Adenosine deaminase deficiency

Definition

Adenosine deaminase deficiency (ADA deficiency) is a genetic disorder that affects the immune system by impairing the breakdown of adenosine and deoxyadenosine. This leads to severe combined immunodeficiency (SCID), making individuals highly susceptible to infections.

5 Must Know Facts For Your Next Test

1. ADA deficiency is caused by mutations in the ADA gene on chromosome 20.
2. It results in the accumulation of toxic metabolites, which are harmful to lymphocytes.
3. Gene therapy has been used to treat ADA deficiency by inserting a functional copy of the ADA gene into hematopoietic stem cells.
4. The first successful gene therapy trial for ADA deficiency was conducted in the early 1990s.
5. Patients with untreated ADA deficiency typically exhibit severe infections within the first few months of life.

Review Questions

• What enzyme is deficient in individuals with ADA deficiency?
• How does ADA deficiency lead to severe combined immunodeficiency (SCID)?
• What is one method used in gene therapy to treat ADA deficiency?

Related terms

Severe Combined Immunodeficiency (SCID):

A group of rare disorders caused by mutations affecting immune cell development, leading to profound immunodeficiency.

Gene Therapy:

A medical technique that involves modifying or manipulating genes within an individual's cells to treat or prevent disease.

Hematopoietic Stem Cells:

Stem cells found in bone marrow that give rise to all blood cells, including immune cells.