BY: CAROLINE ROLF
Known to science as chimeras – lab created embryos that are part human, part pig – could be a sustainable method of growing and harvesting transplant organs for patients in need. The ultimate goal is a future where new, young, healthy organs are ready on demand, eliminating long wait lists for a new liver, heart or kidney.
Researchers at the University of California removed the small portion of a pig’s DNA that would form a pancreas, replacing it with the human cells required for the same organ. The hybrid of human stem cells and pig DNA develop for 28 days in sows before the pregnancies are terminated and removed for tissue analysis. They believe that if the animals had been carried to term they would have fully developed the human organ but otherwise been a normal and healthy pig.
Such work is controversial for those who think there could be serious practical and ethical consequences if humans and animals are combined. Have tests been run to see how human genes affect other parts of the pig’s body, such as the brain? The National Institutes of Health claimed it would not back the research funding until it knew more about the implications. If everything does go according to plan, the team believes the pig will live a normal life, unaware of the human organ inside its body. However, at this early stage, it’s unclear if a genetically altered pig will thrive until one is born and studied.
“It is also possible that the surface of the human cells may be modified inside the pig embryo, potentially leading to the organ being rejected by a human,” geneticist Robin Lovell-Badge tells The Guardian.
No matter the outcome of this experiment, human organs will remain in high demand. Over 120,000 people are currently on the wait list for transplants in the U.S. While using animals to grow human organs is a unique answer to the world’s donor shortage, it’s also something we need to take at a slow and careful pace—just because we can do something about it, should we?
Image sourcing: summertimestock.com, bbc.com
