A researcher wishes to repress the transcription of a specific gene without cutting the DNA. They engineer a catalytically dead Cas9 (dCas9) that lacks endonuclease activity and fuse it to a transcriptional repressor domain. This modified CRISPR system is best described as:
- A CRISPR interference ✓
- B CRISPR activation
- C Base editing
- D Prime editing
Correct answer: A. CRISPR interference
Explanation
CRISPR interference (CRISPRi) uses catalytically dead Cas9 (dCas9) fused to a transcriptional repressor to block transcription without cutting DNA. CRISPRa uses an activator to enhance transcription. Base editors chemically alter single nucleotides without causing double-strand breaks.
Reference: Molecular Biology of the Cell, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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