MOSCOW, April 14, Tatyana Pichugina Chinese scientist He Jiankui, convicted in his homeland for a dangerous genetic experiment, has resumed work with human embryos. The global scientific community not only does not approve of his experiments, but also doubts the results obtained.
Shocking news
The invention of the CRISPR-Cas9 method gave humanity a powerful tool for changing the very basis of life — DNA. It’s not for nothing that the technology is called “genetic scissors.” It has been used on human embryos since 2015, but experiments have always been interrupted at an early stage.
In November 2018, the American publication MIT Technology Review reported that volunteers were being recruited in China to test CRISPR-Cas9. We are looking for married couples with an HIV-positive father and a healthy mother who want to have children. Embryos conceived in vitro have their DNA edited to make them immune to the deadly infection and then implanted into the womb. The study is led by He Jiankui, a scientist from the Southern University of Science and Technology of China (Shenzhen).
It was on the eve of the International Human Genome Editing Summit in Hong Kong, where He was scheduled to speak. But since the secret was revealed, he hastened to explain, recording videos on YouTube and talking with an Associated Press journalist. The scientist said that two twin girls with an edited genome were born in China. They were designated by the pseudonyms Lulu and Nana. Another child will be born soon.
Why was the experiment on people needed
This caused shock in the scientific community and a flurry of criticism. In most countries, genetic experiments on humans are prohibited. Chinese authorities have initiated an investigation.
“Dr. He organized a group with the involvement of foreign personnel and since June 2016, deliberately evading checks, edited the genome of human embryos for reproductive purposes, which is prohibited in China,” Xinhua claimed.
< br />He Jiankui is no ordinary scientist. He is a physicist by training, studied in the USA, and there became interested in genetics. According to the talent program, he was returned home and literally showered with grants and bonuses. He opened several laboratories. His personal fortune was estimated at billions of yuan.
He justified himself by the desire to rid the world of dangerous diseases. “To make people better” is the title of a documentary film dedicated to him, released in 2022.
As scientists from China, Singapore and the UK note in their review, He Jiankui cannot be called a crazy loner. Everything was ready for this. A competition has unfolded in the world against the backdrop of the biotechnological revolution, in which two leaders have clearly emerged: the USA and China. In America there is stricter regulation; in China it was easier to carry out such work. And in general, the population there supports gene editing for medical purposes; clinics are massively treating with stem cells and experimenting with gene therapy for cancer. In an early interview with CCTV, He talked about inventing a genome sequencing machine that would «overtake the West.» «photo» data-crop-ratio=»0.5625″ data-crop-width=»600″ data-crop-height=»338″ data-source-sid=»rian_photo» title=»The egg is pierced with a capillary and an RNA solution is injected to genome editing» class=»lazyload» width=»1920″ height=»1080″ decoding=»async» />
That's not all. As it turned out later, He shared the results with a fairly wide circle of trusted people — scientists, entrepreneurs. Among them, for example, Michael Dim from Rice University in Houston (he was Professor He) and Yu Jun, founder of the Genome Institute of the Chinese Academy of Sciences. Although not everyone approved of his actions, no one allowed a leak. Jennifer Doudna, the discoverer of the CRISPR method, to whom He told about the birth of genetically modified children, did not believe him at first.
In December 2019, the case was sent to court. He and two of his colleagues were convicted of illegal medical practice. The scientist spent three years behind bars, lost his scientific reputation, and lost his university position and business. In the Western media, he was called «China's Frankenstein, a scoundrel,» and «endlessly immoral.» He was «thrown under the bus» by many of those he trusted, as bioethicist William Hurlbut of Stanford, an acquaintance of his, put it. He himself told The Guardian, after his release, admitted that he had rushed with this experiment.
How the genome of children was changed
HIV enters the body by infecting white blood cells. This is helped by human’s own receptors – CCR5. If they are not there, the virus is powerless. And there are such people, about ten percent of them on the planet. He wanted to artificially “turn off” the CCR5 gene. He assured that the mutation (delta32) would protect children from infection. However, as Vera Raposo from the University of Macau writes, sperm are cleared of the virus during the process of artificial insemination, meaning the risk of infection was minimal.
He never published a description of the experiment in scientific journals. We know about it only from the presentation at the summit. Careful analysis showed that genome editing in at least one child was not completed completely — only one copy of the gene was removed. This can lead to HIV infection, but the disease will develop more slowly. In addition, adds French researcher Bertrand Jordan, a child with both copies of CCR5 deleted had a random mutation between the genes. However, both embryos were implanted into the mother.
All this makes us think about the true motives of the experiment. Most likely, Raposo believes, scientists intended to monitor the development of children with different mutations.
Jordan believes that technically the experiment was apparently a success, but regards it as the first genetic manipulation of people and their descendants with an unknown result and a gross violation of ethics.
The international community has only indirect information about the consequences of the introduced mutations — from experiments over animals. There is, for example, evidence that deleting the CCR5 gene increases the risk of contracting West Nile fever and severe influenza. On the other hand, recent experiments on mice have demonstrated that this mutation makes them smarter. People with a congenital gene deletion recover more quickly from a stroke.
Children born in the experiment live normal lives in their families. According to He, they are completely healthy, Lulu and Nana go to kindergarten. The third child, born in 2019, is also a girl.
«An analysis of their genomes showed that only planned mutations were introduced. This confirms the safety of genetic editing. I am proud that I helped families give birth to healthy children,» he said recently He in an interview with a Japanese newspaper. The scientist reported that he had resumed research on editing human embryos, despite their controversial perception by society. Now he will focus on the treatment of rare hereditary diseases — Duchenne muscular dystrophy, familial forms of Alzheimer.
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