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How do CRISPR-Cas13 systems differ from CRISPR-Cas9 systems?

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CRISPR-Cas9; gene editing — gene editing The CRISPR-Cas9 gene-editing complex from the bacterium *Streptococcus pyogenes*.

The primary difference between CRISPR-Cas9 and CRISPR-Cas13 systems lies in their target molecules. While the CRISPR-Cas9 system is widely recognized for its ability to target and cleave double-stranded DNA, CRISPR-Cas13 systems are designed to target RNA.3

The CRISPR-Cas9 system, derived from the adaptive immune systems of bacteria, utilizes a guide RNA to direct the Cas9 nuclease to a specific DNA sequence, where it introduces a double-stranded break. This mechanism has become a cornerstone of gene editing due to its precision in modifying genomic sequences.123

In contrast, CRISPR-Cas13 is part of a broader expansion of CRISPR-based tools developed to increase the versatility of genetic engineering. By targeting RNA rather than DNA, Cas13 systems offer researchers different functional capabilities, such as the ability to modulate gene expression or manipulate RNA transcripts without permanently altering the underlying genome.3