TRANSGENESIS IN CHICKENS

The application of transgenic technology to domestic poultry offers an alternative means to conventional practice for improvement of this hi ghly productive agricultural species. The hen's reproductive system ha s unique characteristics which have imposed limitations on the use of established methods for artificial gene transfer. In this article, we review the various strategies that have been adopted to overcome the p roblem. Target sites for gene insertion include the fertilized ovum, t he blastodermal embryo in the unincubated egg, and the primordial germ cells. Notable success in obtaining somatic and germline transformati on has been achieved with the use of retroviral vectors to infect the blastodermal embryo. Current attempts to introduce DNA directly into t he genome, without resort to pathogen-derived vectors, are discussed.