- Researchers mix human cells into monkey embryos.
- The aim is to convert animals of other species into factories of organs for transplants.
- The research was carried out in China to escape European laws.
In recent years, the combination of two major themes of biology — stem cells and genome editing — has opened new avenues for biomedical research.
It is now possible to grow tissues and organs of some species within an organism of a different species. These advancements offer a great opportunity to tackle human health problems and long-standing scientific mysteries. However, many believe that crossing the species barrier could be very harmful in the near future.
Recently, a team of Spanish and American scientists took a big controversial leap by mixing human cells into monkey embryos. They carried out this research in China to escape European laws.
The research team led by the Spanish-born biologist Juan Carlos Izpisúa has managed to develop for the first time chimeras of human and monkey. They have successfully injected embryonic stem cells into a days-old embryo of monkey.
The aim is to convert animals of other species into factories of organs for transplants. These organs, including liver and kidney, would be made up entirely of human cells.
What exactly is a chimera?
As per Greek mythology, a chimera is a monster with a goat belly and dragon tail, capable of breathing fire through the jaws of its lion’s head. Scientific chimeras are, however, less fancy.
The one being studied has genetically altered monkey embryos. Researchers used advanced gene-editing technology to disable certain types of genes in monkey and injected human cells capable of producing any type of tissue.
Source: El País, the Spanish daily newspaper
To be clear, no human-monkey hybrid has been born yet. Instead, they mixed embryos and allowed it to develop for only a couple of week. The embryos were studied carefully during this period and results seem quite promising. However, researchers did not share any details. They were waiting for their paper to be published.
This is not the first time they are making human-animal chimeras. In 2017, they tried to create chimeras by adding human cells to pig embryos but it didn’t work out well. Humans cells contributed very little to the development of the embryo.
Since humans are genetically closer to monkeys, researchers chose to perform such experiments on monkeys. The current gene-editing technology also increases the chance of human cells to grow along with the monkey embryos.
The research is extremely controversial. In the United States, the National Institutes of Health does not allow biomedical and public health research centers to mix human-money embryos. However, there are no such regulations in China, which is why the study is going on there. It is funded by the Catholic University of Murcia, a private university in Spain.
Some scientists are raising questions about ethical barriers. If nature knows how to do certain things, why humans have to do them in a lab? We must be cautious with any genetic alterations that can be transmitted to our offspring.
Izpisúa, on the other hand, says “History shows us again and again that, over time, our ethical and moral scales change and mutate, like our DNA”.