Genetically modified pigs and methods for creating them

Abstract

The invention relates to a useful method and preparation for the prevention of porcine reproductive and respiratory syndrome virus (PRRSv) in animals, including animals of the species scrofa. The invention relates to pigs in which at least one allele of the CD163 gene has been inactivated, and specific methods and nucleic acid sequences used in gene editing to inactivate the CD163 gene. Pigs in which both alleles of the CD163 gene have been inactivated to resist porcine reproductive and respiratory syndrome virus (PRRSv). The best strains contain homozygous modified CD163 genes that retain their desirable traits.