What is Myotonic muscular dystrophy

Myotonic muscular dystrophy (MMD) is a genetic disorder that affects the muscles and other systems in the body. It is the most common form of muscular dystrophy in adults, with two main types: type 1 (DM1) and type 2 (DM2).

DM1 is caused by a mutation in the DMPK gene, while DM2 is caused by a mutation in the CNBP gene. Both types result in the abnormal expansion of repeated DNA sequences, leading to the production of faulty proteins.

The hallmark symptom of MMD is myotonia, which is the prolonged contraction of muscles after use. This can cause muscle stiffness, weakness, and difficulty relaxing muscles. Other common symptoms include muscle wasting, cataracts, heart abnormalities, respiratory issues, and cognitive impairments.

MMD is a progressive condition, meaning symptoms worsen over time. The age of onset, severity, and progression can vary widely among individuals. It is inherited in an autosomal dominant pattern, meaning a person with MMD has a 50% chance of passing the condition to their children.

While there is currently no cure for MMD, treatment focuses on managing symptoms and improving quality of life. This may involve physical therapy, assistive devices, medications, and regular monitoring of associated health complications.