Advance in Genome Editing Technologies for Livestock Improvement

Genome editing is a novel technology which enables targeted biological genome modification. It can boost the transgenic efficiency,realize knockout livestock gene and fix targeted integration. Recently,zinc finger nucleases( ZFN),transcription activator-like effector nucleases( TALEN) and bacterial clustered regularly interspaced short palindromic repeats( CRISPR) adaptive immunity system,have been used to cleave the double-strand DNA at specific site,followed by endogenous DNA repair,which can lead to homologous recombination repair and nonhomologous end joining. These techniques,therefore,make precise changes to the DNA of living cell by knocking out a gene,fixing targeted integration or replacing DNA fragment at the specific site. Many breakthroughs have been achieved recently using this technology,especially in the improvement of certain important production traits,such as meat quality,growth rate and disease resistance,etc. on pigs,cattle,sheep and other livestock. Genome editing technology makes it possible to efficiently improve livestock on fixed point of genes,which will definitely exert a profound impact on the development of industrialization of transgenic animal.