Transgenic birds from transformed primordial germ cells.

Primordial germ cells (PGCS) are the progenitor cells for the gametes. They can be obtained from avian embryos by dissociating the germinal crescent region, where they accumulate, or by sampling the blood at the time of their migration to the gonad. PGCS were obtained from these sources and transfected with defective retroviruses. These manipulated cells were injected into recipient embryos to form chimaeras which grew to sexual maturity and produced offspring, some of which contained the foreign DNA. This is the first example of the direct use of PGCS to produce transgenic offspring.