Yet others, called base editors, change one letter of the DNA code to another. So why do we call it CRISPR? Cas proteins are used by bacteria to destroy viral DNA. They add bits of viral DNA to ...

Scientists have categorized different types of CRISPR systems into two classes based on how their Cas nucleases function. In class 1 (types I, III, and IV), different Cas proteins form a complex ...

CRISPR-Cas systems are prokaryotic immune systems that confer resistance to foreign genetic elements such as plasmids and phages. CRISPR-Cas systems have been exploited for targeted genome editing.

CRISPR-Cas9 genome editing exploits the CRISPR-Cas system to modify a genome in a targeted manner. Guided by RNA, the Cas9 endonuclease breaks DNA at a target sequence. Imprecise repair of the ...

Cas9, the first Cas protein repurposed for cutting DNA, introduces double-strand breaks that recruit DNA repair machinery. Despite its successes, the CRISPR-Cas9 system has several limitations, ...