Genome edited sheep and cattle

Abstract

Genome editing tools enable efficient and accurate genome manipulation. An enhanced ability to modify the genomes of livestock species could be utilized to improve disease resistance, productivity or breeding capability as well as the generation of new biomedical models. To date, with respect to the direct injection of genome editor mRNA into livestock zygotes, this technology has been limited to the generation of pigs with edited genomes. To capture the far-reaching applications of gene-editing, from disease modelling to agricultural improvement, the technology must be easily applied to a number of species using a variety of approaches. In this study, we demonstrate zygote injection of TALEN mRNA can also produce gene-edited cattle and sheep. In both species we have targeted the myostatin (MSTN) gene. In addition, we report a critical innovation for application of gene-editing to the cattle industry whereby gene-edited calves can be produced with specified genetics by ovum pickup, in vitro fertilization and zygote microinjection (OPU-IVF-ZM). This provides a practical alternative to somatic cell nuclear transfer for gene knockout or introgression of desirable alleles into a target breed/genetic line.

Intracytoplasmic sperm injection in domestic and wild mammals

“…Moreover, after the generation of the first transgenic piglet by sperm injection, ICSI gained importance as a new tool for inducing genetic modifications in farm animals (Kurome et al 2006, Garcia-Vazquez et al 2010. However, the advent of CRISPR-Cas9 system for genetic engineering lead to the replacement of ICSI by regular or IVF zygotes for the generation of genetically modified animals (Hai et al 2014, Whitworth et al 2014, Proudfoot et al 2015, Wang et al 2015, Bevacqua et al 2016.…”

“…In conclusion, ICSI-MGT in farm animal has only produced repeatable results in pigs, wherein several transgenic offspring have resulted. However, interest in producing transgenic animals by ICSI-MGT has decreased with the advent of new tools of gene edition (CRISPR-Cas9 and TALEN system), which are technically simpler (Hai et al 2014, Whitworth et al 2014, Proudfoot et al 2015, Wang et al 2015, Bevacqua et al 2016). …”

Genome Editing with Engineered Nucleases in Economically Important Animals and Plants: State of the Art in the Research Pipeline

“…The knock-out of the mstn gene thus results in a substantial increase of skeletal muscle mass and in increased meat production. Using SDNs, the gene was artificially mutated in cattle Proudfoot et al, 2015) and pigs (Huang et al, 2014b;Qian et al, 2015;Wang et al, 2015b), but also in smaller livestock species like sheep Zhang et al, 2014a;Crispo et al, 2015;Proudfoot et al, 2015) and goat (Ni et al, 2014;Wang et al, 2015c). In most cases, the studies have chosen to target the first exon of the gene and obtained small deletions and insertions in the gene.…”

“…In most cases, the studies have chosen to target the first exon of the gene and obtained small deletions and insertions in the gene. In the studies of Proudfoot et al (2015), Han et al (2014), Luo et al (2014), Crispo et al (2015), Wang et al (2015c), and Wang et al (2015a) several offspring were born that had the desired mstn knock-out. The animals were visually different from the wild type individuals with an obvious difference in muscle mass and a difference was also observed during histological comparison of the muscles Qian et al, 2015).…”

“…Apart from model plant and animal species, studies have been carried out with economically important organisms and promising results have been obtained. However, a majority of the studies have achieved the mutation only at the cellular level and only a few went on to produce a full-grown organism; especially in the case of animals where the process is more complicated and time-consuming (Shukla et al, 2009;Yu et al, 2011;Lillico et al, 2013;Han et al, 2014;Haun et al, 2014;Luo et al, 2014;Wang et al, 2014;Clasen et al, 2015;Proudfoot et al, 2015). The full-grown animals have been reported to live up to several months of age, but it is not clear yet whether they will maintain normal physiological function through to the adulthood (i.e.…”