As　a　protein　originally　found　in　plant　pathogenic　bacteria,　transcription　activator-like　effectors　(TALEs)　can　be　fused　with　the　cleaving　domain　of　restriction　endonuclease　(For　example　Fok　I)　to　form　artificial　nucleases　named　TALENs.　These　proteins　are　dependent　on　variable　numbers　of　tandem　Repeats　of　TALEs　to　recognize　and　bind　DNA　sequences.　Each　of　these　repeats　consists　of　a　set　of　approximately　34　amino　acids,　composed　of　about　32　conserved　amino　acids　and　2　highly　variable　amino　acids　called　repeat　variant　di-residues　(RVDs).　RVDs　distinguish　one　TALE　from　another　and　can　make　TALEs　have　a　simple　cipher　for　the　one-to-one　recognition　for　proteins　and　DNA　bases.　Based　on　this,　in　theory,　artificially　constructed　TALENs　could　recognize　and　break　DNA　sites　specifically　and　arbitrarily　to　perform　gene　knockout,　insertion　or　modification.　We　reviewed　the　development　of　this　technology　in　multi-level　and　multi　species,　and　its　advantages　and　disadvantages　compared　with　ZFNs　and　CRISPR/Cas　technology.　We　also　address　its　special　advantages　in　industrial　microbe　breeding,　vector　construction,　targeting　precision,　high　efficiency　of　editing　and　biological　safety.　©　2015　by　the　Institute　of　Microbiology,　the　Chinese　Academy　of　Sciences　and　the　Chinese　Society.