RITDM™ gene editing technology
Safe gene editing by avoiding DNA breaks
Many gene editing technologies involve the creation of single stranded or double stranded DNA breaks. As a consequence of creating DNA breaks, cells typically activate a number of DNA repair processes, including Non-homologous End Joining, that can lead to mutagenic off-target effects.
At PeterBio we created a new technology that does not depend on the creation of DNA breaks.
Our RITDM™ (Recombination Induced Template-driven DNA Modification) technology is an innovative way of gene-editing that exploits cellular processes in which single stranded DNA is present. One such opportunity was developed based on carefully studying nature’s way of cell division. In normal cell division the DNA replication fork exposes short stretches of single stranded DNA to which complementary correction templates can bind. DNA mismatch repair can be used to generate daughter cells with the desired DNA change. A major benefit of our technology is that gene editing can occur without DNA breaks that activate Non-homologous End Joining, significantly reducing the risk of unintended changes in the genome.
In this version of the technology RITDM™ works by slowing down the replication fork in the vicinity of the DNA target site. This is needed to allow enough time for the correction template to find and bind to the single stranded target site. We achieve this by creating special fusion proteins that can sequence-specifically bind to the target site, thereby forming a temporary, local barrier for DNA replication. This triggers an extended exposure of single stranded DNA, allowing the complementary correction template to bind.
We are also developing variations of the RITDM technology based on other cellular processes that can generate single stranded DNA.
A significant benefit of not having to create DNA breaks, is that the RITDM™ technology avoids triggering specific DNA break repair processes, such as Non-homologous End Joining. This DNA break repair process may result in undesired mutagenic side-effects.