Genome Editing in the Chicken: From PGC-Mediated Germline Transmission to Advanced Applications

Avian genome editing has historically lagged behind mammalian research. This disparity is primarily due to a unique reproductive biology that precludes standard techniques like pronuclear injection. A pivotal breakthrough, however, came from the development of efficient in vitro culture systems for primordial germ cells (PGCs). This has established the chicken as a tractable and powerful model for genetic engineering. Our review chronicles the technological evolution this has enabled, from early untargeted methods to the precision of modern CRISPR-based systems. We then analyze the broad applications of these tools, which are now used to engineer disease resistance, enhance agricultural traits, and develop novel platforms such as surrogate hosts and oviduct bioreactors. Collectively, these advances have established PGC-based genome editing as a robust and versatile platform. Looking forward, emerging precision editors and the expansion of these techniques to other avian species are poised to drive the next wave of innovation in poultry science and biotechnology.