And how would you like your eggs? Pharmaceutical-side up?
This may soon become a reality as scientists develop genetically engineered chickens that produce pharmaceutically beneficial proteins in their eggs. Instead of going to the doctor with an ailment, you can enjoy your favourite fried eggs without any guilt as they cure your illness.
But why choose chickens? Chickens can reproduce in a short period of time, with a generation time of five to six months, making the process quick and cheap. Also, hens produce around 330 eggs a year, each containing a large quantity of protein that can be farmed for pharmaceutical needs. Finally, proteins are deposited only in the egg white which is a biochemically simple compound. This makes protein removal easy as there are already established methods for this form of extraction.
Recently, scientists have produced chickens that pass injected genes on to their progeny that remain viable in each animal for up to sixteen months and remain active for four generations. However, there are still several hurdles to be overcome before commercial production begins. Firstly, scientists need to efficiently remove embryos from hens and provide an environment for normal development before they are injected with the foreign DNA. Next, mariner, a recently discovered genetic element, must be further developed as an agent to insert specific genes into chicken chromosomes. Finally, methods must be developed to increase concentrations of foreign proteins in egg whites to make the project commercially viable. However, the big issue will be ethical dilemmas associated with genetically modifying animals for human benefits.
By Danielle Appay
Student No: 41444102
Primary Reference: Pickerell, John 2002, 'Scrambled Drugs: Transgenic chickens could lay golden eggs', Science News, vol. 161, no. 14, pp. 213.
See also: Wayman, Erin 2007, 'Barnyard Pharmaceuticals', ScienceNOW, viewed 28 May 2007, http://sciencenow.sciencemag.org/cgi/content/full/2007/116/4
Union of Concerned Scientists 1998, 'Genetically Engineered Chickens', The Gene Exchange, viewed 28 May 2007, http://go.ucsusa.org/publications/gene_exchange.cfm?publicationID=271
