Production of Human Insulin.

Gene transfer involves essentially the following stages :

1. Isolation of Donor or DNA segment. A useful DNA segment is isolated from the donor organism.

2. Formation of Recombined DNA (rDNA). Both the vector and donor DNA segments are cut in the presence of restriction endonuclease. In the presence of ligase DNA segments of both are joined to form rDNA

3. Production of Multiple Copies of rDNA. Next step in the process is production of multiple copies of this recombinant DNA.

4. Introduction of rDNA in the recipient organism. This rDNA is inserted into a recipient organism.

Steps involved in gene transfer for the production of human insulin.

5. Screening of the transformed cells. The recipient (host) cells are screened in the presence of rDNA and the product of donor gene. The transformed cells are separated and multiplied, an economical method for its mass production.