Gene edited Pigs are resistant to viruses

Through gene editing, scientists have been able to produce pigs that are resistant to PRRS. PRRS stands for Porcine Reproductive and Respiratory syndrome. This affliction can cause breathing problems and even death in young pigs. This disease is considered to be one the world's most costly animal diseases. While this seems to be a great key to helping pork producers, some farmers are concerned.

Helen Browning of the soil association fears that this genetic edit might result in less humane treatment of the animals. Browning has been farming pigs organically for 30 years and she experienced that pigs kept outdoors with a higher quality of life were less likely to develop the disease. Browning feels that if the animals are resistant, there will be little incentive to treat them humanely.

While Scientists and Farmers alike are trying to integrate these swine into the marketplace, they are still years away. Much like the debate surrounding GMOs, there is a pretty large disparity between public perception and fact. Many conversations need to occur before legislation is molded to cater to these changes. It seems that many of these genetic breakthroughs are moving faster than our government regulation.

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Scientists Breed Pigs with Life-Saving Gene Alteration

Piglets are the main focus for PRRS prevention.

Great leaps have been made in research of the pig farming industry as scientists at University of Edinburgh have managed to use gene-editing techniques to halt the infection of one of pig-farmers' worst enemies: Porcine Reproductive and Respiratory Syndrome. Porcine Reproductive and Respiratory Syndrome (PRRS) is a costly and deadly disease that plagues the domesticated pig population with high death rates for both pregnant sows, their fetuses, and young piglets. The virus can cause abortion and mummification of fetuses, as well as severe respiratory issues and extreme weight loss, which causes a large percentage of the piglet population to die before reaching adulthood. This article summarizes the discoveries and the mechanisms behind them.


The pathway for the PRRS virus has now been linked to a scavenger receptor on macrophages known as CD163, a receptor also responsible for managing inflammation and removing hemoglobin. Scientists have managed to pinpoint CD163 as the infection site for PRRS, but due to the other important contributions of CD163, they could not delete the receptor as a whole. However, in the originally published journal detailing the research, the structure of CD163 is described as "pearls-on-a-string", with nine scavenger receptor crysteine-rich domains (SRCR), and from this, the team of Edinburgh managed to pinpoint SRCR5, the domain responsible for the infection of pigs with PRRS.

Using gene-editing technologies, researchers injected 24-39 zygotes with the SRCR5 deleted genes and ended up with 32 live piglets. From this, they took the two pigs that showed the desired deletion of the exon 7 (which is linked to SRCR5), crossed them, and resulted in a mixture of different genotypes, all of which had deletion of exon 7 in varying forms. Exposing these individuals to the PRRS virus did not result in infection, while still maintaining normal functions within the CD163 scavenger receptor. From this experiment, not only did the team at Edinburgh prove that the deletion of SRCR5 can prevent infection of one of the deadliest viruses in domestic pigs, but also that it can be safely and successfully passed on to other generations.