Chinese scientists report gene editing tool better than CRISPR

In some cases, not all cells within a treated organism or tissue may undergo the desired gene editing, leading to mosaicism, a situation where a person has two or more genetically different sets of cells in his or her body. Because some cells contain the desired genetic changes while others do not, this can make it more difficult to use certain therapeutic procedures.

It can also be challenging to effectively deliver CRISPR components (Cas9 and guide RNA) into target cells or tissues. For many purposes, multiple delivery techniques may be necessary.

Finally, there is a chance that when CRISPR is used for gene therapy in people, the immune system would mistake the Cas9 protein for something foreign and launch an immunological reaction, which could limit how effective the treatment is.

Some of these problems can be resolved with CyDENT, claim the scientists from the Chinese Academy of Sciences Institute of Genetics and Developmental Biology. This is because the new tool has the capacity to undertake strand-specific gene editing without any cuts.

Created using a protein-based approach

Kevin Zhao, one of the study’s authors and co-founder of Suzhou-based Qi Biodesign, told SCMP that, in order to better access hard-to-reach cell genomes, CyDENT was created using a "protein-based approach" that relies on a protein signal to carry the editor inside, foregoing the requirement for a guide RNA.

Zhao further explained that CRISPR-based systems depend on a guide RNA to function, which may not be a problem when editing the DNA in a cell's nucleus but becomes one when modifying the DNA in a plant's chloroplast or a human mitochondria. Guide RNA is a piece of RNA designed by researchers to use Cas9 for gene editing.

Zhao told SCMP that, although more research needed to be done to ensure the safety and effectiveness of the new approach in human therapies, the instrument has already demonstrated great promise for studying previously un-editable DNA.

The team now has ambitious plans to "start exploring" what they can accomplish in plant chloroplasts. If the researchers have indeed engineered a superior form of gene editing, then the approach has the potential to revolutionize medicine, agriculture, and biotechnology.

However, as with all things that alter genes, great caution and oversight are needed. Challenges and concerns pertaining to the new technique must first be addressed through rigorous research, ethical guidelines, and responsible regulation.