CRISPR-Cas

CRISPR-Cas can be seen as scissors that can ‘cut’ the DNA in a very specific place. Originally these scissors were found in a bacterium that can protect itself with these scissors against an attack of a virus. When the virus enters the bacterium, the scissors of the bacterium cut into the viral DNA. The virus becomes ineffective and cannot kill the bacteria. The beauty of this system is that it can be introduced into the cells of all organisms. So not only in plants, but also in animals and humans.

Researchers can easily customize the scissors and make them specific to any blinking area. This adjustment is done by making the ‘guide molecule’, which consists of RNA, look like the blink site in the DNA.

CRISPR-Cas is usually based on CRISPR-Cas9. But instead of Cas9, other Cas-like components can also be used, which is why it is now commonly referred to as CRISPR-CAS or CRISPR technology.

The possibilities of CRISPR-Cas are endless. An example of this is the development of apples and mushrooms that no longer turn brown. This can be done by cutting the DNA that encodes the property for browning. These products have already been marketed in America.

In animals, CRISPR-Cas has been applied by cutting the DNA that codes for cornea formation in cattle. Human applications are also being considered. By altering the DNA that causes a serious disease, lives can potentially be saved. However, the modified genetic trait is passed on to offspring. Of course, this calls for an ethical debate, which needs to be conducted in society.

However, CRISPR-Cas can also be used in human cells in such a way that the property is not passed on to offspring. Then a completely different type of cell is used, for example one that is involved in the immune system. Such cells can be isolated from the blood, used for genome editing, and returned to the patient without transfering thie trait to their offspring.

A very special application of CRISPR-Cas is the development of a gene drive.