X-linked distal spinal muscular atrophy type 3

X-linked distal spinal muscular atrophy type 3 is a rare condition that affects the nerves controlling the muscles in the hands and feet. It causes slowly progressive weakness and wasting (atrophy) in these muscles. In many cases, the deep tendon reflexes are normal, although there may be absent ankle reflexes. The condition is most often observed in males due to its X-linked pattern of inheritance. Some people with this condition may also experience mild weakness in the leg muscles closer to the body (proximal weakness) and may develop hand deformities. This disorder is a type of distal hereditary motor neuropathy and is linked to changes in the ATP7A gene. The genetic basis and specific pattern of muscle involvement help define the disease and guide further understanding of its progression.

People with this condition often show gradually worsening weakness and muscle loss in the hands and feet. Many have normal deep tendon reflexes, although some may lose the normal responses at the ankles. Minimal or no sensory loss is noted. In addition, there can be mild weakness in muscles closer to the trunk and hand deformities may occur, particularly in males.

This condition is caused by changes in the ATP7A gene. It is an X-linked disorder, which means that the mutation is located on the X chromosome. Because of this inheritance pattern, it primarily affects males. The mutation in the ATP7A gene interferes with normal nerve and muscle function, leading to the symptoms seen in this disorder.

Information about treatment is currently limited for this condition.

Information about prognosis is currently limited for this condition.

Information about current research and future directions is currently limited for this condition.