What is myotonic muscular dystrophy? - Muscular Dystrophy Queensland

Myotonic muscular dystrophy (MMD) and congenital myotonic dystrophy (CMD)

Myotonic muscular dystrophy (MMD), also known as Steinert’s disease, is the most common form of adult muscular dystrophy. In children, it is called congenital myotonic dystrophy.

It is a genetic condition that occurs when a section of the faulty gene (either DMPK or CNBP genes) is larger than it should be, affecting the messages sent to the muscle cell, ultimately leading to muscle weakness. This mutation is present from birth, however, may not cause symptoms until later in life.

A key attribute of DM is myotonia, difficulty relaxing a tightened muscle after use.

The disease is caused by abnormal expansions of repeated areas of genes which may increase with each generation leading to earlier onset, and increased severity of symptoms in succeeding generations, particularly when passed on from a mother.

MMD affects the muscles supporting the skeletal system, hands, feet, heart, eyes, and respiratory muscles.

Types of Myotonic Dystrophy

  • Type 1 DM (DM1)
  • Congenital-onset DM1
  • Childhood or juvenile-onset DM1
  • Adult-onset (classic) DM1
  • Mild DM1
  • Type 2 DM (DM2)

Myotonic

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Medical Alert Cards

Medical Alert Cards


Muscular Dystrophy Queensland has created condition-specific alert cards for the most diagnosed muscle-wasting conditions.

These cards mean that people living with muscle wasting conditions and their families will have the security of knowing they can easily inform emergency health care professionals of the vital and specific issues that affect children and adults with these conditions.

Order our Medical Alert Card for Myotonic dystrophy type 1 and type 2 today

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By becoming a registered Community Member of Muscular Dystrophy Queensland you will be able to gain access to relevant supports.

At Muscular Dystrophy Queensland we don’t see you as just a client. You are a valued member of our community. We’re here to support you through every stage of life. We’d like to keep in touch with you, to understand your needs as they evolve and provide you with ongoing access to our range of services. And so, we ask you to register with us. 

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