The difficulty of context-dependent binding preference between individual finger domains of ZFNs make designing of programmable ZFNs difficult even though solutions have been drawn up to address this limitation as extensive screening is necessary ( Sander, et al. 2011). TALENs, on the other hand, express lesser context-dependent binding preference and their modular assembly makes it possible to target any possible DNA sequence (Maeder, et al. 2013).
Biological cloning methods are required for the assembly of DNA encoding the repetitive domains of TALENs which can be costly. But now with the arrival of CRISPR system, genome engineering technology has shown great results in tackling issues relevant to modular DNA-binding protein construction. The ease of customization to target any desired DNA sequence in a genome simply through customized sgRNA is the reason why the CRISPR system has been used in variety of studies. This essay will talk about the implications of CRISPR towards medical and research.