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Ataxia-telangiectasia syndrome

Synonyms
AT, COMPLEMENTATION GROUP C; ATAXIA-TELANGIECTASIA, COMPLEMENTATION GROUP A; ATAXIA-TELANGIECTASIA, FRESNO VARIANT; Ataxia-telangiectasia; Ataxia-telangiectasia, complementation group D; Ataxia-telangiectasia, complementation group E; Cerebello-oculocutaneous telangiectasia; Immunodeficiency with ataxia telangiectasia; Louis-Bar syndrome
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Excerpted from the GeneReview: Ataxia-Telangiectasia
The phenotypic spectrum of ataxia-telangiectasia (A-T), a multisystem disorder, is a continuum ranging from classic A-T at the severe end and variant A-T at the milder end. Nonetheless, distinguishing between classic A-T and variant A-T on this spectrum helps understand differences in disease course, rate of progression, and life expectancy. Classic A-T is characterized by childhood onset of progressive neurologic manifestations (initially cerebellar ataxia, followed typically by extrapyramidal involvement and peripheral sensorimotor neuropathy), immunodeficiency (variably associated with abnormalities of humoral immunity, cellular immunity, or combined immune deficiency), pulmonary disease (resulting from recurrent infections, immune deficiency, aspiration, interstitial lung disease, and neurologic abnormalities), and increased risk of malignancy. Although it is generally accepted that intellectual disability is not common in A-T, disturbances in cerebellar as well as non-cerebellar brain areas and networks may result in cognitive deficits. Increased sensitivity to ionizing radiation (x-ray and gamma ray) can result in severe side effects from such treatments. Life expectancy is significantly reduced due to cancer, pulmonary disease, and infections. Variant A-T has a significantly milder disease course. While cerebellar ataxia can be absent, extrapyramidal movement disorders are common (typically dystonia and dystonic tremor) and most individuals have manifestations of axonal sensorimotor polyneuropathy. In contrast to classic A-T, immune function is generally normal, respiratory infections are not increased, and pulmonary disease is not a major feature. However, risk of developing malignancies is increased, particularly in premenopausal females who have an increased risk of developing breast cancer and hematologic malignancies.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Stefanie Veenhuis
Nienke van Os
Corry Weemaes
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Available tests

213 tests are in the database for this condition.

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Clinical tests (213 available)

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Cytogenetics Tests

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Genes See tests for all associated and related genes

  • Also known as: AT1, ATA, ATC, ATD, ATDC, ATE, TEL1, TELO1, ATM
    Summary: ATM serine/threonine kinase

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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