Monday , June 27 2022

The Chinese scientist says he is the first to genetically modify children: Shots


For the first time, a scientist claims to have used a powerful new gene editing technique to create genetically modified human children.

The scientist, He Jiankui of the University of Southern Sciences and Technology in Shenzhen, China, said he used human embryos modified with the CRISPR gene editing technique to create twin girls.

"Two beautiful Chinese girls named Lulu and Nana came to cry in the world as healthy as any other children a few weeks ago." He says in a video posted online. "The children are home now with their mother Grace and their father Mark."

He says his team has carried out a "genetic operation" on embryos created from sperm and their parents' eggs to protect children from the human immunodeficiency virus (HIV) that causes AIDS. Children's father is HIV-positive.

"When Lulu and Nana were just one cell, this surgery removed a door through which HIV infects people," he says in the film, one of several online articles to justify and explain the work.

Because research has not yet been published in a scientific journal or carefully examined by other scientists, many researchers and bioethics remain cautious about the claim.

But, if it is true, many said the move would be historic, comparing it with the birth of Louise Brown, the first child created by in vitro fertilization, IVF.

"This event could be similar to Louise Brown in 1978," wrote George Church, a prominent Harvard geneticist, in an email. "Both anecdotal and healthy children can have an impact," the Church wrote.

He and the Church are among the hundreds of scientists meeting at the second international summit on human gene development in Hong Kong. The Summit was organized to reach a global consensus on whether and how it would be ethical to create genetically modified human beings with CRISPR.

He says he immediately triggered generalized criticism from the summit participants and elsewhere.

This work is a break from the prudent and transparent approach of the global scientific community applying CRISPR-Cas9 to the human germline line, Jennifer Doudna, a biochemist at the University of California, Berkeley, said in an interview. Doudna helped discover CRISPR and organize the summit.

"All of us who are here at this conference strive to understand what has been done and also whether the process has been done properly. We do not know yet," says Jennifer Doudna.

But the statement "really reinforces the urgent need to limit the use of geno-editing in human embryos where there is a clear need for medical needs and where there is no viable alternative approach," says Doudna. She does not think this is the case.

If this was done to avoid HIV infection, there are alternative ways of preventing infections that are already effective, Doudna says, such as washing sperm of infected people to remove HIV.

"Why would you use this instead of an already established approach?" Doudna says.

For their research, he and his colleagues say they have used CRISPR to make changes in one-day embryos in a gene called CCR5. The CCR5 gene allows HIV to enter and infect immune system cells. Scientists have long sought ways to block this path to protect people from HIV.

His team used CRISPR to edit 16 embryos and implanted 11 embryos edited in the womb of women to try to create a viable pregnancy before the twin pregnancy was achieved, according to the Associated Press, who first reported his claims.

"No gene has been changed except to prevent HIV infection," he says. Gemini seems to be healthy and have undergone detailed genetic analysis. This verified the genetic operation worked safely, he says.

However, other scientists have asked whether editing really worked, and it is said that it is too early for the team to try the experiment.

"It is premature at this stage of technology," said Shoukhrat Mitalipov, a researcher at the Oregon University of Health and Sciences in Portland, Ore. Mitalipov was the first scientist to report the use of CRISPR to successfully edit human embryos, to use them to make copies.

Other experts agree.

Although I appreciate the global threat posed by HIV at this stage, the risks of embryo editing to eliminate CCR5 seem to outweigh the potential benefits, wrote Feng Zhang, a CRISPR pioneer at MIT. Zhang noted that destroying the CCR5 gene "will probably make a person more susceptible to the West Nile virus."

CRISPR allows scientists to make very precise DNA changes much easier than ever. As a result, it revolutionizes scientific research and raises great hopes for important breakthroughs, including the prevention and treatment of many diseases.

But the modification of human DNA, which could be passed by generations, has long been considered beyond the limits. One reason is that a mistake could introduce a new disease that could be passed on to generations. Another is that it could open the door to "design children" – children who are changed for non-medical reasons, such as being taller, stronger or smarter.

"If it is true as reported, then it is an extremely premature and questionable experiment in creating genetically modified children," agrees Jeffrey Kahn, a bioethicist at Johns Hopkins Berman's Bioethics Institute who attended the Hong Kong Summit .

But the development of CRISPR has led some scientists to rethink this ban for medical purposes. And researchers around the world have been racing to determine how it could be done safely. Many scientists believe it is inevitable, but should be limited to situations where there is no alternative.

"If it is true, it means a lack of ethical and indiscipline experimentation on human beings and serious human rights abuses," said Marcy Darnovsky, executive director of the Genetics and Society Center, a genetic surveillance group.

"Disposing of a door to a genetics society has and does not undermine our chances for a fair and just future," says Darnovsky.

He admits that his work might trigger criticism, but he defends the step.

"I understand that my work will be controversial, but I think families need this technology, and I'm willing to take criticism for them," he says.

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