Fate of exogenous DNA carried into mouse eggs by spermatozoa.

Abstract Mouse spermatozoa carried pSV2‐gpt DNA in the culture medium Into eggs at fertilization in vitro. The exogenous DNA in the fertlized eggs could be detected by PCR analysis even at their hatched biastocyst stages. However, none of 130 mice resulted from such embryos was transgenic, while microinjection of the DNA into pronuclei of fertilized mouse eggs produced 13 transgenic mice out of 146 born.