“Scientists have begun blurring the line between human and animal by producing chimeras—a hybrid creature that's part human, part animal.”
Mary Ann Mott, National Geographic News
According to Reuters UK ( “Factbox: Human Fertilisation and Embryology Bill” ), controversial medical research innovations are being debated in Parliament’s House of Commons this week. The Human Fertilisation and Embryology Bill raises several interesting bioethical issues, one of which would allow the creation of human-animal hybrid embryos to be used for medical research.
Interspecies embryos would be created by taking a cell from a patient and inserting it into an enucleated animal ovum. An electric shock would fuse the two cells together allowing the formation of an embryo. Because the genetic material from the animal has been removed, the resulting embryo would be 99.9% human and an excellent model for medical research. The proposed legislation mandates that these embryos must be destroyed before 15 days, and they must not be implanted into the uterus of a woman or another animal.
The advantage of creating mixed-species embryos is that they can be a powerful research tool for developing stem cell models without the use of human eggs. Embryonic stem cells would be taken from the new hybrid embryo and injected into specialized human tissues, giving researchers insight on understanding the progression and possible treatment of medical conditions such as Alzheimer's disease, cystic fibrosis, Parkinson’s disease, diabetes, and other inheritable diseases. Stem cells could also be used to repair human tissue by allowing new tissue that is genetically matched to the individual to be cultivated for damaged body parts without the risk of rejection.
Scientists and researchers are excited about the medical possibilities that may unfold, and supporters of this bill are convinced that these techniques are “an inherently moral endeavor” that could eventually save millions of lives. There is, however, a great deal of public anxiety about the ethics of experimenting across species boundaries. Many critics find it unnatural and morally wrong to combine human and animal genetics. They also question the benefits of hybridization, claiming that there is no evidence that this will help cure diseases and that other research methods are more effective. They find it both misleading to the public and an abomination to nature. “There are other ways to advance medicine besides going into the strange, brave new world of chimeric animals.”
Even scientists are divided on this issue. Although there may seem to be medical advances to be gained from human-animal hybridization, we really need to make sure that these benefits outweigh the possible risks. In the words of William Cheshire, associate professor of neurology at the Mayo Clinic’s Jacksonville, Florida branch,
“We must be cautious not to violate the integrity of humanity or of animal life over which we have a stewardship responsibility. Research projects that create human-animal chimeras risk disturbing fragile ecosystems, endanger health, and affront species integrity.”
[Photo courtesy of goatboyfilms.com/.]