For as long as humans have conceived of making hybrid organisms, an ethical debate has been waged over whether or not we should. The pros and cons are vast and poignant. Each new scientific advancement towards making hybrids stokes the fire of controversy. This year, researchers presented work at a conference detailing the most recent hybrid: a sheep-human chimera.
To create these chimeras, scientists used CRISPR to disable the genetic pathway for specific organs, like the heart and liver, so they wouldn’t develop. Next, the sheep embryos were injected with human undifferentiated cells which started specializing to form the missing organs. The goal of this research is to grow human organs for medical purposes, such as organ transplants. However, only about 1 in 10,000 cells in this sheep embryo were human. The ratio would need to be closer to 1% before the organs could be viable. Despite that, this event marks an important milestone: it is plausible to grow human organs in a non-human organism. This work is also being duplicated with pigs.
In a world that is currently experiencing an organ shortage, where 20 people die each day waiting for an organ, this controversial research might provide a solution. The ethical debate concerning organ farming has started and will only grow in fervor. However, if we want to solve this organ crisis, we should be careful about banning promising and regulated too soon. It is possible this work is only a stepping stone to growing organs in a lab without any animal host at all. Would it be okay then?
Managing Correspondent: Zane Wolf
Original Abstract: Towards Xenogeneic Generation of Human Organs – AAAS 2018
Media Coverage: Scientists Just Made Sheep-Human Hybrids. Here’s What You Need to Know – ScienceAlert; Sheep-Human Hybrids Made in Lab – Get the Facts – NatGeo; Breakthrough as scientists grow sheep embryos containing human cells – The Guardian
Related SITN Articles: The End of the Waitlist: How chimeras could solve the organ transplant problem; Beyond mythology: NIH plans to lift ban on chimera research; How we talk about science matters: A bioethicist’s view on controversial research and science policy
Image Credit: Juan Carlos Izpisua Belmonte