It was a shock. In November 2018, a carefully secret report leaked to global media that twins had been born in China, to which biophysicist Jiankui He and his team had deliberately adjusted the hereditary information. He used a technology called CRISPR-Cas9, which allows targeted intervention on hereditary information.
For this experiment, he obtained couples where the partner was HIV positive and the partner was not infected with HIV. These people can produce a child without risk of infection by fertilizing in a test tube, where the HIV virus is removed from their father’s semen.
But in China, this procedure is prohibited. He promised his parents that he would arrange for them to give birth in a test tube, and that he would also experiment with an “HIV vaccine”. In fact, when it was fertilized in a test tube, it manipulated the hereditary information of the resulting embryos.
He and his colleagues have used the technique known as intracytoplasmic sperm injection to conceive children, in which the father’s sperm is injected directly into the egg under a microscope using special tools and devices. Along with sperm, He et al. CRISPR-Cas9 molecules targeting the CCR5 gene in the egg. The goal was to damage this gene.
He was inspired by the well-known fact that some people in northern Europe have the CCR5 gene damaged by a mutation in which thirty-two letters of the genetic code fell out of the gene at a very specific location. The HIV1 virus binds to the protein encoded by the CCR5 gene on the surface of white blood cells, and if a person has inherited a CCR5 gene mutation called “delta 32” from both parents, they are resistant to the HIV1 virus. The virus does not attach to his blood cells.
However, in the Chinese team’s experiment, CRISPR-Cas9 was not designed to induce a “delta 32” mutation in the embryo’s hereditary information. CRISPR-Cas9 only made “holes” of different sizes in the gene, and in the case of an embryo, it didn’t even damage the gene in all the cells of the developing embryo.
The girls born from these embryos, referred to in the media by the fictitious names Nana and Lulu, therefore do not have a total guarantee of resistance to HIV1, and Lulu even has the certainty that cells with a functional CCR5 gene continue to be present in it. body. It is therefore susceptible to HIV1 infection. A little later, a second experience was to give birth to a boy. We don’t know anything more about him.
The world has condemned Jiankui He’s actions as totally irresponsible. In similar experiments, CRISPR-Cas9 can damage other DNA sites, causing unwanted side effects. Although Jiankui He claimed that testing the children’s hereditary information did not confirm such an error, experts agree that the analyzes performed were not sufficient to rule out DNA damage.
Jiankui He was guilty under Chinese law and given a three-year suspended prison sentence. Two out of ten of his colleagues were also sanctioned.
What about enhanced children?
The three children with “improved” heredity are the first people targeted in the hereditary information by transmitting the change to their descendants.
Nothing more is known about their fate. According to the scientific journal Nature, two Chinese bioethics have now produced materials, which they have distributed to Chinese ministries of health, education and science and industry.
Renzong Qiu of the Chinese Academy of Social Sciences in Beijing and Ruipeng Liu of Central China University in Wuchan point out that children born from Jiankui He’s experiments are “vulnerable”.
It is therefore necessary to provide comprehensive support. For example, children should have double-checked hereditary information. At the same time, they should be provided with comprehensive medical care.
Jinakui He and the university where he was working at the time of the experiment, as well as the Chinese state, should bear some responsibility for it. They should share the financial costs associated with this care.
If these adult children decide to start a family, they must be conceived by fertilization in a test tube and the hereditary information of the resulting embryos must be carefully checked. Offspring should only be born from embryos guaranteed to be DNA-free.
The document has been reviewed by selected foreign experts and is also available to the editors of Nature magazine. It is foreign experts who disagree on the approach proposed by Chinese bioethics. On the one hand, they welcome the fact that the issue of children from irresponsible experiences is addressed.
“It’s an important document,” says geneticist Gaetan Burgio of the Australian National University in Canberra, according to a report by Lei and Qiu.
But Joy Zhang of the University of Kent in Canterbury, England, argues that it is difficult to come up with measures for children born from experiences that no one knows anything about.
“China keeps everything a secret,” Zhang complains.
Eben Kirksey of the Alfred Deakin Institute in Melbourne, Australia, agrees that children should receive the necessary care, but disagrees with the extent suggested by Qiu and Lei. According to him, less will bring more. Excessive care can bring unwanted attention to children and turn their lives into hell.
“Increased attention can lead to increased vulnerability in children,” warns Kirksey.
Zhang agrees, fearing the children will face social stigma for the rest of their lives.
“By handing them over to a select group of people, we won’t help them in any way, but we will make their situation even worse,” Zhang said.
In this context, Kirksey recalls the case of Louisa Brown, who was born in 1978 as the first child of a zeb tube. She underwent all kinds of medical tests.
“But in the long run, it was the hardest thing for her to maintain a normal life after becoming a public figure,” says Eben Kirksey.
Will there be more upgraded children?
The urgency of addressing the issue of children with altered hereditary information underscores the suspicion that the three Chinese children are not alone.
‘Certainly not the last,’ says Danish anthropologist Ayo Wahlberg of the University of Copenhagen of the three Chinese children with altered DNA
Qiu rules out that other children are born directly in China. According to him, punishing Jiankui He was sufficient warning for all Chinese scientists.
“No Chinese scientist would dare to break the rules now,” Qiu said.
Photo: NIH Image Gallery, CC HTTPS://CREATIVECOMMONS.ORG/PUBLICDOMAIN/MARK/1.0/ https://creativecommons.org/publicdomain/mark/1.0/
But there are scientists in the world who do not hide their intention to give birth to children with targeted hereditary information. These include, for example, Russian geneticist Denis Rebrikov from the Kulakov Medical Center in Moscow.
He has already announced a study in which he proposes to deaf parents carrying a damaged GJB2 gene that once fertilized in a test tube, he will repair the embryos so that they can give birth to hearing-impaired children. He has not yet recruited the volunteers needed for his project.
“But I’m sure that one day we will have volunteers who want a hearing child to be born,” Rebrikov said.
Of course, it cannot be ruled out that other scientists have conducted, are conducting and will conduct similar experiments without making this known to the public. No one will stop making people better anymore. But it can’t be “dropping the chain”. In this, the material of Chinese bioethics is a step in the right direction.