Question

Absence of the enzyme adenosine deaminase in humans causes:

• A. Thalassemia
• B. Sickle cell anaemia
• C. SCID
• D. Mad cow disease

Hint:

ADA deficiency causes SCID, a severe immune disorder due to toxic metabolite buildup.

Answer 1

The Correct Option is C

Adenosine deaminase (ADA) is an enzyme involved in purine metabolism. Its absence leads to the accumulation of toxic metabolites that severely affect the immune system, causing Severe Combined Immunodeficiency (SCID), a genetic disorder characterized by a weakened immune response.

• SCID: Caused by ADA deficiency, leading to impaired immune function.
• Thalassemia and Sickle cell anaemia: Are blood disorders caused by mutations in hemoglobin genes, unrelated to ADA.
• Mad cow disease: Is a prion disease affecting the brain, unrelated to ADA enzyme.

Thus, the correct answer is (C) SCID.