Gene editing switches off pig viruses

Technique overcomes barrier to pig–human organ transplants.

The CRISPR–Cas9 gene-editing technology can be used to generate pigs that are free from viruses that could potentially infect humans.

Researchers hope that pigs might one day be able to serve as organ donors when no human organ is available. But there are concerns that viruses embedded in the pig genome could infect humans who have porcine transplants.

Luhan Yang at eGenesis in Cambridge, Massachusetts, and her colleagues injected pig cells with a CRISPR–Cas9 gene-editing system that inactivated all copies of porcine endogenous retroviruses (PERVs) from the cells. They then transferred the nuclei of these cells into pig embryos, which they implanted into sows whose genomes contained PERVs. When piglets were born, the researchers found that 100% of the PERVs in their cells had been inactivated.

The authors say that this PERV-inactivated pig strain can be a resource for researchers developing pigs with human-like organs.