text: TALEN has been used to efficiently modify plant genomes, creating economically important food crops with favorable nutritional qualities.  They have also been harnessed to develop tools for the production of biofuels.  In addition, it has been used to engineer stably modified human embryonic stem cell and induced pluripotent stem cell (IPSCs) clones and human erythroid cell lines, to generate knockout C. elegans, knockout rats, knockout mice, and knockout zebrafish. Moreover, the method can be used to generate knockin organisms. Wu et al.obtained a Sp110 knockin cattle using Talen nickases to induce increased resistance of tuberculosis. This approach has also been used to generate knockin rats by TALEN mRNA microinjection in one-cell embryos.
  TALEN has also been utilized experimentally to correct the genetic errors that underlie disease. For example, it has been used in vitro to correct the genetic defects that cause disorders such as sickle cell disease, xeroderma pigmentosum, and epidermolysis bullosa. Recently, it was shown that TALEN can be used as tools to harness the immune system to fight cancers; TALEN-mediated targeting can generate T cells that are resistant to chemotherapeutic drugs and show anti-tumor activity.
  In theory, the genome-wide specificity of engineered TALEN fusions allows for correction of errors at individual genetic loci via homology-directed repair from a correct exogenous template.  In reality, however, the in situ application of TALEN is currently limited by the lack of an efficient delivery mechanism, unknown immunogenic factors, and uncertainty in the specificity of TALEN binding.
  Another emerging application of TALEN is its ability to combine with other genome engineering tools, such as meganucleases. The DNA binding region of a TAL effector can be combined with the cleavage domain of a meganuclease to create a hybrid architecture combining the ease of engineering and highly specific DNA binding activity of a TAL effector with the low site frequency and specificity of a meganuclease.
  In comparison to other genome editing techniques, TALEN falls in the middle in terms of difficulty and cost. Unlike ZFNs, TALEN recognizes single nucleotides. It's far more straightforward to engineer interactions between TALEN DNA binding domains and their target nucleotides than it is to create interactions with ZFNs and their target nucleotide triplets. On the other hand, CRISPR relies on ribonucleotide complex formation instead of protein/DNA recognition. gRNAs have occasionally limitations regarding feasibility due to lack of PAM sites in the target sequence and even though they can be cheaply produced, the current development lead to a remarkable decrease of cost for TALENs, so that they are in a similar price and time range like CRISPR based genome editing.