Zhang Feng team successfully developed the "new" gene scissors

a paper published in the British journal Nature Communications, Zhang Feng of the Massachusetts Institute of Technology-Harvard University's Broad Institute reported on a third CRISPR-Cas system that can edit the genomes of human cells. In the experiment, the CRISPR-Cas12b system showed higher specificity to the target sequence than the well-known Cas9.
CRISPR gene editing technology is known as the "game changer" in the life sciences, a breakthrough technology that discovers, removes, and replaces specific parts of DNA with a specially programmed enzyme called Cas9, making CRISPR-Cas9 a versatile genome editing system.
Cas9 is not the only RNA-directed nuclease (an enzyme that cuts DNA) in the Cas protein family. In addition to Cas9, the researchers found Cas12a and Cas12b. Cas12a has been developed as a genome editing tool, while Cas12b has not yet been fully developed, at least in part because of its heat-addicted properties.
Zhang Feng and colleagues studied Cas12b because the protein is smaller than Cas9 or Cas12a and is easier to deliver between cells through viral vectors. But cas12b of the original structure cuts the non-target single strand in the double-stranded DNA. To solve this problem, the team redesigned Cas12b to enhance its activity at human body temperature (37 degrees C). Compared with Cas9, the redesigned Cas12b has a higher specificity to the target sequence in cell culture experiments.
researchers say much remains to be done to transform Cas12b into a tool as widely used as Cas9, but the emergence of a third potential genome editing system will give researchers around the world more options.
comes after CRISPR sparked a patent war over its huge commercial value. The U.S. Patent and Trademark Office's Patent Trial and Appeals Board appealed after a key ruling in February 2017, and the U.S. Court of Appeals for the Federal Circuit upheld the ruling in September 2018, with Zhang Feng's agency continuing to prevail. (Source: Science and Technology Daily Zhang Mengran)