Biotechnology and its Applications Test - 10

Many transgenic animals are used to increase our understanding of how genes contribute to the development of disease. The animals are genetically engineered to produce the disease symptoms so new and effective treatments can be studied. Today transgenic models exist for many human diseases such as cancer, cystic fibrosis, rheumatoid arthritis and Alzheimer’s disease.

In 1997, the first transgenic cow, Rosie, produced human protein-enriched milk at 2.4 grams per litre. This transgenic milk is a more nutritionally balanced product than natural bovine milk and could be given to babies or the elderly with special nutritional or digestive needs. Rosie’s milk contains the human gene alpha-lactalbumin.

Transgenic mice are developed for use in testing the safety of vaccine before use on human beings. Polio vaccine was first tested on mice for its safety before use on humans.

The majority of transgenic animals produced so far are mice, the animal that pioneered the technology. The first successful transgenic animal was a mouse. A few years later, it was followed by rabbits, pigs, sheep, and cattle.

Transgenic mice, rabbit, pigs, sheep, cows etc. have been produced but more than 95% of them are mice.

Some transgenic animals are produced for specific economic traits. Transgenic animals can used to produce useful products by Introduction of portion of DNA which code for particular product.

For example, transgenic cattle were created to produce milk containing particular human proteins, which may help in the treatment of human emphysema.

Transgenic model for treatment of disease is available today for cancer, cystic fibrosis, Alzheimer’s disease and rheumatoid arthritis disease.

Transgenic animals can be specifically designed to allow the study of how genes are regulated, and how they affect the normal functions of the body and its development, e.g., study of complex factors involved in growth such as insulin-like growth factor. By introducing genes from other species that alter the formation of this factor and studying the biological effects that result, information is obtained about the biological role of the factor in the body.

Chemical safety testing: This is known as toxicity/safety testing. The procedure is the same as that used for testing toxicity of drugs. Transgenic animals are made that carry genes which make them more sensitive to toxic substances than non-transgenic animals. They are then exposed to the toxic substances and the effects studied. Toxicity testing in such animals will allow us to obtain results in less time.

Transgenic animals are used to study the toxicity effects of certain chemical in which animals are made to carry gene which make them more sensitive to toxic substance and exposed to toxic substance to be studied.

Medicines required to treat certain human diseases can contain biological products. Transgenic animals that produce useful biological products can be created by the introduction of the portion of DNA (or genes) which codes for a particular product such as human protein (α-1-antitrypsin) used to treat emphysema. Similar attempts are being made for treatment of phenylketonuria (PKU) and cystic fibrosis. In 1997, the first transgenic cow, Rosie, produced human protein-enriched milk (2.4 grams per litre). The milk contained the human alpha-lactalbumin and was nutritionally a more balanced product for human babies than natural cow-milk.