Question

The genetic defect, adenosine deaminase (ADA) deficiency, may be cured permanently by

• A. Periodic infusion of genetically engineered lymphocytes having functional ADA cDNA
• B. Administering adenosine deaminase activators
• C. Introducing bone marrow cells producing ADA into cells at early embryonic stages
• D. Enzyme replacement therapy

Answer 1

The correct option is C Introducing bone marrow cells producing ADA into cells at early embryonic stages

Severe combined immunodeficiency (SCID) is a life-threatening syndrome of recurrent infections, diarrhea, dermatitis, and failure to thrive that is caused by deficiency of the enzyme adenosine deaminase (ADA).

ADA-SCID patients can be cured by HLA-matched sibling donor bone marrow transplantation.

Alternative transplantation strategies as well as enzyme replacement are being tested in those patients who do not have a suitable matched sibling donor. Replacement therapy with PEG-ADA has resulted in improvement in growth, a variable increase in the number of peripheral blood lymphocytes, and a decrease in the incidence of severe infections.