Muscular dystrophy is a group of genetic diseases affecting the skeletal muscles. These muscles attach to your bones and control movement. The form of muscular dystrophy depends on the specific gene mutation, or change, in your DNA. Each is associated with unique symptoms and has certain treatments. Keep reading to learn about six muscular dystrophy facts.

1. Muscular Dystrophy Is a Genetic Disorder

Muscular dystrophy develops in people with specific gene mutations. Your genes provide instructions to make proteins. When these instructions are changed, your cells can’t make the proteins correctly. Some people may not make any, while others make some but not enough.

Those with muscular dystrophy have mutations in genes that provide instructions for muscle proteins. Some people get the mutations from their parents. This is why it’s possible to have a family history of muscular dystrophy. Others develop mutations randomly.

Genes are found on structures called chromosomes. Humans have 46 chromosomes — 23 come from the mother and 23 from the father. One pair is the sex chromosomes, which are either X or Y chromosomes. The Muscular Dystrophy Association notes that people with two X chromosomes are biologically female. Those with an X and a Y chromosome are biologically male. Males inherit an X chromosome from their mother and a Y from their father.

Genes for certain muscle proteins are found on the X chromosome. If a male inherits an X chromosome from their mother with a mutated gene, they’ll have muscular dystrophy. This is known as an X-linked disease. X-linked muscular dystrophies include:

• Duchenne muscular dystrophy (DMD)
• Becker muscular dystrophy (BMD)
• Emery-Dreifuss muscular dystrophy (EDMD)

Other types of muscular dystrophy form from mutations on chromosomes that are not involved in determining sex — called autosomes. Autosomal dominant diseases develop when you have only one copy of a mutated gene from one parent, while autosomal recessive diseases require two mutated gene copies or one from each parent. Myotonic dystrophy and facioscapulohumeral muscular dystrophy (FSHD) are examples of autosomal dominant muscular dystrophy. The following types of muscular dystrophy can be both autosomal dominant and recessive:

• Limb-girdle muscular dystrophy (LGMD)
• Emery-Dreifuss muscular dystrophy
• Oculopharyngeal muscular dystrophy (OPMD)
• Distal muscular dystrophy (DD)

2. There Are Many Types of Muscular Dystrophy

Did you know that there are more than 30 types of muscular dystrophy? The most common type is DMD. The National Institute of Neurological Disorders and Stroke points out that DMD usually affects boys and starts developing in early childhood. Children with DMD have mutations in the dystrophin gene — which makes a protein that protects and holds muscle cells together. BMD is a milder form of DMD. People with BMD also have problems with their dystrophin gene. However, they can make a partially functional dystrophin protein. This means their disease isn’t as severe and doesn’t progress as quickly as DMD.

Not all types of muscular dystrophy are diagnosed in childhood. Myotonic dystrophy — sometimes abbreviated DM — is usually diagnosed in adults. It affects males and females equally. There are two types of myotonic dystrophy, known as DM1 and DM2. The type you develop depends on your genetic mutation.

Congenital muscular dystrophy (CMD) is a type of muscular dystrophy that usually develops in infants right after birth through age two. There are many subtypes of CMD — depending on the genetic mutation and affected muscle groups. Most infants and children with this disease have joint problems and progressive muscle weakness. Many don’t meet developmental milestones like sitting up, crawling, and walking at the typical ages.

Here are some additional types of muscular dystrophy:

• Limb-girdle muscular dystrophy — This type specifically affects the muscles in the shoulders and hips. There are more than 20 types of LGMD, which cause different symptoms.
• Facioscapulohumeral muscular dystrophy — This disease progresses slowly over time and weakens the muscles in the face, shoulders, and upper arms. Most people notice FSHD symptoms in their teenage years but can develop them as late as 40.
• Distal muscular dystrophy — There are many types of DD, and they can affect both males and females, per the National Institute of Neurological Disorders and Stroke. The muscles farthest away from your body are affected, such as the lower legs, feet, lower arms, and hands.
• Emery-Dreifuss muscular dystrophy — This type of muscular dystrophy causes muscle weakness in the upper arms, shoulders, heart, and lower legs. Children with EDMD usually develop symptoms by age 10. The disease progresses slowly over time.
• Oculopharyngeal muscular dystrophy — This rarer type of muscular dystrophy typically affects adults ages 40 to 50 and impacts the muscles that control the eye and throat muscles. OPMD affects the face first but can also lead to muscle weakness in the hips, legs, and shoulders.

3. Muscular Dystrophy Symptoms Depend on the Type and Severity

Each type of muscular dystrophy has unique symptoms — but they all cause muscle weakness and atrophy, which means the muscles shrink and lose strength over time. The specific muscles affected depend on the type. For example, DMD weakens the leg muscles, while FSHD affects the shoulders, upper arms, and face.

Muscle weakness makes it harder to get around and complete everyday tasks. People with muscular dystrophy may have problems:

• Walking and running or have an abnormal waddling gait (style of walking), leading to frequent falls
• Jumping
• Walking up and down stairs
• Lifting their arms above their heads

Other common signs and symptoms of muscular dystrophy include:

• Cardiomyopathy — Heart problems and breathing problems
• Joint stiffening or contractures — Tightening of your tendons, muscles, and skin
• Scoliosis — An abnormal side-to-side curve in the spine
• Dysphagia — Trouble swallowing due to muscle weakness

4. Doctors Run Several Tests To Diagnose Muscular Dystrophy

If you or your child is experiencing muscular dystrophy symptoms, it’s important to talk to a doctor. They’ll run a series of tests to make a diagnosis.

Doctors usually start with a physical exam to check your overall health. They’ll look at how you walk, and check your coordination and reflexes. Blood tests can also check for creatine kinase (CK). This enzyme (protein) is higher in people with muscular dystrophy. High levels of CK mean you have muscle damage.

Electromyography (EMG) is a test that measures how well your muscles use electricity to send signals and move. Your doctor may also recommend a muscle biopsy. They’ll take a small piece of muscle tissue to look at closely under a microscope. This test helps tell the difference between other muscle diseases.

Because muscular dystrophy is genetic, you may also have genetic testing. A blood sample is sent to a lab to look for any gene mutations. This test helps officially diagnose muscular dystrophy. It can also guide which treatment options may work best for you.

5. Muscular Dystrophy Treatments Include Medications and Supportive Therapies

In the last decade, doctors and researchers have discovered new ways to treat muscular dystrophy. Your treatment options depend on what type of muscular dystrophy you have. It’s important to work closely with your doctor to find the best option to improve your quality of life.

Examples of muscular dystrophy treatments include:

• Gene therapy for DMD to fix faulty dystrophin genes and make healthy proteins
• Corticosteroids (steroids), like deflazacort, to treat inflammation from muscle damage
• Nonsteroidal drugs to control inflammation without the unwanted side effects of steroids
• Physical therapy and occupational therapy for exercises and assistance with daily living tasks
• Supportive therapy and assistive devices like braces, walkers, and wheelchairs
• Medications and pacemakers to treat heart problems
• Cough assistive devices and ventilation to provide breathing support
• Surgery to treat contractures or scoliosis

6. People With Muscular Dystrophy Are at Risk of Certain Health Conditions

Sometimes, people with one disease are more likely to develop other related diseases. When you have two health conditions at the same time, they’re known as comorbidities. Researchers have found that people with muscular dystrophy are more likely to have:

• Learning disabilities
• Attention-deficit/hyperactivity disorder (ADHD)
• Obsessive-compulsive disorder (OCD)
• Anxiety and depression
• Autism spectrum disorder
• Obesity
• Epilepsy or seizures
• Kidney stones

Studies show that genetic factors play a role in comorbidities. For example, the muscle protein dystrophin is also found in the brain. Researchers haven’t quite found the connection between dystrophin and brain function. However, they think it affects thinking and information processing.

Talk to Your Doctor

If you have questions about muscular dystrophy or are worried about symptoms, talk to your doctor or pediatrician. They can explain treatment options and help you manage the condition. Learning more and working with your health care team can make it easier to handle the challenges of muscular dystrophy and improve your daily life.

Find Your Team

On myMDteam, the site for people with muscular dystrophy and their loved ones, members come together to gain a new understanding of muscular dystrophy and share their stories with others who understand life with the condition.

Have you or a loved one been diagnosed with muscular dystrophy? Do you have questions for others? Share your experiences in the comments below or by posting to your Activities page.