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Question #45842
The Question
A research team proposes using biotechnology to cure a patient with Klinefelter's syndrome (44 + XXY). Which of the following best explains why standard somatic gene therapy will fail, and identifies the primary cytological risk of attempting germline intervention at the zygotic stage to correct this condition?
Options
- A.
Somatic therapy targets localized gene sequences rather than whole-chromosome segregation machinery; germline intervention during cleavage risks disrupting the mitotic spindle, leading to lethal polyploidy.
- B.
Somatic therapy vectors cannot accommodate the large size of an entire X chromosome; germline intervention risks inducing frameshift mutations in the SRY gene.
- C.
Somatic therapy is restricted to autosomal recessive disorders; germline intervention during the zygotic stage will inevitably lead to X-chromosome inactivation in all blastomeres.
- D.
Somatic therapy cannot penetrate the germinal epithelium to correct the gametes; germline intervention risks triggering meiotic non-disjunction during embryonic cleavage.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Aneuploidy_vs_Polyploidy|Gene_Therapy_Germline_vs_Somatic|Human_Reproduction
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate 'Gene Therapy' (sequence-level modification) with the theoretical correction of 'Chromosomal Disorders' (aneuploidy).
The question tests the limitation of current biotech tools in managing chromosomal number versus sequence modification.
Furthermore, Option D serves as a high-yield 'Location/Process Trap' by mixing up the type of cell division (meiosis vs. mitosis) that occurs during embryonic cleavage.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Principles of Inheritance and Variation - Class 12 |
| Concept | Aneuploidy vs Polyploidy |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |