The concept of DNA engineering (also known as DNA manipulation, DNA technology, and DNA recombination) is controversial, and the process of DNA engineering is amazing. DNA engineering is the altering of DNA, with the purpose usually being to mass produce some kind of chemical. Contrary to popular belief, DNA engineering, as of today, is not used to change the physical characteristics of an individual. However, some day in the future, that might be very common (it would be used to prevent hereditary diseases).
DNA engineering is a complex process which has many steps and requires many tools. As of today, DNA engineering is used to mass produce products like insulin. If you've ever wondered how chemicals like insulin can be mass produced and used by humans, it will be explained here. But before understanding how this DNA manipulation works, some things need to be known about an unlikely ally: Bacteria.
Bacteria are crucial to the process of DNA engineering, and without them we wouldn't be able to make use of it. Bacteria are easy to clone and it's easy to alter their DNA. In fact, bacteria alter their own DNA through three processes, but for the purpose of DNA engineering, scientists are only concerned with one. Transformation is when bacteria take DNA from surrounding fluid and incorporate it into their own. Bacteria also have small circular rings of DNA called plasmids, which is the DNA that is actually altered in the bacteria.
There are many steps to recombining DNA. First, a suitable bacterium must be taken, as well as a cell containing a gene that scientists want to clone. The scientists isolate the bacterium's plasmid as well as the cell's DNA. Then, the scientists use something called a restriction enzyme on both the cell DNA and the bacterium's plasmid. The restriction enzyme cuts out the gene of interest, the one the scientists want to clone, and then it is placed near the bacterial plasmid and it attaches (in the gap of the plasmid that was taken out with the restriction enzyme). However, the hydrogen bonds formed when the DNA connects aren't very strong, and an enzyme called DNA ligase is used to seal the cell DNA to the plasmid by covalent bonds. Now, the plasmid has now become recombinant DNA, and is ready to be cloned. The bacterium is allowed to multiply into several bacteria, and then scientists can use the huge amounts of bacteria for something useful.
One thing scientists can do is use restriction enzymes to cut out the cloned gene (which was cloned when the bacteria reproduced), and place it in another organism, whether it is human or plant. By placing a new gene into a plant, it might give that plant a resistance to something, like certain bugs. Or, the gene can be allowed to stay in the bacteria and they mass produce the protein the DNA gene codes for, like insulin. So, for example, lots of insulin is produced, extracted, packed, and is ready for use by humans.
The same concept can be applied to any other gene or protein that needs to be mass produced. By using this technique, scientists can mass produce any gene or protein they want, and use it to benefit humans. It is not long before human babies' DNA is altered to fix hereditary diseases, and things like hemophilia and sickle cell disease will be problems of the past.