What It Is
Ataxia-telangiectasia (A-T) is a rare, progressive neurodegenerative genetic disease that becomes evident in early childhood, usually in the first few years of life. A-T causes degeneration in the part of the brain that controls motor movements and speech. Some children will develop normally the first 3-5 years before regressing and exhibiting difficulty in walking or standing without support.
A-T is inherited as an autosomal recessive trait with both parents contributing a gene for A-T to the affected child. The gene is on chromosome 11. It is called ATM (which stands for ataxia-telangiectasia mutated). ATM encodes a protein that is predominantly confined to the nucleus of cells and that remains constant throughout all stages of the cell cycle. A disorder called the Nijmegen breakage syndrome (NBS1) is similar to A-T. The ATM and NBS1 genes appear to be in a common signaling pathway that choreographs the cell's responses to genomic damage.
The hallmarks of A-T are Cerebellar Ataxia, which results in lack of balance and coordination and difficulties with speech; Ocular Telangiectasias, or tiny red "spider" veins, which appear in the whites of the eyes due to widening of small blood vessels in the conjuntiva, or on the surface of the ears and cheeks; Immune Defects; and a predisposition (about 1/3) to leukemia and lymphoma.
People with A-T are also extremely sensitive to radiation exposure. Most people with A-T have a defective immune system, making them susceptible to recurrent sinus and respiratory infections. Other features of the disease may include diabetes mellitus, premature graying of the hair, difficulty swallowing (which causes choking and drooling), and slowed growth.
Children with A-T usually have and maintain normal or above normal intelligence.
Treatments & Therapies
There is no cure for A-T and, currently, there is no known therapy to slow the progression of the disease. Treatment is symptomatic and supportive. Physical and occupational therapy may help maintain flexibility. Speech therapy may also be useful. Intravenous immune globulin (IVIG) injections may help supplement the defective immune system. High-dose vitamin regimes have been tried. The longterm prognosis for people with A-T is poor. While the average lifespan has been improving in recent years, it varies with the severity of the underlying mutations, ATM (ataxia-telangiectasia mutated) protein levels, and residual ATM kinase activity and those with the disease usually die in their teens or early 20s.
- The description of this disease is provided courtesy of the A-T Children’s Project, the NIH, and other sources.
- The information provided on this web site should NOT be used as a substitute for seeking professional medical diagnosis, treatment or care. You should not rely on any information in these pages to replace consultations with qualified health professionals.