CRISPR: Gene-edited pigs could transform farming by next year

Unlike CRISPR, current vaccines offer limited relief, while the use of antibiotics to treat infected pigs can further complicate matters
The image shows pigs on a farm. — Pexels
The image shows pigs on a farm. — Pexels

American farmers are edging closer to a breakthrough in breeding genetically modified pigs with immunity to one of the most lethal diseases affecting the species. However, despite the potential for significant cost savings and the mitigation of porcine reproductive and respiratory syndrome (PRRS), some ethical concerns persist among animal rights organisations, viewing this advancement as a mere temporary fix within industrial farming practices.

PRRS poses a significant threat to millions of pigs globally, annually costing farmers up to $2.7 billion. Current vaccines offer limited relief, while the use of antibiotics to treat infected pigs can further complicate matters by promoting the development of antibiotic-resistant bacterial diseases.

Genus, an international breeding company, believes the solution lies in genetically engineering pigs incapable of contracting the virus. Using CRISPR gene editing technology, Genus researchers successfully removed a protein segment called CD163, rendering the pigs impervious to the virus.

A recent study published in The CRISPR Journal showcased the effectiveness of this approach, emphasising that the modified pigs maintained normal health and behaviour.

However, the process is not without challenges. Only a fraction of the piglets bred by Genus possessed the desired gene, and even then, the modification was limited to specific body cells due to mosaicism. Additionally, some genetically edited pigs exhibited unintended genome alterations.

Despite these hurdles, Genus claims to have produced hundreds of PRRS-immune pigs and anticipates FDA approval for public sale as early as next year. Concurrently, efforts are underway to secure regulatory clearance in countries like China and Mexico, both major importers of US pork.

Critics of factory farming and animal rights advocates argue that addressing livestock living conditions is paramount, rather than solely focusing on disease susceptibility. According to World Animal Protection, three-quarters of global antibiotic supplies are consumed by farm animals annually, contributing to the rise of treatment-resistant superbugs, particularly in confined and poorly ventilated factory farm environments.

Gene Bauer, President and Co-Founder of Farm Sanctuary, emphasises the need to tackle the root causes of livestock diseases by improving living conditions rather than relying solely on genetic engineering solutions.