Duchenne muscular dystrophy is an inherited condition in which the body cannot make a muscle protein called dystrophin, so muscles are damaged by ordinary use and become progressively weaker, affecting movement, the heart and breathing [1,2].
This page provides general information. It does not replace advice from a doctor or another qualified healthcare professional.
A protein called dystrophin sits just inside the wall of each muscle fiber and cushions the strain of being stretched. In Duchenne muscular dystrophy the body makes almost no working dystrophin, so ordinary movement damages the fibers. Damaged fibers die and are replaced by scar tissue and fat, so the muscle weakens [1,2].
Three sets of muscles are involved. Movement muscles closest to the body, such as the hips and thighs, weaken first. The heart is a muscle too and is affected in almost everyone in time, and the breathing and coughing muscles weaken as well [1,9].
The condition belongs to a group called the dystrophinopathies, all caused by changes in the same gene. Becker muscular dystrophy is the milder form, where some partly working dystrophin is still made. Doctors separate the two by when a wheelchair becomes necessary: before age 13 in Duchenne and after age 16 in Becker muscular dystrophy [1]. Other muscular dystrophies involve different genes [3].
A review pooling 44 studies found about 19.8 cases per 100,000 live male births, close to 1 in 5,000 boys. It put the number of males living with the condition at about 7.1 per 100,000, and about 2.8 per 100,000 of the whole population [4]. Birth figures count new cases among babies born; the others count people alive at one time.
The authors add a warning: no study was rated high quality, and results varied so widely that the average is a rough guide only [4]. A United States surveillance program found 1.47 cases per 10,000 males aged 5 to 24 in 2007, with differences between areas larger than chance would explain [5].
All of these count people already diagnosed. Countries differ in how easily families reach a specialist and whether genetic testing is funded, so the figures cannot rank regions against each other.
Genes are instructions inside our cells. The DMD gene carries the instructions for dystrophin and sits on the X chromosome. Boys have one X chromosome and one Y, girls have two [2].
This is why the condition is called X-linked recessive. A boy has only one copy of the DMD gene, so a change in it leaves him no backup, while a girl’s second copy usually works, so she is generally well and is described as a carrier [2].
About two thirds of mothers of a boy with no family history carry the gene change themselves. In the rest it happened newly, around conception [1]. Nothing a parent did causes it.
Carriers are not always symptom-free. Around half have a raised muscle chemical in the blood, some have weakness or cramps, and there is a real chance of a heart muscle problem called dilated cardiomyopathy [1,28]. Girls very occasionally have the full condition, through unusual genetic situations [1].
Signs usually appear before age five [1]. Children walk a little late, at around 18 months on average, and parents most often notice general delay in movement, persistent toe-walking or late walking [1].
Common early features are [1]:
Without treatment, most children need a wheelchair before age 13, and curving of the spine is common once walking stops [1,9]. The heart is affected in almost everyone, often before symptoms appear: about a third of children show heart muscle changes by age 14 and effectively all after 18 [1,11]. Breathing muscles weaken too, showing first as a weak cough and disturbed sleep [12].
When to seek urgent help. Long-term corticosteroid treatment stops the body making its own stress hormone, so missing doses for more than a day, or a serious illness, injury or operation, can trigger a dangerous drop called adrenal crisis. Vomiting, drowsiness, confusion or collapse in someone taking steroids needs emergency care and an extra steroid dose, so carry a steroid card [13,14]. Contact the heart team promptly about new breathlessness at rest, swollen ankles or a sudden drop in energy [11], and get early help for a chest infection with a weak cough [12]. Tell every anesthetist and dentist about the diagnosis, since some anesthetic medicines can cause severe reactions [1].
A family doctor or pediatrician usually orders the first test after a parent raises a concern about walking or strength. It measures creatine kinase, a chemical that leaks from damaged muscle, which in this condition is more than ten times the normal level in everyone affected [1].
Genetic testing then confirms the diagnosis and identifies the exact change, which is needed later to work out which treatments could apply. It looks first for missing or repeated sections of the gene, then reads it in detail if nothing is found [1].
Diagnosis is still often late, at an average of about four years and ten months in boys with no family history in one long-standing figure and 41 months in a more recent study [1]. Early signs look like ordinary variation in how children develop.
In December 2025 the United States added the condition to its newborn screening recommendations, though each state decides when to start [27]. Testing is also offered to mothers and other female relatives, partly so anyone who carries the change can start heart checks [1].
There is no cure. Care combines medicines that slow muscle loss with close watching of the heart, lungs, spine and bones, led by an experienced team [8,9].
Corticosteroids. Prednisone, prednisolone and deflazacort all slow muscle loss, and a randomized trial found daily dosing worked better than a ten-days-on, ten-days-off pattern [15]. Side effects need managing, including weight gain, slowed growth, thinning bones and mood changes [1,15].
Two newer medicines. Vamorolone is a modified steroid, approved in the United States in October 2023 and in the European Union from December 2023 for children from age two. It appears to work about as well as standard steroids, with less effect on growth and bone, and work continues on how the two compare long term [16,17,29]. Givinostat is an oral medicine that is not a steroid, approved in the United States in March 2024 from age six and in the European Union for people aged six and over who can walk and already take a corticosteroid [18], and NICE recommended it in England in May 2026 [19].
Exon-skipping medicines. These patch over a faulty section of the gene so a shortened dystrophin can be made, and suit only particular gene changes. Four are approved in the United States, together applying to roughly a quarter to a third of people with the condition [20]. All were cleared on evidence of more dystrophin in muscle rather than proven benefit to how people function, a confirmatory trial in November 2025 missed its main goal, and regulators can withdraw approval granted this way [21]. None is authorized in the European Union.
Gene therapy. Delandistrogene moxeparvovec delivers a shortened dystrophin instruction into muscle in one infusion. It was approved in the United States in 2023 and widened in 2024 [24]. Its main trial missed its primary goal at one year, though several secondary measures favored treatment [22]. In 2025 two boys who could no longer walk died of acute liver failure after treatment. That November the United States regulator added its strongest warning, removed the license covering people who can no longer walk, and advised staying near a hospital for two months afterward [23]. European regulators gave a negative opinion in July 2025 [25]. Ataluren lost its conditional European authorization in 2025, after its effectiveness was not confirmed [26].
Heart, lungs, bones and spine. A heart specialist is involved from diagnosis, with a yearly heart trace and a scan that can show heart muscle scarring before symptoms appear, and ACE inhibitors or angiotensin receptor blockers usually start by about age ten even when tests look normal [9,11]. Breathing is monitored regularly, with techniques to expand the lungs and help coughing, then overnight and daytime support [9,12]. Physiotherapy, stretching, night splints and sometimes spinal surgery help joints and posture [1,8]. Availability differs sharply between countries.
Care works best when one neuromuscular team coordinates everything, and most families see physiotherapy, respiratory, cardiology, orthopedic and psychology services over time [8,10].
Practical arrangements make a large difference: school support, accessible buildings, help with writing, powered mobility and home adaptations [10]. Keep a steroid card and a note about anesthetic risks where a paramedic would find them [13]. Weight needs watching in both directions, since steroids can drive it up while swallowing difficulties can later drive it down, so a dietitian is often involved [8]. Gentle activity such as swimming keeps joints moving, while heavy resistance work is avoided [1].
The emotional side deserves the same care as the physical side, and anxiety and low mood are more common, in young people and in parents [1,10]. Mothers and sisters who carry the gene change should have a heart check in their late teens or early twenties and then every three to five years, even when they feel completely well [1,28].
Clinical trials test whether a treatment works and is safe. Duchenne muscular dystrophy is a very active research area, so studies come up regularly. Deciding is personal, and it helps to take it in steps.
Be clear on what a study involves:
Every trial has rules about who can take part, called eligibility criteria. Some describe who can join, others who cannot. For a Duchenne muscular dystrophy study they might include a genetically confirmed diagnosis, a particular type of gene change, an age range, still being able to walk or a set score on a timed movement test, a stable corticosteroid dose for months beforehand, heart or lung function above a threshold, and no previous gene therapy or recent spinal surgery.
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Study status checked: 3 August 2026. Research here moves quickly, and not every treatment named here is approved where you live. For current information, search at app.trialport.com.
In the United States, Parent Project Muscular Dystrophy publishes plain-language versions of the recommended standards of care, which many families use to prepare for appointments [11,12]. The Muscular Dystrophy Association offers clinic networks and equipment help, and CureDuchenne runs family education.
In the United Kingdom, Duchenne UK funds research and tracks treatment access decisions, and Muscular Dystrophy UK runs a helpline covering all muscle-wasting conditions [3].
Elsewhere, the World Duchenne Organization lists member organizations across many countries and is the most practical starting point. In Canada there is Muscular Dystrophy Canada, and in Australia Save Our Sons Duchenne Foundation. Coverage in parts of Asia, Africa, the Middle East and South America is thinner, and a specialist neuromuscular center or national rare disease alliance is usually the next best contact.
Can girls have Duchenne muscular dystrophy?
It is very rare. Girls usually have a second working copy of the gene, so carriers are generally well, although some have muscle symptoms and there is a raised chance of a heart muscle problem [1,28].
What is the life expectancy?
It has improved a great deal. Pooled figures put median survival at about 19 years where breathing support was not used and about 30 years where it was [6,7]. Averages describe groups, not individuals, and estimates built on care from earlier decades may understate what is possible now.
Is there a cure?
No. Treatment slows muscle loss and manages the effects on the heart, lungs, bones and spine [1,15,18].
Will exon skipping work for my child?
Only for particular gene changes. The four approved in the United States apply to roughly a quarter to a third of people, and the genetic report says which, if any, could suit. Their benefit to how people function is still debated [20,21].
Is gene therapy available where I live?
That depends on the country. It is licensed in the United States for people aged four and over who can still walk, with a strong warning about liver injury. European regulators gave a negative opinion in 2025 [23,25].
Can it be picked up at birth?
Increasingly, yes. The United States added the condition to its newborn screening recommendations in December 2025, though each state decides when to start [27]. Elsewhere it is not routine, and diagnosis usually follows a parent’s concern.
Written by: trialport editorial team
Reviewed by: Keith Berelowitz, Founder and CEO, trialport
Reviewed on: 3 August 2026
Next review due: 3 August 2027
References last checked: 3 August 2026