers of the disease. If they are, they can give birth to children who are themselves carriers or who will develop BMD.
To view a presentation by a genetic counselor, see the August 2012 video Genetics of BMD: Why Your Mutation Matters .
In some cases, to be more certain about the disease and its course, a doctor may suggest a muscle biopsy  in which a small sample of muscle is taken for special examination. Muscle biopsies also may be taken as part of a research study.
|Muscles are made up of bundles of fibers (cells). A group of interdependent proteins along the membrane surrounding each fiber helps to keep muscle cells working properly. When one of these proteins, dystrophin, is absent, the result is Duchenne muscular dystrophy; poor or inadequate dystrophin results in Becker muscular dystrophy.|
|Diseases inherited in an X-linked recessive pattern mostly affect males, because a second X chromosome usually protects females from showing symptoms.|
In 1986, MDA-supported researchers identified the gene that, when flawed, or mutated, causes both Becker and Duchenne  muscular dystrophies. In 1987, the protein associated with this gene was identified and named dystrophin.
Genes contain codes, or recipes, for proteins, which are important biological components in all forms of life. BMD occurs when a particular gene on the X chromosome fails to make sufficient levels of the protein dystrophin. Dystrophin plays a role in keeping muscle cells intact; lack of dystrophin causes cells to be fragile and easily damaged.
In BMD, dystrophin is produced, but it's a shortened form and is only partially functional. Because of the partially functional dystrophin, muscles don't degenerate as badly or as quickly in BMD as they do in DMD, in which virtually no functional dystrophin is made.
Bewildered parents often ask, “But it doesn’t run in the family, so how could it be genetic?”
BMD can run in a family, even if only one person in the biological family has it. This is because of the different ways in which genetic diseases are inherited.
BMD is inherited in an X-linked pattern. That means the gene that sometimes contains a mutation causing these diseases 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. Girls get two X chromosomes, one from each parent. Each son born to a woman with a dystrophin mutation on one of her two X chromosomes has a 50 percent chance of inheriting the flawed gene and having BMD. Each of her daughters has a 50 percent chance of inheriting the mutation and being a carrier.
Carriers usually have no disease symptoms but can have a child with the mutation or the disease. BMD carriers are at risk for cardiomyopathy (see Signs and Symptoms ).
How can a family with no history of BMD suddenly produce a child with the disease? There are two possible explanations:
If a mother gives birth to a child with BMD, there’s always the possibility that more than one of her egg cells has a dystrophin gene mutation, putting her at higher-than-average risk for passing the mutation to another child. Once the new mutation has been passed to a son or daughter, he or she can pass it to the next generation.
A man with BMD can’t pass the flawed gene to his sons because he gives a son a Y chromosome, not an X. But he’ll certainly pass it to his daughters, because each daughter inherits her father’s only X chromosome. They’ll then be carriers, and each of their sons will have a 50 percent chance of developing the disease, and so on. A good way to find out more about the inheritance pattern in your family is to talk to your MDA clinic physician or a genetic counselor.
Why don’t girls usually get BMD? When a girl inherits a flawed dystrophin gene from one parent, she usually also gets a healthy dystrophin gene from her other parent, giving her enough of the protein to protect her from the disease. Males who inherit the mutation get the disease because they have no second dystrophin gene to make up for the faulty one.
However, although girls don’t usually get the full effects of BMD, some females with the gene flaw are somewhat affected. A minority of females with the mutation are manifesting carriers , who usually have a mild form of the disorder.
For these women, the dystrophin deficiency may result in weaker muscles that fatigue easily in the back, legs and arms. Some may even need a wheelchair or other mobility aids. Manifesting carriers may have heart problems, which can show up as shortness of breath or inability to do moderate exercise. The heart problems, if untreated, can be quite serious, even life-threatening.
A female relative of someone with BMD can get a full range of diagnostic tests to determine her carrier status. If she's found to be a carrier, regular strength evaluations and close cardiac monitoring can help her manage any symptoms that may arise.
Thanks to general medical advances, particularly in cardiology, people with Becker muscular dystrophy (BMD) are living longer in the 21st century than in previous decades. As of 2011, most therapies are supportive in nature, although truly disease-modifying therapies are the subject of intense research.
MDA clinic  physicians can provide referrals to specialists and therapists for these forms of care. The use of available therapies can help maintain comfort and function and prolong life expectancy.
To view a presentation on medical management of BMD by pediatric neurologist Brian Tseng, see the August 2012 Taking the Reins of Your Medical Care and Participating in Clinical Trials .
People with BMD may have unexpected adverse reactions to certain types of anesthesia . It's important that the surgical team know about that the patient has BMD so that complications can be avoided or quickly treated.
Back to top 
Braces, also called orthoses, can support just the ankle and foot or extend over the knee. Ankle-foot orthoses are sometimes prescribed for night wear to keep feet from pointing downward and keep the Achilles tendon stretched. (Orthoses also are known as orthotics.)
To view an August 2012 video presentation on this topic, see Functional Treatment Considerations: Orthotics .
Some people with BMD ultimately require wheelchairs or scooters. Although some look at these devices as symbols of disability, most users find they're actually more mobile, energetic and independent when using a wheelchair than when trying to walk on very weak legs. Scooters and wheelchairs are especially valuable when covering long distances.
To view a presentation by an occupational therapist, see the August 2012 video Functional Treatment Considerations: Occupational and Physical Therapy. 
Back to top 
Cardiomyopathy , which means deterioration of the heart muscle, is common in Becker MD. The American Academy of Pediatrics recommends  that those with BMD have cardiac evaluations at least every other year beginning at age 10.
Carriers of BMD  also are at higher-than-average risk of developing cardiomyopathy. The Academy suggests that carriers should undergo a complete cardiac evaluation in late adolescence or early adulthood, or sooner if symptoms occur, and should be evaluated every five years starting at age 25 to 30.
Some people with BMD who have cardiomyopathy but generally good health have been successfully treated with heart transplants.
Back to top 
As muscle deteriorates, a person with muscular dystrophy often develops fixations of the joints, known as contractures. If not treated, these can become severe, causing discomfort and restricting mobility and flexibility. The impact of BMD can be significantly minimized by keeping the body as flexible, upright and mobile as possible.
There are several ways to minimize and postpone contractures. Range-of-motion exercises , performed on a regular schedule, help delay contractures by keeping tendons from shortening prematurely. It’s important that a physical therapist demonstrate the correct way to do range-of-motion exercises.
Braces on the lower legs help keep the limbs stretched and flexible, delaying the onset of contractures.
When contractures have advanced, surgery may be performed to relieve them. A tendon release procedure, also called heel cord surgery , can treat ankle and other contractures while the child is still walking.
Back to top 
No special dietary restrictions or additions are known to help in BMD. Most doctors recommend a diet similar to that for any growing boy, but with a few modifications.
A combination of immobility and weak abdominal muscles can lead to severe constipation, so the diet should be high in fluid and fiber, with fresh fruits and vegetables dominant.
For boys and men who use power wheelchairs, aren’t very active or who take prednisone , excessive weight gain can occur. Caloric intake should be restricted to keep weight down, as obesity puts greater stress on already weakened skeletal muscles and the heart. Doctors have found that a low-calorie diet doesn’t have any harmful effect on the muscles.
Those on prednisone and those with cardiomyopathy may require a sodium-restricted diet.
Back to top 
Exercise can help build skeletal muscle, keep the cardiovascular system healthy and contribute to feeling better. But in muscular dystrophy, too much exercise could damage muscle. Consult with your doctor about how much exercise is best. A person with BMD can exercise  moderately but shouldn’t go to the point of exhaustion.
Some experts recommend swimming and water exercises (aquatic therapy) as a good way to keep muscles as toned as possible without causing undue stress on them. The buoyancy of the water helps protect against certain kinds of muscle strain and injury.
Before undertaking any exercise program, make sure to have a cardiac evaluation.
Back to top 
Dystrophin deficiency can cause some cognitive problems  in some people. Children and adults with BMD who are suspected of having a learning disability can be evaluated by a neuropsychologist through a school system’s special education department, or at a medical center with a referral from the MDA clinic .
If a learning disability  is diagnosed, educational and psychological interventions can begin right away. The specialist may prescribe exercises and techniques that can help improve these deficits, and schools can provide special help with learning.
Back to top 
Medications that lessen the workload on the heart are sometimes prescribed for BMD. There’s some evidence that treatment with angiotensin converting enzyme (ACE) inhibitors and beta blockers can slow the course of cardiac muscle deterioration  in BMD if the medications are started as soon as abnormalities on an echocardiogram (imaging of the heart) appear, but before symptoms occur.
Medications belonging to a group known as corticosteroids have been found effective  in slowing the course of Duchenne muscular dystrophy. Data for or against the use of corticosteroids in BMD are lacking. However, some physicians prescribe corticosteroids for severe BMD in much the same way as they would for DMD, if the patient or family wants to try this type of medication.
Prednisone is by far the most commonly prescribed corticosteroid for DMD/BMD in the United States. When taking at relatively high doses for long periods of time, it can have significant side effects, such as weight gain, decreased bone density, behavioral abnormalities, cataracts and growth retardation.
Back to top 
The primary goals of physical therapy are to allow greater motion in the joints and to prevent contractures and scoliosis (spinal curvature). Occupational therapy focuses on specific activities and functions, such as work tasks, recreation, driving, dressing or using a computer.
For an August 2012 video on this topic, see Functional Considerations: Occupational and Physical Therapy .
Back to top 
In some people with BMD, particularly as they age, breathing muscles can weaken, resulting in less than optimal breathing, particularly during sleep. This can be treated by a noninvasive strategy known as bilevel positive airway pressure. Coughing muscles also can become weak, allowing mucus to build up in the respiratory tract, which can lead to obstruction and infection. A device known as a CoughAssist can help with this problem.
To see a presentation by a pulmonary medicine specialist, see the August 2012 video Lung Health in Neuromuscular Disease .
Back to top 
MDA-supported investigators are actively pursuing several approaches to halt or reverse the muscle damage caused by Becker muscular dystrophy.
Some of the front-running strategies include: inserting new dystrophin genes; changing the way cells interpret genetic instructions for dystrophin; changing the mutated dystrophin gene itself; manipulating other proteins in the body to compensate for the lack of dystrophin; increasing blood flow to muscles; and using stem cells to repair damaged muscles.
Some studies are focused specifically on the dystrophin-deficient heart.
Flaws in the dystrophin gene cause Duchenne muscular dystrophy (DMD) , as well as the less severe Becker muscular dystrophy (BMD), so many of the strategies being tried in DMD also apply to BMD.
For more, see these 2012 videos on BMD research: Preclinical Testing in Animal Models of Muscular Dystrophy  and From Targets to Clinical Trials in Becker Muscular Dystrophy .
Researchers are pursuing a number of strategies to sustain or improve heart function in BMD and DMD. They're testing existing medications for their possible benefits in the BMD/DMD-affected heart, and conducting basic research to understand and find new approaches to treating the heart in these diseases.
Understanding and treating dystrophin-deficient cardiomyopathy  (cardiac muscle abnormalities) is a priority for MDA. The MDA DMD Clinical Research Network has made studying the natural history and treatment of this condition a primary focus. In addition, MDA sponsored a meeting of more than 40 leading clinicians and researchers from the United States and Europe in January 2011 to discuss optimal clinical care of the DMD/BMD-affected heart .
In 2009, scientists found that dystrophin gene mutations that cause cardiomyopathy in BMD  affect specific regions of the dystrophin protein, not necessarily the same regions associated with skeletal muscle loss. The study will allow better prediction of cardiomyopathy in BMD and earlier consideration of cardioprotective treatments in this disease, as well as giving researchers insight into which parts of the dystrophin protein are essential to preserve when shortened dystrophin molecules are being considered as therapeutic strategies.
The drug sildenafil (Viagra) has been found to impart cardioprotective effects in mice  with both an early- and late-stage DMD-like disease. Sildenafil, which is used to treat erectile-dysfunction, belongs to a class of drugs called phosphodiesterase 5 (PDE5) inhibitors, which relax the smooth muscles lining blood vessels, increasing blood flow to muscles and the heart. The cardiac effects of sildenafil in teens and men with DMD  are being studied.
Laboratory studies have found that an experimental compound designed to help seal cell membranes, p188, benefited heart function in dystrophin-deficient dogs .
In 2011, MDA-supported researchers found that inhibiting the action of a protein called NF-kappa B  improved cardiac function in mice with a severe DMD-like disease.
Back to top 
Although still in very early stages of development, repair of the dystrophin gene  at the DNA level shows promise. This strategy is aimed at helping cells permanently repair errors in the dystrophin gene, fixing the underlying cause of DMD.
In experiments on cultured cells and in mice with flawed dystrophin genes, "designer" gene-repair molecules stimulated DNA repair levels more than 10 times greater than those achieved by a previous class of targeting molecules. The muscle cells containing rejuvenated dystrophin genes successfully produced normal dystrophin protein at levels consistently higher than muscle cells treated with the older-generation molecules.
Although the results so far have been encouraging, the frequencies of gene repair are in the 1 to 5 percent range — too low to be considered therapeutically relevant. And, for now, the gene repair strategy is limited to correcting "single-letter" errors (point mutations) in a gene.
Work must be done before this technique can progress to human trials, including refinement of the targeting molecules, studies to determine the most effective delivery methods, and testing in different animal models.
Back to top 
Gene therapy, or gene transfer, refers to the delivery of genes as therapeutic agents. Since genes carry the instructions for protein synthesis, they can lead to production of proteins that are directly or indirectly therapeutic in neuromuscular diseases. Because transferred genes potentially can continue to produce protein for some time, gene therapy may offer a more permanent fix than other therapies. But gene therapy faces many technical challenges, as well as a high bar set by regulatory agencies like the U.S. Food and Drug Administration (FDA).
The key challenges are delivering the genes to the targeted tissue while avoiding off-target tissues, and avoiding unwanted immune response to the proteins made from the new genes, or to the delivery vehicles in which the new genes are delivered.
MDA-supported scientists have created a miniaturized, working dystrophin gene that has been tested in boys with DMD. Although the treatment appeared to be safe, some of the boys experienced an unwanted immune response to the dystrophin protein  that limited the effectiveness of the gene transfer. This immune response is undergoing further investigation .
Blocking the myostatin protein via a protein called follistatin is a strategy that has potential for treating DMD and likely many other neuromuscular diseases. Mice with a DMD-like disease that received genes for the follistatin protein showed an overall increase in body mass and weight of individual muscles. Monkeys that received follistatin gene transfer  had stronger, larger muscles.
Back to top 
Experiments have shown that, when dystrophin is missing from the muscle-fiber membrane, it causes another protein, known as nNOS, to be missing as well, and that this results in an inability of blood vessels supplying muscles to adequately dilate during exercise. When nNOS-deficient mice were treated with a phosphodiesterase inhibitor, which dilates blood vessels, their exaggerated fatigue response to exercise  was eliminated. Phosphodiesterase inhibitors are a class of drugs that include sildenafil (Viagra) and tadalafil (Cialis), both used to treat erectile dysfunction.
Other investigators found that treatment with sildenafil significantly improved heart function in mice missing the dystrophin protein.
On the basis of these and other findings, researchers have started investigating the possibility that phosphodiesterase inhibitors can improve skeletal-muscle or heart-muscle function in people with BMD or DMD.
In 2010, an MDA-supported trial testing the effects of tadalafil  on blood flow to muscles began in men with BMD.
Other trials of phosphodiesterase inhibitors also are under way to test their effects on skeletal-muscle and heart-muscle function in DMD and BMD.
Back to top 
A strategy that has received considerable MDA support involves inhibiting the actions of a naturally occurring protein called myostatin , which limits muscle growth. Researchers hope that blocking myostatin may allow muscles to grow larger and stronger.
Inhibitors of myostatin have received much attention from the neuromuscular disease research community ever since it was found several years ago that people and animals with a genetic deficiency of myostatin appear to have large muscles and good strength without apparent ill effects. In 2010, a study showed that mice lacking dystrophin and showing a DMD-like disease benefited from treatment with a "decoy" that lured myostatin away from their muscles .
The biotechnology company Acceleron Pharma  then developed a drug based on this decoy and began testing it, with MDA support, in boys with DMD. Unfortunately, unexpected safety issues  arose during that trial, causing Acceleron to terminate it in 2011.
The company hopes to resolve these safety issues and resume testing ACE-031, or a modified version of ACE-031.
Other strategies to inhibit myostatin, such as injecting genes for the myostatin-blocking follistatin, also are under consideration.
Back to top 
MDA scientists are using stem cells  (cells from which specialized cells "stem") isolated from muscle, blood vessels or bone marrow to regenerate muscles in dystrophin-deficient laboratory animals.
Stem cells are cells in the very early stages of development. They may be destined to turn into a specific cell type (such as muscle or nerve cells), or they may still retain pluripotency — the ability to develop into any of a number of different cell types.
In 2006, MDA-supported researchers restored mobility to two dogs and stabilized function in a third  using stem cells taken from muscle blood vessels.
In a study reported in 2007, a European research group successfully used a combination of genetic correction and stem cells to treat DMD research mice . The researchers in this study extracted muscle-generating stem cells from muscle tissue and blood in people with DMD, corrected the genetic error in the cells' dystrophin genes, and then injected the cells into dystrophin-deficient mice. The muscle-derived cells gave rise to better muscle regeneration than did the blood-derived cells.
In 2010, MDA-supported scientists in France reported they had identified a previously unknown type of muscle stem cell  located in the spaces between muscle fibers in mice. Although still in the early stages of research, it's hoped the new cells, dubbed PICs, may play an important a role in muscle regeneration and repair.
Scientists reported in 2010 that formation of new muscle tissue  first requires a controlled type of DNA damage. The new finding increases scientists' understanding of how immature muscle cells become muscle and could help them manipulate this process to treat several forms of muscular dystrophy.
Stem cells continue to be a major area of investigation for MDA-supported researchers. Some are continuing to study muscle satellite cells , a type of stem cell present in muscle tissue. Others are studying different cell types that are capable of surviving transplantation  into muscle and producing the desired proteins. Still, others are studying the similarities and differences in the development of skeletal muscle and fat tissue .
Back to top 
In stop codon read-through, drugs target mutations known as premature stop codons (also called nonsense mutations), which tell the cell to stop making a protein — for instance, dystrophin — before it has been completely assembled. The drugs coax cells to ignore, or "read through," this improper stop signal. Premature stop codons in the dystrophin gene cause Duchenne muscular dystrophy (DMD) more often than they do BMD, but either disease is possible.
A company called PTC Therapeutics , in conjunction with Genzyme Corp. , and with some initial funding from MDA, developed an experimental stop codon read-through drug called ataluren for people with DMD or BMD due to a premature stop codon. In October 2010, PTC announced that a lower dose of ataluren appeared to work better  than a higher dose. In a clinical trial, those on lower dose walked an average of 29.7 meters (about 97 feet) more in six minutes than the high-dose or placebo groups (although all groups' walking distance declined over the course of the trial).
Another experimental drug designed to cause stop codon read-through of the dystrophin gene is known as RTC13. In 2011, MDA gave a three-year grant to Carmen Bertoni at the University of California, Los Angeles (UCLA) to develop RTC13 so it can be taken orally. By the end of the trial, RTC13 is expected to cause a lot of muscle cells to ignore premature stop codon (nonsense) mutations and produce dystrophin; and improve symptoms in dystrophin-deficient mice with a DMD-like disease.
Back to top 
Laboratory evidence shows that raising levels of the muscle protein utrophin can, to some extent, compensate for a deficiency of dystrophin.
Utrophin closely resembles dystrophin but, unlike dystrophin, is normally produced and entirely functional in BMD. Therefore, raising utrophin levels is unlikely to provoke an unwanted immune response, while raising levels of dystrophin may do so. Increasing utrophin production has the potential to help compensate for dystrophin deficiency regardless of the specific dystrophin gene mutation.
Although utrophin is close to dystrophin in both structure and function, there’s at least one key difference between the two proteins. During fetal development and perhaps a little beyond, utrophin is present all around the muscle fiber, interacting with clusters of proteins stuck in its surrounding membrane. As the animal or person matures, utrophin is replaced almost entirely by dystrophin, with one exception. At the neuromuscular junction, utrophin remains throughout life.
Several strategies are being tried to increase utrophin. One is to identify and suppress whatever is inhibiting utrophin production  — find the brake and release it, so to speak.
Another strategy is to inject a modified version of the utrophin protein  itself into the body. A 2009 study found that modified utrophin protein conferred significant benefits when injected into mice lacking the dystrophin protein and showing a disease resembling DMD.
Scientists reported in 2011 that systemically injecting the human form of a protein called biglycan  into mice with a disease resembling human DMD improved the resistance of mouse muscles to contraction-related damage; restored several proteins to their normal location at the muscle-fiber membrane; and recruited utrophin to the muscle-fiber membrane.
Back to top 
A clinical trial is a test in humans of an experimental medication or therapy. Clinical trials are experiments, not treatments, and participation requires careful consideration.
Although it's possible to benefit from participating in a clinical trial, it's also possible that no benefit — or even harm — may occur. Keep your MDA clinic  doctor informed about any clinical trial participation. (Note that MDA has no ability to influence who is chosen to participate in a clinical trial.)
For a more refined list of BMD clinical trials, visit ClinicalTrials.gov , a registry of federally and privately supported clinical trials in the United States and around the world. Select "Search for Clinical Trials," and follow the instructions to narrow down your search results.
It’s not likely that you’re reading this letter because you were searching the Web for someone to provide guidance for a student bound for college, or for a die-hard Bruce Springsteen fan in the “E Street Nation.” While we may share those traits in common, what is most likely is that — like me — you have found yourself to be a member of what I refer to as the “BMD Nation.”
When I was 9 years old, I learned I wouldn’t be living out my childhood dreams of playing shortstop for my beloved New York Mets. Instead, I learned I had Becker muscular dystrophy (BMD).
I’m now an adult with many personal and professional accomplishments behind me, and hopefully, many more to come, but when I first turned to MDA in 1976, the path forward was very unclear for my family.
The weeks and months of adjustment that follow a diagnosis of Becker muscular dystrophy differ for every family. In the decades that have passed since I first learned that BMD would be a part of my life’s journey, I’ve had the privilege of meeting many other families within our MDA BMD community. For each of them, their progression and adjustment experiences have varied. But what’s been constant is the shared sense of support they’ve gotten from MDA.
MDA’s community is here for you, both at home and around the world. Through your local MDA clinic, you’ll meet with health care professionals who are experts in muscle disease. Your local MDA office can help you access valuable community resources and stay in touch with other families and local events. MDA’s publications and online communities connect you with resources, world-renowned experts, and BMD-ers worldwide, while its advocacy program helps your voice be heard.
Most importantly, MDA-supported researchers are at the forefront of Becker muscular dystrophy research and are helping to drive the exciting progress being made in this disease.
The information that you’ll find on these BMD Web pages is designed to help you better understand its causes, symptoms, progression and care. Truly, knowledge is power, and the more you understand about this diagnosis, the more effectively you’ll be able to plan for a meaningful, productive future.
A BMD diagnosis means the future may look a little different than you had envisioned – but believe me, it is still full of promise.
For example, I’m University Dean for Student Affairs at the City University of New York (CUNY). Among my many activities are teaching, coaching basketball for Catholic Youth Organization, and serving on federal and state disability commissions. My younger brother, Gian, who also has Becker muscular dystrophy, is also a higher education professional.
Today, there are more opportunities than ever for people with disabilities to develop and use their abilities. Federal law guarantees a public education, equal employment opportunity and access to public places, while computers and other technology make life ever more accessible.
As you go forward in your journey with BMD, always remember that MDA is here to help — from medical care to summer camps to support groups to advocacy to the great hope of today’s BMD research. You are not alone.
Chris Rosa, Ph.D.
MDA National Task Force on Public Awareness
MDA National Board of Directors
To view a presentation by Chris Rosa, see the August 2012 video Transitional Freedom: From Consciousness to Culture to Comprehensive Care .