For the first time, human cells have been injected into pig embryos and grown for four weeks, a precursor to eventually attempting to grow human organs inside pigs or other animals.
The human cells comprised only a tiny part of each pig embryo, about one in 100,000 cells, The Associated Press reported. After a few weeks, the embryos were removed for study.
Although the U.S. government has not funded human-animal genetic research since 2015, the new work done in California and Spain was privately funded, the AP said.
Scientists are still “far away” from being able to grow human organs in pigs, study author Juan Carlos Izpisua Belmonte said, the AP reported. The new research is “just a very early step toward the goal.”
Eventually, though, chimeras, or human/animal hybrids, may be able to ease the organ shortage and save the lives of people waiting organ donor lists. By using stem cells from the person who needs the transplant, the chances of organs being rejected are greatly lowered as well, National Geographic reported.
Stem cells theoretically have the ability to grow into any organ in the body, but increasingly specialized procedures have been needed to make the cells grow into particular organs.
The research on human cells in pig embryos is not without conflict. Many people have ethical problems with using animals to grow and harvest human organs as well as creating embryos in a lab that will later be euthanized, the AP reported. Others look forward to the many lives that could be saved if organs can be grown from stem cells and harvested for those who need them.
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