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Question #45141
The Question
Biologists draw a conceptual parallel between ex vivo gene therapy for Adenosine Deaminase (ADA) deficiency and ex situ conservation (e.g., captive breeding). Both are 'extracorporeal rescue' strategies involving the removal, modification or amplification, and reintroduction of a biological unit to counter a systemic deficit. Which of the following statements regarding these strategies is INCORRECT?
Options
- A.
In ADA gene therapy, a functional ADA cDNA is introduced into the patient's cultured lymphocytes using a disarmed retroviral vector before reintroduction.
- B.
Both strategies face long-term sustainability challenges; captive populations risk genetic bottlenecks, while ADA patients require periodic infusions because the engineered lymphocytes are not immortal.
- C.
A permanent cure for ADA deficiency is achieved if the functional gene, isolated from bone marrow cells, is introduced into the patient's cultured lymphocytes during early childhood.
- D.
Advanced ex situ conservation employs cryopreservation of gametes and in vitro fertilization, conceptually mirroring the ex vivo cellular manipulation utilized in gene therapy.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
ADA_Gene|Ex-situ_Conservation|Gene_Pool_Stability
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The trap exploits the distinction between temporary management and permanent cure in gene therapy.
Students often memorize 'bone marrow' and 'gene therapy' as a permanent cure but overlook the critical NCERT caveat: the intervention must occur at the 'early embryonic stages,' not during 'early childhood,' and targets embryonic cells, not differentiated 'lymphocytes.'
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology and Its Applications - Class 12 |
| Concept | ADA Deficiency Genetic Correction |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |