Genome engineering models are important tools, which are widely used in life science research, such as gene function research, cancer research and drug discovery. Eukaryotic genomes contain billions of DNA bases and are difficult to manipulate. To overcome this barrier, a series of programmable nuclease-based genome editing technologies have been developed. The most rapidly developing technology is the class of RNA-guided endonucleases known as Cas9 from the CRISPR system. Cas9 can be easily targeted to virtually any genomic location of choice by guide RNA. The ease of Cas9 targeting, high efficiency and the possibility for highly multiplexed modification broaden the application of CRISPR/Cas9 system from basic research to biotechnology and medicine. In term of the development of CRISPR/Cas9 system, the generation of genome engineering models becomes easy, fast and low-cost.
