CRISPR babies, edited by genes from China, propel bioethics into a bleak new age – Quartz


This was going to happen sooner or later.

A group of scientists in China say they helped give birth to two genetically edited babies. The goal was to modify the genes of twin girls to prevent HIV infection and prevent AIDS. Scientists say they were successful in this effort, according to reports by the Associated Press and the MIT Tech Review.

The claims have not yet been independently verified. But if researchers really are against internationally recognized voluntary guidelines and do what they say, both science and bioethics are entering uncharted territory.

What's new?

The genetic editing project was led by He Jiankui, a researcher at the Southern University of Science and Technology in Shenzhen. The twin girls, named Lulu and Nana, were born with Mark and Grace, who are part of a clinical trial involving seven couples. Men in the tests are all HIV positive, while women are not.

The couples underwent in vitro fertilization (IVF) in which a sperm is injected into an egg in a Petri dish and after a few days a live embryo is planted in the mother's uterus. In this case, however, there was a slight adjustment. After the sperm was injected into the egg, He's team injected Crispr-Cas9, a genetic tool that can accurately target and cut a specific gene among 20,000 human genes. In this case, the target was the CCR5 gene. As Quartz previously reported:

CCR5 is responsible for producing a protein that HIV uses to trap, enter and infect a human immune cell. If the CCR5 gene were mutated, logically, the HIV virus would not be able to infect – and thus the mutation would confer resistance to the disease.

In that case, the HIV infection of the parents has already been suppressed with the use of drugs, which would have ensured that the offspring did not carry the disease. The appeal of the clinical study was to show that it may be possible for children Never be infected by the disease throughout their lives. The consent forms signed by participants called the project "development of AIDS vaccines," according to the Associated Press.

The trial runs until March 2019, according to test documents on the He's lab site. So far, there has been only one successful pregnancy.

AP Photo / Mark Schiefelbein

He Jiankui, left, and Zhou Xiaoqin work at a computer in a laboratory in Shenzhen, Guangdong Province, southern China.

What are the claims?

Until very recently, scientists trying to modify the CCR5 gene in human embryos ended up with poor results. A 2016 study, conducted by a separate group of Chinese researchers, was able to genetically modify only four of the 26 embryos. Even among those, not all copies of the CCR5 gene were modified. Worse still, many embryos have undergone involuntary mutations. None of the embryos were brought to term.

It does not say how many embryos have been tested in the clinical trial so far. What he says in videos uploaded to YouTube is that the two genetically engineered embryos that were brought to term – namely Lulu and Nana – proceeded as planned. This goes against the 2015 guidelines of the International Summit on Human Gene Editing, which concluded that "if, in the research process, early human embryos … undergo genetic editing, modified cells should not be used to establish a pregnancy."

And it may not be the full story because the results have not been verified by other scientists. The data on the clinical study website show that one of the fetuses of twin girls before birth has a mix of cells that are edited differently, meaning that some cells have the ability to resist HIV while others do not.

In other videos on He's YouTube, he says that Lulu and Nana are not designer babies. He is using the powerful Crispr gene-editing tool just to "heal" families. "If we can help families protect their children, it's inhuman for us not to," he says. "We believe that ethics is on our side."

He devised his own ethical principles for using technology, which he invited people to discuss and comment on:

  1. Mercy for Needy Families
  2. Only for serious illness, never vanity
  3. Respect the autonomy of a child
  4. Genes do not define you
  5. Everyone deserves freedom from genetic disease

AP Photo / Mark Schiefelbein

Zhou Xiaoqin adjusts a monitor showing a video of Qin Jinzhou moving a thin glass pipette containing Cas9 protein and ssRNA PCSK9 to an embryo under a microscope in a laboratory in Shenzhen, Guangdong province, southern China.

What are the reactions of other scientists?

News of He's experience has been met with widespread criticism. Issued in 2015, the most recent guidance on the use of Crispr in humans by the world's leading scientists cautiously approves the use of genetic editing tools in human embryos, but only under rigid research guidelines and without bringing the embryo to term. Letting Lulu and Nana be born, He ignored these instructions.

"In this increasingly competitive global search engine for gene editing applications, we hope to be a highlight," he and his team wrote in an ethics statement they submitted last year, according to the MIT Tech Review.

A group of 100 scientists in China and around the world condemned the research, writing that the experience of He opened the Pandora's box. "The approval of bioethics for this so-called & # 39; study & # 39; was insufficient. "We, as biomedical researchers, strongly oppose and condemn any attempt to edit genes in human embryos without scrutiny on ethics," the statement said. and security!"

Fyodor Urnov of the Altius Institute of Biomedical Sciences joined the chorus of criticism, expressing to the MIT Tech Review "regret and concern that gene editing – a powerful and useful technique – has been put into practice in an environment not necessary. "

"In cases where the potential risks are substantially higher than the potential benefits, which I think is the case here, this is unethical," Kiran Musunuru of the University of Pennsylvania told The Associated Press.

If true, the study "would be premature and reckless intervention for many, many reasons" tweeted Peter Mills of the Nuffield Center for Bioethics.

Some were more moderate in their assessment. George Church, a geneticist at Harvard Medical School, told The Associated Press that the decision to use genetic editing to prevent HIV was justified because of the global burden of the disease. But he was not happy with the way the study was conducted, especially when the embryo with just a few of the genetically edited cells was also carried over.

Feng Zhang, a geneticist at the Broad Institute and one of the world's leading scientists, went as far as calling for a global moratorium on implanting published embryos in uterus. "Not only do I see this as risky, but I am also deeply concerned about the lack of transparency surrounding this judgment," he said in a statement.

What's next?

In a way, what He's laboratory should not surprise. The Crispr technology is so widely used that it was inevitable that someone would apply it to genetically modify the embryos and bring them to term. The advantage is that we know that such an experiment has happened and He seems open to comment and dialogue. The downside is that it is not clear whether these dialogues will result in a more rigorous working environment.

Gene-editing technologies have the potential to be extremely beneficial to mankind. But there are also big risks because these modified genes would be passed on to other humans for generations. Currently, there are no global regulations governing the use of IVF techniques or the genetic modification of human embryos. What exists is a set of guidelines that researchers can voluntarily agree upon. He clearly disregarded these guidelines in his experiments in favor of his own principles. This is unlikely to go well with the scientific community or society at large.

The news of Lulu and Nana comes just a day before the world's most prominent scientists meet in Hong Kong, a short train ride from Shenzhen at the second International Human Gene Editing Summit.

"We hope this series of meetings will provide guidance, provide a way for the scientific community to interact with the general public," Nobel Prize winner David Baltimore said in a pre-recorded video of the meeting. "We have to come together to come to an agreement about what we want to do, how we want to do it and what we regard as right and wrong on a voluntary basis. Our hope is that the advances of science will be available to the whole world. "

Your study will inevitably be an important point of discussion. If humans have opened the Pandora's Box, it will be very difficult to close.


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