The present invention provides improved methods and compositions for the generation of transgenic non-human animals. The present invention permits the introduction of exogenous nucleic acid sequences into the genome of unfertilized eggs (e.g., pre-maturation oocytes and pre-fertilization oocytes) by...http://www.google.es/patents/US6291740?utm_source=gb-gplus-sharePatente US6291740 - Transgenic animals
