Ataxia telangiectasia

Definition

Ataxia telangiectasia is a rare genetic disorder that affects the nervous and immune systems, leading to symptoms such as progressive ataxia, telangiectasia (small dilated blood vessels), and increased susceptibility to infections and cancer. This disorder is primarily linked to mutations in the ATM gene, which plays a crucial role in DNA repair mechanisms, particularly in response to DNA double-strand breaks.

5 Must Know Facts For Your Next Test

1. Ataxia telangiectasia is inherited in an autosomal recessive pattern, meaning both parents must carry a copy of the mutated ATM gene for a child to be affected.
2. Individuals with ataxia telangiectasia often experience difficulty with coordination and balance due to progressive neurological degeneration.
3. The disorder can lead to an increased risk of developing various cancers, particularly lymphomas and leukemias, due to impaired DNA repair processes.
4. Telangiectasia can become noticeable in childhood as small red spots on the skin, particularly on the face and eyes, which is one of the hallmark signs of the condition.
5. Patients with ataxia telangiectasia may also experience immunodeficiency, leading to recurrent infections and complications related to poor immune response.

Review Questions

• How does the mutation in the ATM gene relate to the symptoms observed in individuals with ataxia telangiectasia?
  • The ATM gene is crucial for the detection and repair of DNA double-strand breaks. When this gene is mutated, the body's ability to respond to DNA damage is compromised, leading to genomic instability. This instability can manifest as neurological symptoms like ataxia due to degeneration of motor control pathways and an increased risk of cancers due to inadequate repair mechanisms.
• What role does immunodeficiency play in the overall health challenges faced by individuals with ataxia telangiectasia?
  • Immunodeficiency in ataxia telangiectasia significantly impacts overall health by making individuals more susceptible to infections. This occurs because the immune system cannot effectively respond to pathogens due to defects in immune cell function. Consequently, patients may face recurrent infections and additional complications, further complicating their management and care.
• Evaluate the implications of DNA repair deficiencies in ataxia telangiectasia on cancer susceptibility and treatment outcomes.
  • The deficiencies in DNA repair mechanisms associated with ataxia telangiectasia lead to an increased risk of developing cancers like lymphomas and leukemias due to accumulated genetic mutations. This raises significant concerns for treatment outcomes since traditional therapies such as radiation can exacerbate DNA damage in these patients. Understanding these implications helps guide clinicians in tailoring safer treatment strategies while monitoring for potential malignancies early in affected individuals.

Related terms

ATM Gene: A gene that encodes a protein essential for the detection and repair of DNA double-strand breaks, crucial for maintaining genomic stability.

DNA Double-Strand Breaks: A type of DNA damage that occurs when both strands of the DNA helix are severed, which can lead to genomic instability if not repaired properly.

Immunodeficiency:

A condition where the immune system's ability to fight infectious disease is compromised or entirely absent, often seen in individuals with ataxia telangiectasia.