Scientists at the University of California, Davis are trying to harvest human organs inside pigs. Despite it being a controversial plan, this could one day solve the worldwide shortage of transplant organs.

Apparently, they already injected human stem cells into pig embryos, which were allowed to grow for 28 days before terminating it for tissue analysis. However, if a chimeric embryo was allowed to grow full-term and be born, it would have looked and acted like a regular pig except it would have developed human internal organs.

The experiment involved employing CRISPR, a gene-editing technique. Through this method, a portion of the pig’s DNA needed for the embryo to develop pancreas was injected with human induced pluripotent (iPS) stem cells, which are cells that have the capacity to grow into any type of tissue.

human organs

Scientists are trying to harvest human organs in pigs. Credit: Tufts Medical Center

The team hopes that tissue analysis results will confirm that the pancreas is compatible for human transplant. Once confirmed, this would mean that other similar animals could also serve as sources for human organs.

However, the US National Institutes of Health did not welcome the idea of creating pigs with human organs. Authorities were concerned that the human cells could make the animal’s brain and behavior more human. But according to lead researcher and reproductive biologist Pablo Ross, creating pigs with human brains is highly unlikely. Nevertheless, Ross told BBC that they will study this concern further.

Others have also feared that animal organs could be infected with animal viruses that will harm the human patient. On the contrary, Harvard Medical School showed that the CRISPR technology can also be used to prevent virus transmission after successfully removing over 60 retrovirus genes in pigs in 2015.

Geneticist Robin Lovell-Badge from the Francis Crick Institute in London pointed out that the new technique could face some serious challenges. Other animal cells present in the organs or the human cells undergoing modification inside the pig embryo could make these organs incompatible with human patients.