A-T is inherited as an autosomal recessive disorder. (See chapter titled "Inheritance.") The ATM gene is found on the long arm of chromosome 11. This gene controls the production of the ATM protein, an essential enzyme involved in cellular responses to DNA damage and other forms of stress in every cell of the body. For example, if there is a break in the double strand structure of the DNA, ATM signals the cell to stop growing and dividing (cell cycle arrest), and ATM signals the DNA repair machinery of the cell to start working. The identification of the gene responsible for A-T has made carrier detection and prenatal diagnosis possible. Unfortunately, the sequencing test required to identify the mutation in the ATM gene is expensive and available in only a few laboratories.

1. General Treatment of Ataxia-Telangiectasia
There is no cure for any of the problems associated with A-T. Treatment is supportive but should be proactive. There are many parts of this disease, and a team approach, including the patient and family, primary care provider, immunologist, pulmonologist and neurologist is essential. A nutritionist as well as physical, occupational and speech therapists, will have important contributions to make for specific problems that patients encounter. An example of the utility of the team approach is to monitor for and manage swallowing problems. Dysphagia and tremor can make meals last a long time and be very fatiguing, can interfere with nutritional intake, and can lead to aspiration. Once recognized, early placement of a gastrostomy tube (G-tube, a tube that goes through the skin of the abdomen directly into the stomach) can provide supplemental nutrition that allows growth, improves stamina and decreases the risk of lung damage from aspiration.

All suspected infections should be properly evaluated and treated. Infection prevention efforts are important. This includes hand washing and making sure that those people with whom the patient comes in contact do not have acute respiratory tract infections. All household members should receive an influenza vaccination every fall. Patients with A-T who do not need immunoglobulin should receive all standard immunizations, as well as yearly influenza vaccine and a pneumococcal (pneumonia) vaccine every five to ten years.

Respiratory problems can be serious for patients with A-T. Often they have problems taking deep breaths and effectively coughing to clear mucus from their airways. They may benefit from daily chest physiotherapy and/or the use of a therapy vest. A regular program of respiratory care should be established before serious, irreversible lung problems develop. If chronic lung disease develops, patients may benefit from antibiotic prophylaxis, inhaled corticosteroids to decrease airway inflammation, and/or supplemental oxygen therapy. Patients who are having problems with aspiration (food and liquids going down the trachea into the lungs) may improve when thin liquids are eliminated from the diet. On occasion, it is safest for most food and liquid to be delivered directly into the stomach with a G-tube instead of being swallowed.

Diagnostic x-rays should be limited as A-T is a chromosomal breakage disorder, and there is the theoretical risk that x-rays could cause chromosomal damage. In general, x-rays should be performed only if the results will influence treatment and management, and the information cannot be obtained in any other manner.

Children with A-T should be able to attend school, but most of them will eventually require full time aides to assist with activities of daily living while at school. Academic difficulties occur because progressively impaired eye movements make reading difficult and because the delay in initiation of speech and impaired ability to write or use a computer limit the ability of patients with A-T to demonstrate what they have learned. Cognitive function and hearing is not impaired. It is often helpful to introduce books-on-tape at an early age to foster the development of listening skills, which will become increasingly important as visual problems progress. Computers can also be particularly helpful as they can be adapted to the particular needs of people who have problems with eye and hand coordination. Counseling for the patient and the family is almost always helpful.

2. Specific Therapy for Ataxia-Telangiectasia
There is neither a cure for A-T nor is there a specific therapy for the neurological problems associated with the disease. Nobody has yet shown in a convincing way that physical therapy or specific nutritional supplements (as opposed to general good nutrition) have helped, though there are many proponents of these approaches.

Management of immunodeficiency and general nutrition, prevention of pneumonia, and providing some exercise will improve the quality and length of life. Neither bone marrow transplantation nor injection of neural stem cells into the brain is considered safe at this time.