Ques. 1AIPMT 2009
The genetic defect – adenosine deaminase (ADA) deficiency may be cured permanently by
- Introducing bone marrow cells producing ADA into cells at early embryonic stages
- Periodic infusion of genetically engineered lymphocytes having functional ADA cDNA
- Administering adenosine deaminase activators
- Enzyme replacement therapy
Answer
(1) Introducing bone marrow cells producing ADA into cells at early embryonic stages
Solution
As per NCERT, ADA deficiency can be treated by bone marrow transplantation, enzyme replacement therapy or periodic infusion of genetically engineered lymphocytes — none of these is completely curative, as the lymphocytes are not immortal.
⇒ NCERT states: if the gene isolated from bone marrow cells producing ADA is introduced into cells at early embryonic stages, it could be a permanent cure.
Answer: (1)