Monday, April 17, 2006

Is this cow a human-animal hybrid?

In his 2006 State of the Union address President Bush slipped in a call for a ban on "human-animal hybrids." It's probably a phrase that brings thoughts of centaurs, fauns and harpies to some minds.
But, despite the President's stern disapproval of mixed-species clones, we may soon find food products derived from them not just in our research labs, but on our kitchen tables within the next year.
A Dutch biotechnology company called Pharming
has genetically engineered cows, outfitting females with a human gene that causes them to express high levels of the protein human lactoferrin in their milk. According to Pharming's website, the proteinwhich is naturally present in human tears, lung secretions, milk and other bodily fluidsfights against the bacteria that causes eye and lung infections, plays a key role in the immune system of infants and adults and improves intestinal microbial balance, promoting the health of the gastro-intestinal tract.
Scientists have tested the toxicity of the proteinisolated from the cows' milkon rats. They found thateven at the high level of 2,000 mg recombinant human lactoferrin per kg body weightorally consumed human lactoferrin has no adverse effects to complement all the supposed benefits already mentioned.
Pharming has, therefore, filed a notification with the FDA asking that their lactoferrin be labeled "Generally Recognized As Safe" (GRAS). If the FDA approves this product, human lactoferrin derived from these cloned cows could be in America's yogurt, popsicles, sports drinks and snack bars within months.
To create human lactoferrin-lactating cows, Pharming's scientists introduce human DNA coding for the protein's production into the nuclei of fertilized bovine eggs. The cells that successfully incorporate the foreign DNA or "transgene" are then selected, and each is fused with a second egg cell that has had its nucleus removed. The fused cells are then implanted in a surrogate cow's uterus. If all goes well, the cow becomes pregnant with a transgenic calf that, upon maturity two years later, will produce milk containing human lactoferrin. Despite that one component of its milk, the calf is all bovinebut technically remains an example of the dastardly human-animal hybrid.
The "humanness" of the protein may be both its strongest selling point and the label that will delay and possibly squash its eventual release to the marketplace. Surveys consistently show that Americans are wary of using genetically modified animals, specifically cloned animals, for food. In fact, a 2005 survey by the Pew Initiative On Food And Biotechnology
found that only 23% of American consumers believe that food from cloned animals is safe, while 43% believe it is unsafe.
Despite the public sentiment, the FDA is still working out its official policy on transgenic animals. The agency currently asks that any company looking to introduce transgenic animals into the food supply contact the Center for Veterinary Medicine for instructions on how to prepare an investigational file. It has not yet approved any food from transgenic animals, but according to Singh, the organization has approved a handful proteins made through mammalian cell culture technology, where cells are cultured in a synthetic environment.

"The Federal policy on transgenic animals is under discussion at the White House level," said an FDA spokesperson via e-mail. "Those discussions will ultimately produce a seamless interagency approach to the regulation of genetically engineered animals."
Products from transgenic animals have seen no real success in passing through any approval agencies, thus far. According to the BBC, in February, the European Medicines Agency turned down an application to license Atryn, an anti-clotting agent collected from the milk of transgenic goats, because of insufficient scientific research into its safety and benefit. California-based Ventria Bioscience filed a GRAS notification on human lactoferrin produced in rice back in December, 2004. The status of the application is still listed as pending—every other notification from 2004 was closed by mid-2005. Singh isn't worried that his human lactoferrin protein will face a similar fate.
"Regulatory agencies both in the US and Europe have not said to companies who are working with this sort of technology that they have any issues with the technology itself," Singh said. "There are different uses and different applications; I think this is a relatively straightforward application. If there aren't any issues with the protein itself, I would expect the regulatory agencies would not have any serious concerns."
As for the President's State of the Union remarks, the FDA had no comment. Singh said he'd received feedback from others in the biotechnology industry that Bush was not talking about these sort of transgenic animals but rather about animals created purely for human organ harvesting, such as mice capable of growing human ears on their backs.
Even though Pharming has run multiple tests on their protein to ensure it is safe, and the FDA's claims that it's open to transgenic technology, human lactoferrin from transgenic cows faces an uphill climb from the lab in the Netherlands to the shelves at your local grocery store. The people at Pharming are just hoping that regulatory agencies recognize that transgenic milk does a body good. Very good.

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