The present invention relates to a genetically modified pig comprising at least one site for integration of at least one transgene. The invention also pertains to a porcine embryo, blastocyst, foetus, donor cell and/or cell nucleus, derived from said genetically modified pig. In another aspect, the invention relates to any genetically modified porcine blastocyst, wherein the genetically modified genome comprises at least one site for integration of at least one transgene.