What is ARCUS?

ARCUS is a next-generation genome editing platform derived from a natural genome editing enzyme called a homing endonuclease.

Homing endonucleases

Homing endonucleases are nature’s genome editing system. They are site-specific DNA-cutting enzymes encoded in the genomes of many eukaryotic species. Homing endonucleases have the unusual ability to precisely recognize long DNA sequences (12-40 base pairs) that are typically rare enough to occur only once in a complex genome. These non-destructive enzymes trigger gene conversion events that modify the genome in a very precise way, most frequently by the insertion of a new DNA sequence. The ability to target a single DNA break in a complex genome and to achieve gene modification without random off-targeting makes homing endonucleases the ideal starting material for a therapeutic-grade genome editing technology.


The backbone of the ARCUS technology is the ARC nuclease – a fully synthetic enzyme similar to a homing endonuclease but significantly improved to be the starting point for the first therapeutic-grade genome editing platform. The ARC nuclease is small, has unparalleled specificity, and can be customized to recognize a DNA sequence within any target gene. ARC nucleases are created using a set of proprietary in silico and lab-based techniques to ensure maximum gene editing efficiency with minimum off-target activity. Importantly, ARC nucleases can be optimized to control potency and specificity based on the analysis of cutting activity in a relevant model organism.

What makes ARCUS unique in the world of genome editing?


Precision BioSciences owns ARCUS. Only a Precisioneer can make an ARCUS reagent.


ARCUS isn’t limited to deletions. ARCUS can be used to insert, delete or edit DNA.


ARCUS doesn’t miss its target. ARCUS doesn’t generate truly random DNA-breaks.


310 amino acids. 930 base pairs. ARCUS is compatible with essentially any delivery strategy.


Polypeptide. ARCUS is a single protein expressed from a single gene. There’s no need to deliver multiple parts.


Matched 4 base pair 3′ overhangs result in perfect, predictable removal of DNA.