Saturday , October 23 2021

China claims to be the first baby to genetically modify



[ad_1]


Hong Kong – A Chinese researcher says he helped create the first genetically modified babies in the world: two twins whose DNA he modified to try to help fight the possibility of future infection with the Human Immunodeficiency Virus (HIV).

If true, it will be a big leap in science and ethics.

A scientist from the United States said he participated in work in China, but the type of editing of this gene was banned in his country because DNA changes could be passed on to future generations and risked damaging other genes.

Many conventional scientists think that it is too dangerous to try, so some people denounce that the Chinese report is a human experiment.

Researcher He Jiankui, from Shenzhen, said he modified the embryos of seven couples during fertility treatment, and so far one pregnancy was produced. He reports that his aim is not to cure or prevent hereditary diseases, but to try to provide traits that few people naturally have: the ability to fight the possibility of future HIV infection, the virus that causes Acquired Immune Deficiency Syndrome (AIDS).

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

There is no independent confirmation of his claim, and has not been published in a journal, where other experts can examine it. The announcement was announced Monday in Hong Kong, one of the organizers of an international conference on gene editing which will begin on Tuesday, and earlier in an exclusive interview with The Associated Press.

"I feel a great responsibility that it is not only about making the first, but also about being an example," he told AP. "The community will decide what to do next" in terms of allowing or prohibiting the knowledge.

Some scientists were surprised to hear that claim and condemn it.

This is "unimaginable … an experiment with humans that is not morally or ethically maintained," Dr. Kiran Musunuru, an expert in genetic editing at the University of Pennsylvania and editor of the genetic journal.

"It's too early," said Dr. Eric Topol, who heads the Scripps Translational Research Institute in California. "We deal with the operational instructions of a human being, that's a big problem."

However, a well-known geneticist, George Church of Harvard University, defended genetic editing efforts for HIV, which he described as "a greater and ever increasing threat to public health".

"I think this can be justified," the Church said about that goal.

In recent years, scientists have found relatively easy ways to edit genes, DNA strands that regulate the body. The tool, called CRISPR-cas9, makes it possible to operate with DNA to provide the needed genes or deactivate the one that caused the problem.

Adults have recently tried to treat deadly diseases, and the changes are limited to that person. Editions of sperm, ovules or embryos are different, changes can be inherited. In the US, it is not permitted, except for laboratory research. China bans human cloning but does not specifically edit genes.

He Jiankui (HEH JEE -an-qway), who talked about "JK", studied at Rice and Stanford University in the United States. Before returning to his home country to open a laboratory at the South China University of Science and Technology in Shenzhen, where he also has two genetic companies.

The US scientist who worked with him on this project after returning to China was professor of physics and biotechnology Michael Deem, who was his adviser at Rice in Houston. Deem also has what he calls "small participation" in, and is part of the scientific advice of the two companies.

The Chinese researcher said he edited mice, monkeys and human embryos in the laboratory for several years and had filed a patent on his method.

He said he chose to test the embryo gene for HIV because this infection was a big problem in China. He tried to deactivate a gene called CCR5 which forms a protein gateway that allows HIV, the virus that causes AIDS, to enter cells.

All men in the project had HIV and all women did not, but editing the gene was not intended to prevent the risk of small transmission, he said. Parents experiencing infections are strongly suppressed by standard anti-HIV drugs and there are simple ways to prevent them from infecting children that do not involve gene changes.

Instead, the call was to offer HIV-infected couples the opportunity to have children who could be protected from the same fate.

He recruited a partner through the Beijing-based AIDS advocacy group called Baihualin. Its leader, known as a pseudonym "Bai Hua," told the AP that it is not uncommon for people with HIV to lose their jobs or have problems getting medical treatment if their infection is revealed.

This is how the work is completed:

Gene edition occurs during IVF, or laboratory plate fertilization. First, sperm are "washed" to separate them from semen, the fluid where HIV might hide. One sperm is placed in one ovule to create an embryo. Then a gene editing tool is added.

When the embryo is 3 to 5 days old, several cells have been removed and their edits are verified. Couples can choose whether to use an edited embryo for pregnancy or not. In total, 16 of the 22 embryos were published, and 11 embryos were used in six implant trials before twin pregnancies were reached, he said.

Evidence shows that one twin has both copies of the desired gene changed and the other twin is only one changed, without evidence of damage to other genes, he said. People with copies of genes can still get HIV, although some very limited studies show that their health can decline more slowly once they do.

Some scientists reviewed the material given to PA and said that the tests so far were not enough to say that the edition was successful or to get rid of damage.

They also observed evidence that the edition was incomplete and that at least one twin looked like a cell mosaic with several changes.

"It's almost like not editing anything" if only a few cells are changed, because HIV infection can still occur, the Church said.

The Church and the Musunuru questioned the decision to allow one of the embryos to be used in a pregnancy attempt, because Chinese researchers said they knew in advance that the two copies of the desired gene had not been changed.

"In that child, there really is nothing that can be obtained in terms of protection against HIV, but he exposes the child to all unknown security risks," Musunuru said.

The use of the embryo shows that the researchers' main emphasis is "testing the problem rather than avoiding this disease," the Church said.

Even if editing works perfectly, people without the normal CCR5 gene face a greater risk of contracting other viruses, such as West Nile, and dying of flu. According to Musunuru, there are many ways to prevent HIV infection and it is very treatable if that happens, other medical risks are a concern.

There were also questions about the way he said he continued. He gave official notice of his work long after he said he started it, on November 8, at a Chinese clinical trial registration.

It is not clear whether the participants fully understand the objectives and the possible risks and benefits. For example, the consent form calls the project a "AIDS vaccine development" program.

Rice scientists, Deem, said he was present in China when potential participants gave their consent and that he "really" believed they could understand the risks.

Deem said he worked with He on vaccine research at Rice and considered the gene edition to be similar to a vaccine.

"That could be the way ordinary people describe it," he said.

Both are physicists without experience in clinical trials in humans.

Chinese scientist He said that he personally made clear goals and informed participants who had never tried editing embryo genes and carried risks. He added that he would also provide insurance coverage for every child conceived through the project and plan medical follow-up until children aged 18 years or older if they agreed after they were adults.

Other attempts at pregnancy are still waiting until this security is analyzed and experts in the field do, but participants were not told in advance that they might not have the opportunity to prove what they registered once. reached "first" pregnancy, he admitted. Free fertility treatments are part of the care offered to them.

He submitted his application and received project approval at the Women's and Children's Hospital of Shenzhen Harmonicare, which was not one of the four hospitals he said provided an embryo for research or his pregnancy efforts.

Several staff from several other hospitals remained in the dark about the nature of the investigation, which according to him and Deem, was carried out to prevent HIV infection from some participants from being revealed.

"We believe this is ethical," said Lin Zhitong, a Harmonicare manager who heads the ethics panel.

Every member of the medical staff who handles samples that may contain HIV is conscious, he said. An embryologist at He's laboratory, Qin Jinzhou, confirmed to the AP that he washed sperm and injected gene editing tools in several pregnancy attempts.

The participants in this study were not ethics experts, he said, but "they have so many authorities about what's right as what's wrong because it's their life on the line."

"I think this will help their families and children," he said. If it causes unwanted side effects or damage, "I will feel the same pain as them and that will be my responsibility".

[ad_2]
Source link