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How did bacteria inspire the development of CRISPR gene-editing technology?

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A step-by-step diagram shows donor DNA and vector DNA cut with restriction enzymes to create overhangs, mixed and sealed with ligase to form recombinant DNA, which is introduced into bacterial cells. The recombinant DNA replicates as the cells divide, producing clones. — biotechnology Steps involved in the engineering of a recombinant DNA molecule.

CRISPR gene-editing technology was inspired by the natural adaptive immune systems found in bacteria and archaea.12

In nature, these organisms use the CRISPR region of their genomes as a form of genetic memory to defend against invading pathogens, such as viruses. When a bacterium survives a viral attack, it incorporates a fragment of the viral DNA into its own genome as a "spacer" element.324

Upon a repeat infection, the bacterium transcribes these stored sequences into guide RNA. This RNA directs a nuclease—most notably the Cas9 enzyme—to the matching viral genetic material, where it catalyzes a double-stranded break to destroy the invader.342

Scientists, including Jennifer Doudna and Emmanuelle Charpentier, realized that this mechanism could be repurposed for gene editing. By modifying the guide RNA to target specific DNA sequences, researchers can direct the Cas9 enzyme to create precise cuts in the genomes of other organisms, allowing for the removal or insertion of genetic material with high efficiency and specificity.123