Transgenic Animals

Rosie, a transgenic cow created in 1997, produced human protein-enriched milk that contained human alpha-lactalbumin, a fact stated in NCERT Class 12, Chapter 11 (Biotechnology and its Applications). The milk yielded about 2.4 grams of this protein per litre, making it more balanced and nutritionally suitable for human infants than ordinary cow milk. This was achieved by introducing the human gene for alpha-lactalbumin into the animal, demonstrating how transgenic animals can serve as living factories for valuable human proteins. Casein is the major natural protein of milk but it is not the human protein that Rosie was engineered to produce. Keratin is a structural protein of hair, nails and skin and has no relevance to milk enrichment. Collagen is a connective-tissue protein found in skin and bones, again unrelated to this experiment. Such transgenic animals are valued because they can secrete a desired human protein in large, easily harvested quantities through their milk, a strategy sometimes called molecular pharming. A consistency check supports the answer: the goal was to make cow milk more like human milk for infant nutrition, and alpha-lactalbumin is the human milk protein specifically named in this transgenic achievement.