What is a Rosie?

The correct answer is A transgenic cow.

Key Points

• Organisms that have altered genomes through artificial means are known as transgenic.
• The first transgenic cow was Rosie and was produced in 1997.
  • It consists of the human alpha-lactalbumin gene.
  • Its milk contained 2.4gms of human α-lactalbumin per litre of milk.
  • It produces human protein-enriched milk, which was a nutritionally more balanced product for human babies than natural cow milk as it contains 'human alpha-lactalbumin'.

Additional Information

Reasons for production of transgenic animals:

• Study of Physiology & Development -
  • Study of how genes and their regulation affects the physiological functioning of the body.
  • Complex growth factors like insulin can be studied.
• Study of Diseases -
  • Transgenic animals serve as model organisms for studying human diseases.
  • They help in understanding the disease development process from genes.
  • They are also used for investigating new treatment methods.
  • Transgenic models exist for diseases like cancer, cystic fibrosis, rheumatoid arthritis and Alzheimer's.
• Biological Products -
  • Many biological products that are essential for formulating medicines of use are often expensive.
  • These products can be obtained easily from transgenic animals.
  • This can be achieved by just introducing the gene responsible for the desired product into a suitable organism.
  • Example - Alpha-1 antitrypsin is a human protein that is required for emphysema treatment.
• Vaccine Safety -
  • Transgenic mice can be used to test safety of vaccines before using for humans.
• Toxicity Testing -
  • Transgenic animals can be made more sensitive to certain chemicals or drugs.
  • These animals are exposed to the toxic substances and their effects are then studied.