What is (are) Bethlem myopathy ?
Bethlem myopathy is an inherited movement disorder characterized by progressive muscle weakness and joint stiffness (contractures) in the fingers, wrists, elbows, and ankles. Due to a progressive course, up to two-thirds of people with this condition require a walker or wheelchair after the age of 50. Bethlem myopathy is caused by mutations in the COL6A1, COL6A2, and COL6A3 genes. Most cases are inherited in an autosomal dominant pattern and occur as the result of a new mutation. In rare cases, the disease follows an autosomal recessive pattern of inheritance. Treatment depends upon individual symptoms, but routinely involves physical therapy. Surgery or other measures may be undertaken as needed.