Imagine a world where scientists experiment with the genes of human embryos, turning them on and off to see what happens.
It sounds like something straight out of a science-fiction movie, but that’s exactly what scientists are doing right now. Using a “genome editing tool” called CRISPR/Cas9, British researchers have successfully changed the DNA of human embryos to study the effects of certain genes on human development.
"One way to find out what a gene does in the developing embryo is to see what happens when it isn't working," said Kathy Niakan, a stem cell scientist who led the research at Britain's Francis Crick Institute.
Niakan’s team decided to use it to stop a key gene from producing a protein called OCT4, which normally becomes active in the first few days of human embryo development.
They spent more than a year optimizing their various techniques using mouse embryos and human embryonic stem cells in lab dishes, before starting work on human embryos.
To inactivate OCT4, they used CRISPR/Cas9 to change the DNA of 41 human embryos. After seven days, embryo development was stopped and the embryos were analyzed.
To be clear, for those that believe life begins at conception, “embryo development was stopped” means a life was ended. The scientists discovered that the gene that produces the OCT4 protein is necessary to the embryo’s growth.
After an egg is fertilized, it divides until at about seven days it forms a ball of around 200 cells called a blastocyst, Niakan explained in a briefing about her work.
Her results, published in the journal Nature on Wednesday, found that human embryos need OCT4 to form a blastocyst. Without it, the blastocyst cannot form or develop normally.
The scientists involved in this research believe their technique could be used to cure genetic mutations in embryo development and help improve IVF treatments for infertile couples. Weeks ago, another team of scientists reportedly edited the DNA in human embryos to cure a genetic defect that caused a heart disorder.
But critics argue it is an immoral practice and fear this new technology could be used to create babies to market-order.
Marcy Darnovsky, the head of the Center for Genetics and Society, a genetics watchdog group, told NPR, "The concerns are that we would be opening the door to fertility clinics vying to offer gene-editing to make future children taller or stronger or whatever they wanted to market."
"That could put us into a situation where some children were perceived to be biologically superior to other children,” she said.
The stem cell scientists, however, say that genes of animal embryos operate differently from those of human embryos, and are thus insufficient.
"This is opening up the possibility of using a really powerful, precise genetics tool to understand gene function," Niakan said. "We would have never gained this insight had we not really studied the function of this gene in human embryos."
While there are benefits to this research, there are profound ethical questions surrounding the morality of "editing" human embryos. If life begins at conception (as many believe), these scientists are experimenting with human lives. Each embryo that fails to develop — or is discarded after the experiment — dies. If life doesn’t begin at conception, where is the line drawn?
Why is an embryo that’s a few days old not a life, but a fetus at six months is? Is it moral or ethical then to experiment on a human fetus that is further along in development before birth?
It is difficult to see how this radical development in science can be consistent with the wide understanding and belief that the subjects of these experiments are precious human life.