Biology · PYQ NEET UG 2022

In gene therapy of Adenosine Deaminase (ADA) deficiency, the patient requires periodic infusion of genetically engineered lymphocytes because:

Lymphocytes from patient’s blood are grown in culture, outside the body.
Genetically engineered lymphocytes are not immortal cells.
Retroviral vector is introduced into these lymphocytes.
Gene isolated from marrow cells producing ADA is introduced into cells at embryonic stages.

Correct answer · Option 2

Genetically engineered lymphocytes are not immortal cells.

Genetically engineered lymphocytes used in ADA deficiency therapy are not immortal, hence patients require periodic infusions.