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in the diagram below to find out more.
There is never a good time to find out that your child or loved one has Duchenne. However, an early diagnosis gives your family the best possible opportunity to access care and support so you can:
Learn why genetics plays an important role in Duchenne.
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in the list below to find out more.
Learn how a genetic counselor can help your family.
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If Duchenne is suspected, the first thing your family doctor will do is perform a physical exam to check for muscle weakness.
They will also ask about delays in early developmental milestones, such as sitting, walking and standing up from the floor.
Learn more about Duchenne signs and symptomsHigh CK levels in the blood do not automatically mean that your child or loved one has Duchenne. Genetic testing is the only way to confirm a Duchenne diagnosis.
If your child or loved one shows signs and symptoms of Duchenne, your doctor will usually recommend a special blood test called a CK test. This involves taking a small sample of blood which will be sent to a lab for analysis.
What is a CK test?
A CK test checks for an enzyme called creatine kinase, or CK. When muscle fibers are damaged, CK leaks out into the bloodstream. The muscle damage caused by Duchenne means that the level of CK in the blood will often be higher than normal.
Learn more about Duchenne signs and symptomsIf your doctor becomes concerned that your child or loved one needs further testing, they will usually refer them to a specialised center or neuromuscular specialist.
Specialists will then work through a careful diagnostic process to identify the cause of the symptoms and may recommend a variety of tests.
If your child or loved one has high CK levels, another sample of blood will be taken to test for changes in genes (called mutations) that cause Duchenne. These genetic tests may confirm or rule out Duchenne:
If your child or loved one DOES have Duchenne
Resources and therapies are available to help manage symptoms and possibly slow down the progression of the condition.
If your child or loved one DOES NOT have Duchenne
Your doctor will do more investigations into what else could be causing symptoms.
Different genetic tests can also tell your doctor about the type of mutation your child or loved one has. This is important because different mutations may be treated with different types of medication.
Figure adapted from
Haas, et al. 2015
Duchenne is a genetic disorder, which means that it is caused by changes (mutations) in a certain gene.
Genes are made up of DNA, a code that tells the cells in our body how to make proteins. Proteins are the building blocks of our bodies, and they are needed to make and replace cell.
In Duchenne, there is a mutation in the gene that codes for dystrophin – an important protein that helps to keep muscles working properly. As a result, the body cannot make dystrophin.
Without dystrophin, muscle cells are easily damaged.
Learn moreMost cases of Duchenne are caused when large pieces of the dystrophin gene are lost or deleted (’deletions’). Less often, large pieces of the dystrophin gene are copied or duplicated (‘duplications’). Duchenne can also be caused by smaller changes in the DNA code.
Figure adapted from Bladen 2015; Pichavant 2011; Kalman 2011
Although most treatment strategies can be used regardless of the genetic mutation, in some cases treatment specifically for a particular mutation may be available
The mutation in the gene that codes for dystrophin can be either:
Spontaneous mutations mean that sometimes Duchenne can occur without any family history of the disease. These new mutations can also be passed onto the next generation.
Figure adapted from Ciafaloni 2009
Duchenne is an X-linked disease, which means that the gene causing the disorder is located on the X chromosome
Adapted from the Muscular Dystrophy Association
*Carriers may show signs and symptoms of Duchenne and may need treatment
Adapted from the Muscular Dystrophy Association
The mutation occurs when the mother’s body makes the egg cell
If this particular egg cell is fertilized, the baby will carry a faulty dystrophin gene.
The mutation occurs at conception (when the mother becomes pregnant)
In this case, the baby will carry a faulty dystrophin gene.
This is because an affected father only passes a Y chromosome to his sons (the Duchenne-causing gene is located on the X chromosome). However, he will pass the Duchenne-causing gene onto his daughters, because each daughter inherits her father’s only X chromosome. These daughters will be carriers.
People have no choice in the genetic conditions that are passed on in a family. Nobody did anything wrong to cause Duchenne so there is no reason to blame yourself or others.
Normally, a female carrier does not show symptoms of Duchenne. This is because her healthy dystrophin gene will usually be able to produce enough of the dystrophin protein.
However, sometimes a carrier is unable to produce enough dystrophin. This means that she will experience some signs and symptoms, which can be treated in the same way as boys with Duchenne.
In all carriers, regular strength checkups and close heart monitoring are important to make sure that any symptoms that may arise are properly treated. This is why it is so important for female relatives of a boy with Duchenne to get tested to find out whether or not they are carriers.
Find out about how treatment can helpIf a woman is a Duchenne carrier, she may have another baby with Duchenne.
The chances of a carrier having a child with Duchenne are 1 in 4 (or 25%). This means that for every baby she has, there is a 1 in 4 chance that the child will have Duchenne.
If you have a child or relative with Duchenne, it is possible to offer prenatal diagnoses in future pregnancies through genetic testing.
Other women in the family can also find out if they are carriers of the condition. This will help them work out their chances of having a baby with Duchenne.
Once you have the results, you can talk about what they mean for your family with a genetic counselor.
Find out more about what to expect for the future Learn about Duchenne treatment optionsGenetic counselors are professionals who can help guide you through genetic tests and explain how the results might affect you or your family. They also provide you with emotional support and the resources to help you cope long-term.
They will answer any questions you have about Duchenne and what it means for your family
They will help determine the best testing strategy for your child or relative
They will help you make sense of the results and discuss the best course of action
They will help you and your family cope with a positive test result
Deciding whether to talk to your family members about a genetic diagnosis is a very personal decision.
But you are not alone.
A genetic counselor can help you:
The first physical symptoms of Duchenne may be hard to recognize, so it can be difficult to diagnose.
If you think your child or loved one might have Duchenne, take these 3 steps to help your doctor determine whether it is Duchenne or another medical condition.
Understanding your family's history of muscle disease and other conditions can help your doctor reach a diagnosis.
Write down any symptoms you have noticed. Not sure what signs to look for? Download the developmental milestone checklist here.
Bring photos or videos to help your doctor gain a better understanding of the signs and symptoms you have observed.
A discussion guide is available to support a conversation with your doctor