Ataxia–telangiectasia

Ataxia-telangiectasia (A-T) is a rare, neurodegenerative, autosomal recessive disease causing severe disability. A-T is characterized by progressive cerebellar ataxia, telangiectasia, immune defects, and a high rate of cancer.

Etymology

The term "ataxia" comes from the Greek word "ataxis" which means "without order or incoordination". The term "telangiectasia" is derived from the Greek words "telos" meaning "end", "angeion" meaning "vessel", and "ektasis" meaning "dilation". This refers to the dilation of end vessels found in patients with the condition.

Symptoms and Signs

The symptoms and signs of A-T are diverse and include severe progressive cerebellar ataxia, oculomotor apraxia, immune defects, recurrent sinopulmonary infections, and an increased risk of malignancies, particularly of lymphoid origin.

Causes

A-T is caused by a mutation in the ATM gene, which is involved in DNA repair. This mutation leads to a decrease in the production of the ATM protein, which is crucial for the normal function of several other proteins involved in the cell cycle control and DNA repair.

Diagnosis

Diagnosis of A-T is based on clinical features, laboratory findings of IgA deficiency and increased alpha-fetoprotein, and molecular genetic testing of the ATM gene.

Treatment

There is currently no cure for A-T. Treatment is supportive and includes physical and occupational therapy, gamma-globulin injections to boost the immune system, and high-dose vitamins.

Prognosis

The prognosis for individuals with A-T is poor. Most people with A-T become wheelchair-bound by their teens and do not survive past their early twenties.

See Also

• Neurodegenerative disorders
• Autosomal recessive disorders
• DNA repair

• Ocular telangiectasia in a person with A-T
  Ocular telangiectasia in a person with A-T
• 
  Autosomal recessive inheritance pattern
• Alu element ATM insertion
  Alu element ATM insertion
• Characteristics of the ATM protein
  Characteristics of the ATM protein
• ATM and the immune system
  ATM and the immune system
• Comparison of rare genetic disorders that can be confused with A-T
  Comparison of rare genetic disorders that can be confused with A-T
• Mechanism of action of antisense oligonucleotides (ASOs)
  Mechanism of action of antisense oligonucleotides (ASOs)