How is DNA inserted, deleted, or replaced?

In the previous page, we explained how DNA is put into cells, but now how is that DNA actually introduced into the cell's DNA?

Gene Targeting

The first method of DNA manipulation is "gene targeting". This method is done as follows.

First, the gene to be introduced is added to the same DNA as the cell, or the deleted DNA is put into the cell. This DNA is called "donor DNA". When the donor DNA is inserted, a certain probability of pairing occurs between the DNA that was originally in the cell and the donor DNA, and the DNA with the introduced or deleted gene is copied starting from this pairing. This mechanism is called "homologous recombination" (HR).

Transgenic technology

In addition to gene targeting, there is another method called "transgenic technology". In transgenic technology, the gene to be introduced is placed in the nucleus of the cell and incorporated into the DNA. However the biggest problem with this technology is that the gene cannot be inserted at the target location. If it cannot be inserted at the target location, unexpected mutations may occur.