Directly reprogramming a cell's identity with gene editing

Researchers have used CRISPR—a revolutionary new genetic engineering technique—to convert cells isolated from mouse connective tissue directly into neuronal cells. 

In 2006, Shinya Yamanaka, a professor at the Institute for Frontier Medical Sciences at Kyoto University at the time, discovered how to revert adult connective tissue cells, called fibroblasts, back into immature stem cells that could differentiate into any cell type. These so-called induced pluripotent stem cells won Yamanaka the Nobel Prize in medicine just six years later for their promise in research and medicine.

Since then, researchers have discovered other ways to convert cells between different types. This is mostly done by introducing many extra copies of "master switch" genes that produce proteins that turn on entire genetic networks responsible for producing a particular cell type.

Now, researchers at Duke University have developed a strategy that avoids the need for the extra gene copies. Instead, a modification of the CRISPR genetic engineering technique is used to directly turn on the natural copies already present in the genome.

These early results indicate that the newly converted neuronal cells show a more complete and persistent conversion than the method where new genes are permanently added to the genome. These cells could be used for modeling neurological disorders, discovering new therapeutics, developing personalized medicines and, perhaps in the future, implementing cell therapy.