Researchers used a genetic tool called CRISPR/Cas9 to alter individual letters of the pig’s genetic code.

Technique could boost efficiency of farmed pigs

Scientists at the University of Edinburgh’s Roslin Institute have announced a new gene-editing advance that could help to improve stocks of farmed pigs.

The technique takes stem cells from male pigs with desirable characteristics - like greater resilience to disease - and transplants them into surrogates to produce limitless supplies of their sperm.

The scientists say that the surrogates have functional testes, but do not have specialised stem cells that are needed to produce sperm containing their own genetic information.

“This could dramatically improve the production efficiency and quality of farmed pigs, as well as enhancing other desirable traits such as disease resilience in production animals,” said Professor Bruce Whitelaw, head of developmental biology at the University of Edinburgh’s Roslin Institute.

In the study, researchers used a genetic tool called CRISPR/Cas9 to alter individual letters of the pig’s genetic code. This led to the inactivation of a gene called NANOS2.

The researchers found that pigs with two copies of the DNA change do not have sperm stem cells and cannot produce sperm, making them completely sterile.

All other aspects of testicular development were completely unaffected and the animals are otherwise healthy. Female pigs were also unaffected by the change to their genetic code.

Pigs with only one copy of the DNA change are still fertile and could be used to produce more of the surrogate animals using conventional breeding techniques, researchers explain.

The team says the breakthrough will forever allow farmers to preserve sperm from prized animals.