CRISPR-Cas9 was adapted from a naturally happening gene-editing process in bacteria. Whenever viruses attack bacteria they inject there own code of DNA into the bacteria and if the bacteria survives this attack, it stores the virus’s DNA in a DNA archive called CRISPR. When the same virus or any virus of the same strain attacks the bacteria again, the bacteria quickly produces an RNA from the stored DNA and uses the Cas-9 protein to scan through to find the exact match of virus DNA. If it does find a match, it removes that DNA protecting the bacteria from the virus.
The CRISPR-Cas9 scheme works likewise in the lab. Examiners create a small portion of RNA with a short “guide” arrangement that attributes (binds) to a precise target arrangement of DNA in a gene. The RNA also muddles to the Cas9 enzyme. As in microbes, the adapted RNA is used to identify the DNA arrangement, and the Cas9 enzyme punctures the DNA at the battered location. Even though Cas9 is the enzyme that is used most frequently, certain other enzymes like Cpf1 (CRISPR-associated endonuclease in Prevotella and Francisella 1) can also be used. Once the DNA is cut, investigators use the cell’s DNA repair gear to add or delete pieces of inherited material or to make variations to the DNA by substituting prevailing section with a tailored DNA sequence.
Read More about CRISPR