What is myotonic dystrophy? (DM)
Myotonic dystrophy (“DM”) is a genetic disorder that affects many parts of the body. Although there is currently no cure, there is a lot you and your healthcare team can do to improve your quality of life by learning about DM, participating in your care, and actively managing your symptoms.
Learning more about DM
New discoveries about the disorder and how it can be treated are coming to light almost every day, but for the most part myotonic dystrophy is not well understood by the general medical community. You’ll want to learn as much as you can about the condition so you can talk to your doctors and educate the people around you.
How DM affects people
Myotonic dystrophy affects everyone differently. Symptoms can begin at different ages and may change over time. Some people experience mild muscle stiffness, fatigue, or cataracts, while others may develop symptoms that affect breathing, the heart, or daily activities.
This wide range of experiences can make DM difficult to predict. Understanding that there is no single “typical” DM experience can help you and your healthcare team focus on what matters most for you and adjust care as your needs change.
Types of myotonic dystrophy
There are two main types of myotonic dystrophy: myotonic dystrophy type 1 (DM1) and myotonic dystrophy type 2 (DM2).
DM1 is further classified based on the age at which symptoms first appear. These include congenital myotonic dystrophy (CDM), juvenile-onset adult (JOA) DM1, and adult-onset DM1. Each form can affect the body differently and may involve different care and monitoring needs.
Why is it called “DM”?
Myotonic dystrophy is often shortened to “DM”. This abbreviation comes from the Latin name for the condition, dystrophia myotonica, which is commonly used in medical and research settings.
You may also hear other names used by doctors and researchers:
- Myotonic Muscular Dystrophy (MMD)
- Steinert’s Disease
- Proximal Myotonic Myopathy (PROMM)
These names all refer to forms of myotonic dystrophy.
Understanding myotonic dystrophy further
Understanding Myotonic Dystrophy - The Basics
Published: November 20, 2024
How myotonic dystrophy type 1 (DM1) is inherited
Published: February 21, 2025
How myotonic dystrophy type 2 (DM2) is inherited
Published: September 24, 2025
