Synthetic biology for heritable viral disease resistance in livestock

Synthetic biology is rapidly expanding the strategies available to engineer disease resistance in livestock. Genome editing of host factors required for pathogen entry or replication has generated complete or partial resistance in pigs, cattle, and chickens, culminating in the first regulatory approvals of PRRSV-resistant pigs. Another frontier is emerging in which synthetic antiviral circuits detect and suppress infection through programmable molecular responses. Precision editing tools, including base and prime editors, may enable resistance through smaller and more targeted genomic changes, while organoid and stem cell-derived cell cultures are accelerating pre-animal validation. This review examines recent advances in host-factor engineering, synthetic antiviral systems, and enabling platforms, and considers the challenges of commercial dissemination, regulation, and public acceptance. Together, these developments position engineered resistance as a potentially important component of integrated livestock disease control.