Production of transgenic birds using pantropic retroviral vectors

Transgenic birds are expected to be a new class of transgenic bioreactor, because an egg contains high concentration of proteins such as ovalbumin and antibodies. However, the difficulty of gene transfer to avian embryos poses a limitation for the efficient germ-line transmission of foreign DNA. In the present study, we used a replication-defective pantropic retroviral vector pseudotyped with vesicular stomatitis virus G protein (VSV-G) to produce transgenic quails. The viral solution, in which the titer was increased up to 10(9) cfu/ml by ultracentrifugation, was injected into blastodermal stage embryos, and the embryos were incubated to hatch. The G(0) transgenic quails mated with non-transgenic quails produced G(1) transgenic quails with very high frequency of germ-line transmission of vector DNA.