TRANSGENIC BIRDS BY DNA MICROINJECTION

We have developed a method for production of transgenic chickens by DN A microinjection of chick zygotes followed by ex vivo embryo culture. The fate of plasmid DNA microinjected into the germinal disc of zygote s was analyzed in embryos which survived for at least 12 days in cultu re. Approximately half of the embryos contained plasmid DNA, 6% at a l evel equivalent to one copy per cell in all tissues analyzed. Seven ch icks, 5.5% of the total number of injected ova, survived to sexual mat urity. One of these, a cockerel, transmitted the exogenous DNA to 3.4% of his offspring. These G1 birds have reached sexual maturity and hav e been bred to produce transgenic offspring, demonstrating that stable transmission of foreign DNA can be obtained by our method.