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BiologyGenetics12 minIntermediate

CRISPR-Cas9 Gene Editing

Visualize how guide RNA directs Cas9 to a DNA target so a precise cut can start a repair outcome.

Annotated teaching image of CRISPR-Cas9 binding and cutting target DNA.
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Cas9 protein

DNA-cutting protein guided to a matching target sequence.

CRISPR-Cas9 uses a guide RNA to bring Cas9 to a matching DNA sequence. After recognition, Cas9 cuts both strands, and the cell's repair systems determine the final editing outcome.

This technology is adapted from bacterial defense systems that recognize and cut genetic material.

Key Idea

CRISPR editing separates targeting from cutting: guide RNA provides sequence specificity, while Cas9 supplies the cutting machinery.