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Ataxia-telangiectasia

An evidence-led atlas of ATM deficiency, progressive ataxia, immune and lung disease, cancer risk, radiation sensitivity, and multidisciplinary care.

ataxia telangiectasia · A-T · Louis-Bar syndrome

MONDO:0008840Public QA completeSource-bound · 4

Disease at a glance

Start with the essentials, then explore the patient and research views.

Public revision · 09c685020058

Disease class
A-T is a multisystem genetic disorder affecting the nervous and immune systems, lungs, and cancer risk.
Core mechanism
It is caused by biallelic pathogenic ATM variants and is inherited in an autosomal-recessive manner.
Genes or cause
Residual ATM function contributes to a spectrum from classic to milder variant disease.
Typical features
Classic A-T begins in childhood with progressive gait and coordination difficulty and later speech and eye-movement abnormalities.
Variability
Ocular and skin telangiectasias may be absent at onset and appear years later.
Diagnosis
Diagnosis integrates clinical findings, AFP and immune tests, ATM protein or function, and identification of biallelic pathogenic variants.
Management
AFP can be physiologically high before age two and is unreliable as a stand-alone marker then.
Treatment and research
Immune deficiency can cause recurrent infection, while swallowing and neurologic problems can increase aspiration and chronic lung-disease risk.
Reading evidence
Risk is increased for leukemia, lymphoma, and some solid tumors, warranting prompt assessment of new symptoms.
Key caution
Sensitivity to ionizing radiation and radiomimetic drugs requires avoiding unnecessary exposure and specialist planning of imaging and cancer therapy.

For patients and families

A structured guide for understanding the disease and preparing for clinical conversations.

At a glance

A-T is a multisystem genetic disorder affecting the nervous and immune systems, lungs, and cancer risk.

Classic A-T begins in childhood with progressive gait and coordination difficulty and later speech and eye-movement abnormalities.

How the disease works

It is caused by biallelic pathogenic ATM variants and is inherited in an autosomal-recessive manner.

Residual ATM function contributes to a spectrum from classic to milder variant disease.

Why experiences vary

Ocular and skin telangiectasias may be absent at onset and appear years later.

Diagnosis and management

Diagnosis integrates clinical findings, AFP and immune tests, ATM protein or function, and identification of biallelic pathogenic variants.

Treatment status

AFP can be physiologically high before age two and is unreliable as a stand-alone marker then.

Immune deficiency can cause recurrent infection, while swallowing and neurologic problems can increase aspiration and chronic lung-disease risk.

Reading clinical trials

Follow-up requires multidisciplinary neurology, immunology, respiratory, oncology, rehabilitation, and genetic counseling.

Topics for a clinical visit

Clinical discussion should cover phenotype, immune and lung status, cancer warning signs, radiation exposure, and implications of family testing.

Medical notice

This material is for disease education and is not a personal diagnosis or treatment instruction.

Evidence and sources

A trial registry status does not establish efficacy or regulatory approval.