Researchers develop an engineered mini CRISPR genome editing system

The common analogy for CRISPR gene editing is that it works like molecular scissors, cutting out select sections of DNA. Stanley Qi, assistant professor of bioengineering at Stanford University, likes that analogy, but he thinks it's time to reimagine CRISPR as a Swiss Army knife.

The many different CRISPR systems in use or being clinically tested for gene therapy of diseases in the eye, liver and brain, however, remain limited in their scope because they all suffer from the same flaw: they're too large and, therefore, too hard to deliver into cells, tissues or living organisms.

In a paper published Sept. 3 in Molecular Cell, Qi and his collaborators announce what they believe is a major step forward for CRISPR: An efficient, multi-purpose, mini CRISPR system. Whereas the commonly used CRISPR systems – with names like Cas9 and Cas12a denoting various versions of CRISPR-associated (Cas) proteins – are made of about 1000 to 1500 amino acids, their "CasMINI" has 529.

The researchers confirmed in experiments that CasMINI could delete, activate and edit genetic code just like its beefier counterparts. Its smaller size means it should be easier to deliver into human cells and the human body, making it a potential tool for treating diverse ailments, including eye disease, organ degeneration and genetic diseases generally.