[Campbell Biology P.483] The gene therapy trials for SCID in France, though initially succes... | Practice Question

The gene therapy trials for SCID in France, though initially successful, faced a serious complication. What was this complication, and what is a more modern approach mentioned to potentially avoid such issues?

  • A: Patients developed severe immune reactions, and a new approach involves using immunosuppressants.
  • B: The inserted gene expression was uncontrollable, and gene editing offers precise control.
  • C: The retroviral vector's insertion near a gene triggering blood cell proliferation led to leukemia, and gene editing using the CRISPR-Cas9 system is a more direct approach.
  • D: The gene therapy caused rejection of the bone marrow cells, and future therapies use stem cells from other sources.

Explanation

The text states that the retroviral vector's insertion near a gene triggering blood cell proliferation led to leukemia in some SCID patients. It then introduces 'gene editing, especially using the CRISPR-Cas9 system' as a 'more direct approach that avoids the complications of using a viral vector in gene therapy.'