Recent advances in the development of new transgenic animal technology

Abstract

Transgenic animal technology is one of the fastest growing biotechnology areas. It is used to integrate exogenous genes into the animal genome by genetic engineering technology so that these genes can be inherited and expressed by offspring. The transgenic efficiency and precise control of gene expression are the key limiting factors in the production of transgenic animals. A variety of transgenic technologies are available. Each has its own advantages and disadvantages and needs further study because of unresolved technical and safety issues. Further studies will allow transgenic technology to explore gene function, animal genetic improvement, bioreactors, animal disease models, and organ transplantation. This article reviews the recently developed animal transgenic technologies, including the germ line stem cell-mediated method to improve efficiency, gene targeting to improve accuracy, RNA interference-mediated gene silencing technology, zinc-finger nuclease gene targeting technology and induced pluripotent stem cell technology. These new transgenic techniques can provide a better platform to develop transgenic animals for breeding new animal varieties and promote the development of medical sciences, livestock production, and other fields.

Spermatogonial stem cells: Current biotechnological advances in reproduction and regenerative medicine

“…Interestingly, SSC mediated rat transgenesis was achieved in 2007 [78] while parallel efforts with ES cells on this species were only successful until 2010 [79] . Just recently, ES cells from domestic animals could be obtained for gene targeting goals [80] . Advances with farm animal SSCs continued in parallel.…”

Exogenous enzymes upgrade transgenesis and genetic engineering of farm animals

“…It has been postulated that the co-delivery of transgene and a site-specific RE could increase efficiency of integration into the host genome by three non-excluding ways: (1) protecting the ends of the transgene constructs, (2) inducing DNA breaks, and (3) stimulating endogenous DNA repair mechanisms [30].…”

“…Transgenic farm animals can serve as excellent models of human diseases, of biopharming, and of basic research [1][2][3][4][5]. During the past few years, transgenic farm animals have gained renewed popularity, because of the availability of annotated genome depositories (http://www.ensembl.…”

“…The exogenous enzymes are only transiently present; however, by carefully selecting highly active or hyperactive variants [8][9][10][11], the desired genetic modification can be performed in individual cells, such as the mammalian zygote. Prominent examples are hyperactive transposon systems, such as Sleeping Beauty [9,10], piggyBac [11], as well as designer nucleases, including zinc finger nucleases (ZFNs), transcription activator-like element nucleases (TALENs) and RNA-guided nucleases [1][2][3]12]. In addition, Cre recombinase and UC31 integrase found some interest for farm animal transgenesis [13,14].…”

A 90-day subchronic study of rats fed lean pork from genetically modified pigs with muscle-specific expression of recombinant follistatin

“…For example, biotechnological applications have enhanced the disease resistance of pigs, improved the feed utilization rate, and improved the lean meat percentage in a short time and with more precision. Genetic modification has been widely applied to several edible animals, including rabbits, cattle, pigs and sheep (Houdebine, 2000;Miao, 2013). Transgenic pigs have been under development for many years, with the research primarily focused on disease resistance or nutrition improvement.…”