Biology (B)

Biotechnology in Medicine and Agriculture

There are many applications of genetic information, including applications in medicine and agriculture. These applications show daily the significance of biotechnology, and the impact biotechnology has on our society.

Medicine

As mentioned above, one application of recombinant DNA technology is producing the protein insulin. Using biotechnological techniques, the specific gene sequence that codes for human insulin was introduced into the bacteria E. coli. The transformed gene altered the genetic makeup of the bacterial cells, such that in a 24 hour period, billions of E. coli containing the human insulin gene resulted, producing human insulin to be administered to patients. Recombinant DNA technology has allowed mass quantities of insulin to be produced, treating the growing population that relies on this protein.

Though the production of human insulin by recombinant DNA procedures is an extremely significant event, many other aspects of DNA technology are beginning to become reality. In medicine, modern biotechnology provides significant applications in such areas as pharmacogenomics, genetic testing (and prenatal diagnosis), and gene therapy. These applications use our knowledge of biology to improve our health and our lives. Many of these medical applications are based on the findings of the Human Genome Project.

Agriculture

Biotechnology has also led scientists to develop useful applications in agriculture and food science. These include the development of transgenic crops - the placement of genes into plants to give the crop a beneficial trait. Benefits include:

• Improved yield from crops.
• Reduced vulnerability of crops to environmental stresses.
• Increased nutritional qualities of food crops.
• Improved taste, texture or appearance of food.
• Reduced dependence on fertilizers, pesticides and other agrochemicals.

Crops are obviously dependent on environmental conditions. Drought can destroy crop yields, as can too much rain or floods. But what if crops could be developed to withstand these harsh conditions? Biotechnology will allow the development of crops containing genes that will enable them to withstand harsh conditions. For example, drought and excessively salty soil are two significant factors affecting crop productivity. But there are crops that can withstand these harsh conditions. Why? Probably because of that plant's genetics. So scientists are studying plants that can cope with these extreme conditions, trying to identify and isolate the genes that control these beneficial traits. The genes could then be transferred into more desirable crops, with the hope of producing the same phenotypes in those crops.

Thale cress (Figure below), a species of Arabidopsis (Arabidopsis thaliana), is a tiny weed that is often used for plant research because it is very easy to grow and its DNA has been extensively characterized. Scientists have identified a gene from this plant, At-DBF2, that gives the plant resistance to some environmental stresses. When this gene is inserted into tomato and tobacco cells, the cells were able to withstand environmental stresses like salt, drought, cold and heat far better than ordinary cells. If these preliminary results prove successful in larger trials, then At-DBF2 genes could help in engineering crops that can better withstand harsh environments. Researchers have also created transgenic rice plants that are resistant to a rice virus. In Africa, this virus destroys much of the rice crops and makes the surviving plants more susceptible to fungal infections.

CK-12 Foundation, Biology. http://creativecommons.org/licenses/by-nc-sa/3.0/