What is CRISPR?

Genetic engineering is not a new idea. The Human Genome Project produced a complete genetic blueprint for building a human being in 2003. However, while genome editing tools like Zinc finger nuclease (ZFN) and Transcription activator-like effector nuclease (TALEN) have existed for some time, researchers have been struggling for years to manipulate the genome more simply, effectively and safely.

The new genome-editing technology called CRISPR is changing all that. CRISPR takes genomic engineering to the next level. It provides a precise and remarkably easy way to edit DNA at the cellular level. It is now possible to identify a DNA sequence, remove it, replace it or add to it more easily than ever before.

The CRISPR technology is derived from a bacterial host defence mechanism against invading foreign genetic elements such as plasmids or bacteriophages. Upon infection, sequences derived from invading bacteriophage are incorporated into the bacterial genome and form stretches of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats). CRISPRs are often associated with Cas (CRISPR associated) proteins necessary for the integration of bacteriophage DNA and for the acquired immune response in bacteria.

The CRISPR/Cas system has been used for gene editing (adding, disrupting or changing the sequence of specific genes) and gene regulation in a large range of species, including human cells. By delivering the Cas9 protein, an RNA-guided endonuclease, and the appropriate guide RNA (gRNA) into a cell, an organism’s genome can be cut and modified at any desired location. Watch this video to understand more about how CRISPR works.