The genome editing revolution: A CRISPR-Cas TALE off-target story

Abstract

In the last 10 years, we have witnessed a blooming of targeted genome editing systems and applications. The area was\rrevolutionized by the discovery and characterization of the transcription activator-like effector proteins, which are easier to\rengineer to target new DNA sequences than the previously available DNA binding templates, zinc fingers and\rmeganucleases. Recently, the area experimented a quantum leap because of the introduction of the clustered regularly\rinterspaced short palindromic repeats (CRISPR)-associated protein (Cas) system (clustered regularly interspaced short\rpalindromic sequence). This ribonucleoprotein complex protects bacteria from invading DNAs, and it was adapted to be used\rin genome editing. The CRISPR ribonucleic acid (RNA) molecule guides to the specific DNA site the Cas9 nuclease to cleave\rthe DNA target. Two years and more than 1000 publications later, the CRISPR-Cas system has become the main tool for\rgenome editing in many laboratories. Currently the targeted genome editing technology has been used in many fields and\rmay be a possible approach for human gene therapy. Furthermore, it can also be used to modifying the genomes of model\rorganisms for studying human pathways or to improve key organisms for biotechnological applications, such as plants,\rlivestock genome as well as yeasts and bacterial strains.