Ataxia Telaniectasia

Ataxia-telangiectasia (AT)) is a basic immunodeficiency condition that is witnessed in 1 in 40,000 to 1 in 300,000 births.

Telangiectasias are tiny, red 'spider' arteries. These are generally seen on the surface of the cheeks and ears or in the outer regions of the eyes of the patients with AT. The AT patient feels difficulty in walking. At an early age, the kids’ walking becomes tottering, at teens, handicapped, and at the adult age of early 20s, the situation worsens and may become fatal.

Signs and Symptoms

AT is characterized by:

  • Chromosomal instability
  • Excessive sensitivity to ionising radiation
  • Increased conditions of malignancies (primarily lymphoid).
  • Increased alpha-fetoprotein levels
  • In some events the victim develops enlarged bowels, and loses appetite.
  • AT patients are significantly predisposed to cancer, specifically lymphomas and leukemia.
  • Sensitivity to ionizing radiation, premature aging, and hypogonadism is often witnessed.
  • Other characteristics of the disease are premature graying of hair, trouble in swallowing, slight diabetes mellitus, and late sexual and physical development.


Diagnosis is generally done by examination of both oculo-cutaneous telangiectasia and ataxia. It is then followed by laboratory tests to detect low levels of IgA, IgG2, IgG4, and IgE. Patient may also display a low lymphocyte level and other abnormalities pertaining to immunology. The next step would be cytogenetic and molecular examination to specify the diagnosis. MRI and CT scans may display signs of cerebellar atrophy.

Molecular Diagnosis

Molecular diagnosis of AT can be achieved by testing all 66 exon of the gene in case of any family history. Protein activity testing is also done. However AT testing is basically carried out cytogenetically as particular breakpoints and cytogenetic uncertainty are basic characteristic features of the ailment. In some patients this ailment reaches their immunoglobulin genes which can stretch during mitosis leading to prolymphocyte leukemia.

Antenatal diagnosis               

Antenatal diagnosis can be carried out by leveraging linkage and microsatellite markers. Nevertheless, direct gene analysis is more often conducted.


So far there seems to be three forms of AT:

  1. Actual AT where patients displaying all/most of the diagnostic symptoms.
  2. Attenuated AT in which sufferers do not manifests all of the diagnostic symptoms.
  3. Carrier AT where patients with a single ATM mutation are at higher risk to cancer.

Clinical Course

Sufferers are generally restricted to wheelchair at the age of 10 or 11. Telangiectasias are not generally witnessed in the early stages of the ailment and start to surface after a few years i.e. between 3-6 years of age, in the ears, cheeks and corners of the eyes. Patients are also at a 10% higher risk of developing cancer, usually lymphomas and sometimes breast cancer. Due to sufferers’ over sensitivity to ionising radiation, radiotherapy, and chemotherapy, it should be used with ample caution. People with the disease generally have common intelligence. Mental retardation is generally not found in people with A-T.

Prognosis of AT

The prognosis for AT sufferers is not good. Those with the disease generally die in their teens or early 20s, albeit some individuals have been witnessed to live to over 40. Some research papers claims a risk of lifetime for individual with both missense and null mutations of 10-38%, which is again cent percent enhancement from population risk.

Sufferers of any kind of ATM have a 5-8 folds greater risk of cancer and generally die 7-8 years prior to the normal age, generally from heart diseases.

Peoples with a single ATM mutation are at a greater risk to gastric, lung and lymphoid cancer, along with breast cancer. S707P is generally considered to be specifically normal in breast cancer sufferers and F1463S is usually considered to be linked with Hodgkin’s lymphoma. The study says that the majority of AT patients die from pulmonary infections (46%), with 21% dying from malignancies and 28% from pulmonary and malignancies infection.


Physical and occupational treatment may enable maintaining flexibility. Speech therapy may also be required. Gamma-globulin injections may also be advised to helps supplement a deteriorating immune system. High-dose vitamin schedules may also be suggested. Antibiotics are given to treat infections. Some physicians may recommend low doses of chemotherapy to cut down the risk of cancer but this is seldom and controversial also. It is also witnessed that heterozygote family members are often examined for cancers. Recently desferrioxamine was considered to consolidate the stability of AT cells and may appear to be an effective treatment for the disorder.

Genetic Counseling

All people with AT must undergo genetic counseling with their family members. This is especially necessary due to the catapulting risk of cancers that heterozygotes have. There is also a potential risk to any other children born to the couples of the affected child.