Chickens Cracking the Code

Chickens have been identified as a possible viable source of pharmaceuticals that could be used to treat a number of human diseases and conditions. Genes that encode certain proteins in chickens can be modified so they encode different proteins that are used in human medicine. Their high protein content makes chicken eggs ideal for this purpose as only a small amount of the modified protein would need to be produced per egg to make it economically viable. Once the protein is produced the relative simplicity of albumen (egg white) should make it easy to isolate it. Although these genetically modified chickens would have great potential researchers have had difficulty finding an efficient method of actually modifying them.
The most common method used in the modification of mammals has posed some problems when applied to birds. This method involves injecting DNA into a newly fertilised egg and in a chicken this egg is both fragile and difficult to obtain soon enough after fertilisation. Some progress has been made using a modified form of a virus to change the genomes so that they can encode the new protein. However this method produced a relatively low percentage of male offspring and therefore had limited potential for mass production.
So although chickens have great potential to provide therapeutic proteins for human use, an efficient and reliable method of modification is yet to be developed.
Primary reference:
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T64-4FFMXS0-B&_user=331728&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000016898&_version=1&_urlVersion=0&_userid=331728&md5=463d057d3829e20e2e474d099e4c6c37
Some interesting articles:
http://www.poulvet.com/poultry/articles/3.php
http://www.detnews.com/2005/business/0503/20/C06-122188.htm