By Swain Thorne
We now have the technology to alter genes in embryos. We can implant the altered embryos into women’s uteruses, and the women will give birth to genetically-engineered babies. In fact, it’s already been done, in a rogue experiment in China.
Scientist He Jiankui announced in 2018 that he had used CRISPR gene editing to change embryonic DNA in the lab, using in-vitro-fertilized embryos, and he implanted the altered embryos into the womb of a study participant. She gave birth to two genetically altered twin girls. A year later, another study participant gave birth to a third girl whose DNA had also been altered in the lab.
In December 2019, He Jiankui was convicted in China of violating medical regulations and sentenced to three years in prison. He was released sometime before April 4, 2022.
Why is embryo editing controversial?
Embryo editing is done right after fertilization, when the embryo is still a single cell. As the cell continues to divide and redivide, the altered DNA is carried into every cell of the developing body. The sperm or egg cells will also have the altered DNA and will carry the genetic changes down to future generations.
One problem is that CRISPR gene editing is not perfect. The process involves an enzyme, Cas-9, that cuts apart the DNA at what is supposed to be a precisely chosen location on the genome. However, it doesn’t always work the way it should, and the enzyme sometimes makes the cut in the wrong place. And sometimes the cell’s natural repair mechanisms damage the DNA adjacent to the cut.
A CRISPR error will cause unintended and unpredictable changes to the genome. If the error occurs while scientists are altering the DNA in an embryo, there may be serious consequences that could be inherited in future generations. For this reason, many scientists believe that creating a gene-altered baby should be off-limits until we are able to perform gene editing more reliably.
Another ethical dilemma is whether gene editing should ever be allowed for making “designer babies.” Should parents be able to boost their offspring’s IQ or choose their eye color? Even He Jiankui believes this should not be done.
He Jiankui, however, defends his experiment. He says he was not trying to create designer babies. Instead, his modification involved changing a gene to make the babies, whose fathers were all HIV-positive, resistant to HIV.
What are the ethical implications of CRISPR embryo editing?
CRISPR embryo editing gives scientists unprecedented power over human evolution. While there is strong support in the scientific community for using gene editing after birth to fix mutations that cause disease, there is widespread condemnation for making genetic alterations, as He Jiankui has done, that will cause heritable changes.
We don’t know the effect that heritable alterations could have on our species in either the short or the long term, especially when the CRISPR gene editing process is as error-prone as it is now.
The prospect of creating “designer babies” raises many ethical questions. Who gets to choose the traits of their offspring? Could this technology ultimately be used by a ruling power to create a “Brave New World” scenario where humanity is remolded to fit the needs of those who are in control?
For now, ethicists are urging that we go slow and have more discussions. Society as a whole needs to work out how it feels about embryonic gene editing before we try to put it into practice.
What does the future of this practice look like?
For now, it looks like the creation of gene-alerted babies has stopped. He Jiankui’s arrest and imprisonment put a damper on other Chinese efforts to do similar work. The practice remains illegal in the United States and much of Europe.
But the cat is out of the bag. Work continues on embryonic gene alterations in the lab. Although these embryos are not being implanted now, it’s probably only a matter of time before another scientist performs another rogue experiment, and more gene-altered babies will be born.
Over the longer term, perhaps the development of more reliable genetic editing techniques will make the creation of gene-altered babies safer and more predictable – although the potential for abuse may never go away.
