In gene therapy of Adenosine Deaminase (ADA) deficiency, the patient requires periodic infusion of genetically engineered lymphocytes because : [NEET-2022]

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

The NCERT line that answers it

Verbatim line

However, as these cells are not immortal, the patient requires periodic infusion of such genetically engineered lymphocytes.

Chapter: Biotechnology and its Applications
Section: 10.2.2 Gene Therapy
Page: 5
Words matched: 17 of 17

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span directly states 'as these cells are not immortal, the patient requires periodic infusion of such genetically engineered lymphocytes,' which is the exact biological fact that makes option D correct and distinguishes it from the other options.

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