A method is provided of targeted genome editing of an animal using site specific homologous integration. A composition comprising a single stranded oligonucleotide or double stranded nucleic acid molecule comprising a nucleic acid molecule of interest and sequences flanking a target locus cleavage site is injected into the zygote of an animal along with a nuclease and a guide nucleic acid molecule that targets the nuclease to a target locus. The composition is injected into the zygote after fertilization and prior to formation of a nucleus. The nucleic acid molecule of interest is recombined into the genome with high efficiency. The process allows for integration of nucleic acid molecules into the genome of animals in which the pronuclei cannot be visually observed during injection.
