Question

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

• A. Enzyme replacement therapy.
• B. Bone marrow transplantation.
• C. Introducing isolated gene from bone marrow cells producing ADA into the cells at early embryonic stages.
• D. Administering adenosine deaminase through injection.

Answer 1

The correct option is C Introducing isolated gene from bone marrow cells producing ADA into the cells at early embryonic stages.

The disorder ADA deficiency is caused due to deletion of the gene for adenosine deaminase. ADA deficiency can be cured by bone marrow transplantation or by enzyme replacement therapy, in which functional ADA is given to the patient by injection. But both these approaches are not completely curative as the patient requires periodic infusion of such genetically engineered lymphocytes or hormonal injections.

However, if the gene isolated from marrow cells producing ADA is introduced into cells at early embryonic stages, it could be a permanent cure.