What are transgenic animals? Explain any four uses of transgenic animals, with examples.

1. 1 · Define in one line. Transgenic animals have DNA manipulated to possess and express an extra (foreign) gene.
2. 2 · Give examples. Rats, rabbits, pigs, sheep, cows and fish; over 95% are mice.
3. 3 · Explain the uses.
   • Normal physiology: e.g. insulin-like growth factor.
   • Disease models: cancer, cystic fibrosis, rheumatoid arthritis, Alzheimer's.
   • Biological products: α-1-antitrypsin for emphysema; Rosie's milk with alpha-lactalbumin.
   • Vaccine safety: polio vaccine tested on transgenic mice.
   • Chemical safety: animals more sensitive to toxins give faster results.
4. 4 · Describe Rosie. First transgenic cow (1997); 2.4 g per litre of human protein; milk better balanced for human babies.
5. 5 · Link to real life. Safety testing on transgenic mice helps bring safer vaccines and medicines to India.
6. 6 · Close in one line. So transgenic animals help research, medicine and safety testing.

Scoring tip: Give one named example for each use; Rosie and α-1-antitrypsin are the most asked.