The invention provides a composition comprising an extraembryonic endodermal (XEN) call and/or an embryonic fibroblast (EF) cell. The invention also provides a method of establishing a XEN cell line or a primary embryonic fibroblast (EF) cell line in vitro, the method comprising culturing a zygote or parthenote from a mammal for a time sufficient to produce one or more blastocysts; and culturing the one or more blastocysts on feeder cells in culture medium for a time sufficient to produce one or a plurality of XEN cells and/or one or a plurality of EF cells.

Non-human animals and offspring thereof comprising at least one modified chromosomal sequence in a gene encoding a CD163 protein are provided. Animal cells that contain such modified chromosomal sequences are also provided. The animals and cells have increased resistance to pathogens, including porcine reproductive and respiratory syndrome virus (PRRSV). The animals and offspring have chromosomal modifications of a CD163 gene. The invention further relates to methods of breeding to create pathogen-resistant animals and populations of animals made using such methods.

The invention provides double knockout transgenic pigs (GT/CMAH-KO pigs) lacking expression of any functional GAL and CMAH. Double knockout GT/CMAH-KO transgenic organs, tissues and cells are also provided. Methods of making and using the GT/CMAH-KO pigs and tissue are also provided.

Methods, uses, and animals for introgression of alleles between animals, including SNPs. One embodiment involves introducing a targeted targeting endonuclease system and a HDR template into a cell with a mismatch in the binding of the targeting endonuclease and the targeted site.

Methods, uses, and compositions for manipulating genomic DNA. Some of the embodiments of the invention provide for making a founder animal that is completely free of all unplanned genetic modifications. Some embodiments are directed to removing genetic faults in established breeds without making other alterations to the genome. Other embodiments are directed to particular tools or processes such as TALENs or CRISPR with a preferred truncation. One embodiment involves introducing a targeted targeting endonuclease system and a HDR template into a cell (optionally with a mismatch in the binding of the targeting endonuclease and the targeted site). Another embodiment includes processes of making a genetically modified livestock animal comprising a genome that comprises inactivation of a neuroendocrine gene selective for sexual maturation, with the inactivation of the gene preventing the animal from becoming sexually mature. One embodiment includes compositions and methods for making livestock with a polled allele, including migrating a polled allele into a bovine species without changing other genes or chromosomal portions.

Methods, uses, and compositions for manipulating genomic DNA. Some of the embodiments of the invention provide for making a founder animal that is completely free of all unplanned genetic modifications. Some embodiments are directed to removing genetic faults in established breeds without making other alterations to the genome. Other embodiments are directed to particular tools or processes such as TALENs or CRISPR with a preferred truncation. One embodiment involves introducing a targeted targeting endonuclease system and a HDR template into a cell (optionally with a mismatch in the binding of the targeting endonuclease and the targeted site). Another embodiment includes processes of making a genetically modified livestock animal comprising a genome that comprises inactivation of a neuroendocrine gene selective for sexual maturation, with the inactivation of the gene preventing the animal from becoming sexually mature. One embodiment includes compositions and methods for making livestock with a polled allele, including migrating a polled allele into a bovine species without changing other genes or chromosomal portions.

Livestock animals and progeny thereof comprising at least one edited chromosomal sequence that alters expression or activity of a somatostatin receptor (SSTR) protein are provided. Livestock animal cells that contain such edited chromosomal sequences are also provided. The livestock animals have improved growth performance and weight gain. Methods for producing livestock animals with increased growth performance are also provided.

Methods, uses, and compositions for manipulating genomic DNA. Some of the embodiments of the invention provide for making a founder animal that is completely free of all unplanned genetic modifications. Some embodiments are directed to removing genetic faults in established breeds without making other alterations to the genome. Other embodiments are directed to particular tools or processes such as TALENs or CRISPR with a preferred truncation. One embodiment involves introducing a targeted targeting endonuclease system and a HDR template into a cell (optionally with a mismatch in the binding of the targeting endonuclease and the targeted site). Another embodiment includes processes of making a genetically modified livestock animal comprising a genome that comprises inactivation of a neuroendocrine gene selective for sexual maturation, with the inactivation of the gene preventing the animal from becoming sexually mature. One embodiment includes compositions and methods for making livestock with a polled allele, including migrating a polled allele into a bovine species without changing other genes or chromosomal portions.

Provided is an SgRNA combination, comprising an SgRNA specifically targeting the GGTA1 gene, an SgRNA specifically targeting the CMAH gene and an SgRNA specifically targeting the 4GalNT2 gene. Also provided is a CRISPR/Cas9 vector combination, comprising a GGTA1-CRISPR/Cas9 vector, a CMAH-CRISPR/Cas9 vector and a 4GalNT2-CRISPR/Cas9 vector. Also provided is an applicaton of the CRISPR/Cas9 vector combination in knocking out the GGTA1 gene, the CMAH gene and the 4GalNT2 gene. The knockout rates of the three genes with the specifically targeted SgRNA sequences are respectively 56%, 63%, and 41%. A three genes knockoutpig can be obtained, wherein the three genes related to immune rejectionare knocked out, and heart valves of said pig can be acquired.

The present disclosure provides methods of generating multiplexed genetically modified animals, for example, porcine endogenous retrovirus (PERV)-inactivated pigs. The disclosure also provides methods of improving the birth rate of multiplexed genetically modified animals. In some embodiments, the present closure is concerned with the generation and utilization of porcine cells in which porcine endogenous retroviral (PERV) elements have been inactivated. In sonic embodiments, the PERV-free or PERV-reduced porcine cells are cloned to produce porcine embryos. In some embodiments, the PERV-free or PERV-reduced embryos may be grown into adult swine from which organs and/or tissues may be extracted and used for such purposes as xenotransplantation into non-porcine animals such as humans.