Tuesday , June 28 2022

The first human genetically modified babies claimed in China


A Chinese researcher claims to have helped make the world's first genetically engineered copies – twin girls born this month, whose DNA said they were modified with a powerful new instrument capable of rewriting the plan of life.

If that were true, it would be a profound leap of science and ethics.

An American scientist has said he has been involved in Chinese activity, but this type of gene editing is forbidden in the United States because DNA changes can pass on to future generations and risk damaging other genes.

Many ordinary scientists believe it is too uncertain to try and some have denounced the Chinese report as human experimentation.

The researcher, El Jiankui of Shenzhen, said he had modified the seven-coupled embryos during fertility treatments with a pregnancy that has been achieved so far. He said his goal was not to cure or prevent an inherited disease but to try to provide a feature that few people naturally have – the ability to resist future HIV infection, the AIDS virus .

He said the involved parents refused to be identified or interviewed, and he would not say where they lived or where the work was done.

There is no independent confirmation of his claim and was not published in a journal, where he would have been checked by other experts. He revealed on Monday in Hong Kong to one of the organizers of an international genetics conference that is due to start Tuesday and earlier in exclusive interviews with The Associated Press.

"I feel a strong responsibility that it's not just making a premium, but also making it an example," he said. "Society will decide what to do next" in allowing or prohibiting such sciences.

Some scientists were amazed to hear about the claim and condemned him firmly.

It is "unthinkable … an experiment on human beings that is not morally or ethically defensible," said Dr. Kiran Musunuru, an editor of the gene at the University of Pennsylvania and editor of a genetics journal.

"This is far too early," said Dr. Eric Topol, who runs the Scripps Research Translational Institute in California. "We're dealing with the operating instructions of a human being. It's a big deal."

However, a well-known geneticist, George Church at Harvard University, defended the attempt to edit the gene for HIV, which he called "a major and growing public health threat."

"I think this is justified," the Church said.

In recent years, scientists have discovered a relatively easy way to edit genes, the DNA components that govern the body. The tool, called CRISPR-cas9, makes it possible to run on DNA to provide a necessary gene or disable one that causes problems.

Only recently has been attempted in adults to treat deadly diseases, and the changes are limited to that person. Editing sperm, eggs or embryos is different – changes can be inherited. In the U.S., it is not allowed, except for laboratory research. China uses human cloning, but it does not specifically generate the gene.

He studied at the Rice and Stanford universities in the United States before returning to his homeland to open a laboratory at the Shenzhen University of Science and Technology in China, and he also has two genetics companies.

The US scientist who worked with him on this project after returning to China was Physics and Bioengineering Professor Michael Deem, who was his advisor to Rice in Houston. We also hold what he called "a small stake" in – and he is in counseling councils – He is two companies.

The Chinese researcher said he practiced for many years mice, monkeys and human embryos in the lab and asked for patents on his methods.

He said he chose to edit the embryonic gene for HIV because these infections are a big problem in China. He tried to disable a gene called CCR5 that forms a protein door that allows the HIV virus that causes AIDS to enter a cell.

All men in the project had HIV and all women did not, but gene editing does not aim at preventing the low risk of transmission, he said. Fathers have had profoundly suppressed infections by standard HIV drugs and there are simple ways to prevent them from infecting offenders that do not alter genes.

Instead, the call was to give HIV-affected couples the chance to have a child who might be protected by a similar fate.

He recruited couples through a Beijing AIDS advocacy group called Baihualin. His leader, known as the "Bai Hua" pseudonym, told AP that it is not unusual for people with HIV to lose their jobs or have problems with medical care if their infections are revealed.

Here's how the work described:

Modification of the gene occurred during fertilization with IVF or in the laboratory. First, sperm was "washed" to separate it from semen, the fluid in which HIV can be seen. A single sperm was placed in one egg to create an embryo. Then added the gene editing tool.

When the embryos were 3 to 5 days old, a few cells were removed and checked for editing. Couples could choose whether to use embryos that were edited or needed for pregnancy trials. In total, 16 of the 22 embryos were edited and 11 embryos were used in six implantation trials before the twin pregnancy was reached, he said.

The tests suggest that only one twin had both copies of the intended modified gene and the other twin had only one modified without any evidence of other genes, he said. Individuals who have only one copy of the gene can still get HIV, although some very limited research suggests that their health might fall more slowly once they did.

Several scientists have analyzed the materials the AP provided and said that until now tests are not enough to say that editing worked or to exclude evil.

They also noticed evidence that editing was incomplete and that at least one twin seems to be a mosaic of cells with various modifications.

"It's almost like it would not have been edited at all" if only some of the cells were changed because HIV infection may still occur, the Church said.

The Church and Musunuru questioned the decision to allow one of the embryos to be used in a pregnancy test because the Chinese researchers said they knew in advance that both copies of the intended gene were not altered.

"In that child, there really was almost nothing to gain in terms of HIV protection, and yet you expose this child to all the unknown safety hazards," Musunuru said.

The use of this embryo suggests that the primary focus of the researchers was to test the edition rather than to avoid this disease, "the Church said.

Even though editing has worked perfectly, people without CCR5 normal genes face greater risks of getting certain viruses, such as West Nile, and die of influenza. Because there are many ways to prevent HIV infection and is very treatable if it occurs, those other medical risks are a concern, said Musunuru.

There are also questions about how he said he did. He gave an official note about his work a long time after he said he started it – on November 8, on a Chinese registry of clinical trials.

It is not clear whether the participants have fully understood the purpose and potential risks and benefits. For example, consent forms call the project a "AIDS vaccine development" program.

Rice scientist Deem said he was present in China when potential participants gave their consent and that "absolutely" believes he is capable of understanding the risks.

We say he has worked with him on Rice vaccine research and believes that gene editing is similar to a vaccine.

"That could be a way to describe it," he said.

Both men are physical experts with no experience in conducting clinical trials in humans.

The Chinese researcher, He, said he personally made the goals personally and told the participants that editing the embryonic gene was never attempted and involves risks. He said he would also provide insurance coverage for all children conceived through the project and plan medical follow-up until the children are 18 years of age and older if they agree that they are adults.

Other pregnancy attempts are pending until the safety of this is being analyzed and experts in the field are weighing, but the participants were not told beforehand that they might not have the chance to try what they did for once they were " first, "he admitted. Free fertility treatment was part of the business they were offered.

He sought and received approval for his project at the Shenzhen Harmonicare for Women and Children, which is not one of the four hospitals He said he had provided embryos for his research or pregnancy trials.

Some employees of some of the other hospitals were kept in the dark about the nature of the research, which El and Deem said they had done to prevent the disclosure of HIV infection to some participants.

"We think this is ethical," said Lin Zhitong, managing director of Harmonicare, who runs the ethics panel.

Any medical staff who manipulated samples that might contain HIV were aware, he said. An embryologist in Hei's laboratory, Qin Jinzhou, confirmed that AP had done the sperm wash and injected the gene editing tool in some pregnancy attempts.

Study participants are not ethical, he said, but "there are as many authorities as to what is right and what is wrong because their lives are on the line."

"I think this will help their families and their children," he said. If it causes side-effects or bad unwanted effects, "I would feel the same pain as they are and it will be my own responsibility."

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