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If you are looking at this site, you or one of your family members has likely recently received a diagnosis of myotonic dystrophy (DM). This news can be overwhelming, and it may take some time for you and your family to adjust. We hope this site will be able to help you navigate the path of myotonic dystrophy; our goal is to provide you with accurate information about DM and share the experiences of other remarkable people who have this disorder.

Note: Medical information available on this site is designed as general information only. Patients should consult with a physician or other qualified medical professionals for advice on medical treatment.

Myotonic dystrophy (DM) is a genetic disorder that affects many parts of the body. There are different types of DM, and some cause more serious problems than others. There is currently no cure for myotonic dystrophy, but there is a lot you can do to improve your quality of life, by taking part in your care and actively managing your symptoms. 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. Learn as much as you can about your condition so you can talk to your doctors and educate the people around you. Stay up to date on new developments so you can ensure that you get the best possible care.

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How DM Affects Your Body

Myotonic dystrophy is a very complicated condition. The symptoms and disease progression can vary widely. The effects can be quite different even among members of the same family, so it is difficult to predict just how the disorder will affect you and your family. One person may only have mild muscle pain or cataracts that develop in later years, while someone else with the condition may be born with serious breathing problems.

The most common effects of DM are muscle problems, including muscle weakness (myopathy), trouble relaxing a muscle (myotonia), and muscle wasting that gets worse over time (atrophy). However, it is misleading to think of DM as only a muscle disorder because it also affects many other body functions, including the heart, lungs, and gastrointestinal (GI) system. The disorder can also cause problems with cognitive function, personality, and vision. Not everyone with DM will have all or even most of the possible symptoms.

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Disease Mechanism

Myotonic dystrophy is one of the most complex disorders known. In addition to the incredible variability of clinical symptoms the disease also has unique mechanistic features:

  • True autosomal inheritance. The disease phenotype of patients who are homozygous for myotonic dystrophy is essentially the same as those who are heterozygous.
  • Variable penetrance. Considerable variability is seen between affected individuals, even within the same family. Somatic mosaicism is common, where the genetic defect can be significantly different in various tissues in a single individual and can change over time.
  • Anticipation. The disease symptoms tend to be more severe and occur earlier in successive generations.
  • Maternal transmission bias for the congenital form. In the most severe form of myotonic dystrophy (congenital myotonic dystrophy: DM1), transmission is nearly always maternal and does not appear to be related to the severity of the disease in the mother. The mutated gene is only very rarely inherited from the father in newborns with myotonic dystrophy.

A Short To Do List for Newly Diagnosed Families

Myotonic has a comprehensive array of resources available for newly-diagnosed families, available via the Resources link on this website. Below are links to some of our most commonly-requested resources:

  1. Order an Myotonic Toolkit
  2. Join the Myotonic Dystrophy Family Registry
  3. Download the Anesthesia Guidelines
  4. Find a doctor or other DM medical professional near you
  5. Request support from our professionally-staffed Warmline
  6. Sign up for emails from Myotonic
  7. Find a local support group near you
  8. Register for Research Studies and Clinical Trials
  9. Obtain Disability Benefits (for U.S. residents only)

Questions? Contact Myotonic for more information via email or phone (415-800-7777)

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