X-linked Charcot-Marie-Tooth disease

X-linked Charcot-Marie-Tooth disease (also known as CMTX) is a subtype of Charcot-Marie-Tooth disease, a group of inherited disorders that affect the peripheral nerves. CMTX is specifically caused by mutations in the GJB1 gene, which is located on the X chromosome.

Genetics

CMTX is an X-linked dominant condition, which means that both males and females can be affected, but males are typically more severely affected. The GJB1 gene provides instructions for making a protein called connexin 32, which forms channels that allow small molecules to pass between cells. Mutations in the GJB1 gene disrupt the function of these channels, leading to the symptoms of CMTX.

Symptoms

The symptoms of CMTX usually begin in childhood or early adulthood and can include muscle weakness and wasting, decreased sensation in the extremities, and difficulty with balance and coordination. Some people with CMTX may also have hearing loss or abnormalities in the structure of the eye.

Diagnosis

Diagnosis of CMTX is based on the presence of characteristic symptoms, a family history of the condition, and genetic testing to identify a mutation in the GJB1 gene. Other tests, such as nerve conduction studies and electromyography, may also be used to confirm the diagnosis.

Treatment

There is currently no cure for CMTX, and treatment is focused on managing symptoms. This can include physical therapy, occupational therapy, and the use of assistive devices such as braces or orthotics. Some people with CMTX may also benefit from medications to manage pain or other symptoms.

See also

• Charcot-Marie-Tooth disease
• Peripheral neuropathy
• X-linked dominant inheritance