[Genetic transformation of animals by the insertion of foreign genes into the zygotes].

A review of literature on genetic transformation of animal (mouse and Drosophila) germ cells by microinjection of the cloned genes into the pronuclei or into the early embryos. The fate of foreign genes and mechanisms of their integration into the recipient genome are considered in detail, as well as genetic consequences of the exogenic DNA insertion. Expression of the donor genes in transgenic animals is analyzed, its irregular and unusual pattern is noted in transgenic mice. An attempt has been undertaken not only to stress obvious advances in genetic transformation of animals, but also to outline unsolved problems related to inheritance of exogenous genes, insertion mutagenesis and irregular expression of the donor genes.