Write any two scientific and commercial values of transenic animals in favour of human beings .

Explanation

Transgenic animals are used for the following purposes:
1. Study of diseases: With the help of transgenic animals, investigation and new treatments for human diseases can be found out. Cancer, cystic fibrosis, rheumatoid arthritis and Alzheimer's disease have been studied with the help of transgenic animals. Some transgenic animals are designed to study how genes contribute to the development of disease.
2. Vaccine safety: With the help of transgenic mice safety of polio vaccine is tested.
3. BIoreactors: Transgenic animals are used as bioreactors. Pharmacologically important proteins such as `alpha`- 1-antitrypsin is produced in the transgenic animals. This protein is used in the treatment of emphysema. For treatment of phenylketonuria (PKU) similar attempts have been made. Rosie, the first transgenic cow has produced human protein enriched milk which as nutritionally more balanced than cow's milk.
4. Chemical safety testing: Toxicity testing is doe on transgenic animals to obtain results rapidly. Transgeic animals possess genes which make them more sensitive to toxins.