Development of chicken embryo culture techniques provides precise methods for the manipulation of early chicken embryos and has made it possible to analyse the results of themanipulation in hatched chickens. Various attempts have been made to introduce exogenous DNA into the chicken germline, but an efficient method for producing transgenic chickensby non-viral methods has not yet been devised. Since the system for producing germline cimaeric chickens has been established by the transfer of primordial germ cells isolated from early stage embryos, manipulation of primordial germ cells seems to be one of the mostpromising methods for genetic manipulation in chickens.
