The Chimera, a cornerstone of Greek mythology, may turn from fiction to fact in this lifetime. A team of researchers at the University of California, Davis is attempting to create a human-pig hybrid for the purpose of growing and transplanting organs into sick patients, the BBC reports.
According to the U.S. Department of Health and Human Services, an average of 22 Americans die every day waiting for an organ donation. The demand for this kind of organ-genesis for transplant research is high, but how exactly can human organs grow inside the body of a pig?
The UC Davis Researchers are attempting to do this by splicing the DNA of pig embryos with human induced pluripotent stem cells (iPS).
In general, all stem cells have an inherent ability to differentiate into other specialized cells, such as skin, bone or muscle and can transform into almost any type of tissue.
The research team is currently attempting to grow a pancreas inside the body of a pig using these iPS cells. They will do this by taking a pregnant sow and removing one of the embryos. Next they plan to delete the section of the embryo’s DNA that would normally be programmed to help grow a pancreas. Then they will inject the embryo with human iPS cells programmed to grow into a pancreas.
The hope is that the iPS cells will fill the gap in the pig’s DNA and allow it to grow a human pancreas, instead of a pig pancreas. The embryo will be implanted back into the sow to incubate for 28 days before removal for study. The researchers expect the pigs to be unaffected by the splice and growth of human organs inside the embryo.
Pablo Ross, leading researcher on the project, told the BBC that the team hopes the “pig embryo will develop normally but the pancreas will be made almost exclusively out of human cells and could be compatible with a patient for transplantation.”
If the research is successful, it is possible that eventually, the iPS cells of a sick patient in need of a new organ, like a liver, could be injected into a pig embryo. The liver growing inside the pig embryo “would be an exact genetic copy of your liver but a much younger and healthier version and you would not need to take immunosuppressive drugs which carry side-effects,” Ross told the BBC.
While this is a potentially life-saving solution, it does not come without an ethical price-tag.
Ethical concerns center on the possibility that this type of research may be intentionally abused for genetic engineering. Even if this research is not abused, it may result in unintentional consequences and externalities. The BBC has cited one possibility of pigs becoming “more human” as a result of splicing human and pig DNA together.
The NIH issued a statement in September 2015 for exactly that reason, declaring that it would halt all funding for this genre of research.