Prime Editing: More precise genetic scissors?

The Prime Editing Method (PE), developed by researchers at the Broad Institute in Cambridge/USA, is based on the well-known CRISPR-Cas9 genetic scissors.

PE is capable of exchanging, inserting or deleting individual building blocks of the genome (DNA) or generating changes in them through combinations of the forementioned methods.

Unlike the previous gene editing technique, however, PE does not cut both strands of the DNA double helix. It just cuts one.

The researchers hope that this will prevent changes in the genetic material from occurring in the wrong place. They published their findings on 21 October in the journal Nature. 

Read more: HIV completely removed from mice in groundbreaking study

Gene therapies for people with hereditary diseases

The researchers say that their new method will be able to correct up to 89 percent of all known human hereditary diseases, such as sickle cell anemia.

The method could, for example, be used in gene therapies. These treatments involve the targeted introduction of genetic information into the diseased cells of living people.

PE represents "a very promising approach for gene therapy," says Dr. Dirk Heckl, a professor of experimental pediatrics at the Martin Luther University Halle-Wittenberg, who was not involved with the research. "The efficiency shown is amazing, and [could] represent a milestone on the way to the therapeutic application of CRISPR technology in gene therapy — after independent validation."

In theory, PE could also be used to repair genetic material prior to artificial insemination. Doing so, however, is forbidden in most countries because it would represent an intervention in the human germline. 

Read more: Who's the daddy: Does it really matter where your DNA comes from?

Probable use in plant breeding

The PE method will probably be used, above all, in plant breeding — and perhaps in animal breeding — where certain characteristics are intentinoally developed.

"The technology seems to be particularly interesting for plants," said Dr. Holger Puchta, a professor of plant molecular biology and biochemistry at the Karlsruhe Institute of Technology (KIT) who has been working for a long time on introducing precise changes into plant genomes. PE could therefore "actually help to obtain disease-resistant plants, or gluten-free plant products more easily," he says.

Of course, he added, the process would have to first be tested.

Read more: CRISPR-Cas9 babies likely to die earlier, Berkeley study says