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CRISPR babies: Is this the start of a daunting new chapter in gene editing?



A Chinese scientist shocked the world this week by reporting on a well-coordinated media campaign that included exclusive AP videos and YouTube videos that he had created the world's first CRISPR genetically-engineered babies: a series of twin girls with a third potential CRISPR baby on the way.

Nearly a week later, He Jiankui's experiment was not fully tested. However, it is the realization of the fears of many scientists who believe that CRISPR is not yet safe and precise enough to be used in human embryos.

He says he is "proud" of his work – and it has more to do with public health than "designer babies" because he wanted to eliminate the risk of HIV infection among babies.

But when a rogue scientist quietly tinkering in a laboratory breaks through norms and interferes with the human genome to satisfy his own ego or scientific curiosity, there is concern that there are many more dangerous uses of CRISPR Bearings are. What if others experiment with CRISPR in a way that threatens human life? What if they use CRISPR to improve human characteristics and usher in a new era of genetic inequality?

While some of them call recklessly, others call this a timely and necessary next chapter in CRISPR history. Let's unpack the controversy.

We still do not know if these CRISPR babies really exist.

Recent years in science have sparked the CRISPR revolution. CRISPR / Cas9 ̵

1; or CRISPR, as it is known – is a tool that researchers use to control which genes are expressed in plants, animals and even humans. delete unwanted features and possibly add desirable features; and do it all faster and more accurately than ever before. (You can read how CRISPR works here.)

He, a Stanford-trained associate professor at Southern University of Science and Technology, Shenzhen, China, was not widely known in CRISPR editing. He claims, however, a great premiere: he has used the gene editing technology CRISPR to alter the DNA of human embryos during in vitro fertilization.

If his experiment is confirmed, he would be the first known scientist to use CRISPR to process human embryos, leading to a live birth, defying the unofficial international moratorium on processing human embryos intended for pregnancy , (Chinese scientists were also the first to work on non-viable human embryos, which can not lead to childbirth.)

It's an experiment first reported by MIT Technology Review and AP on Sunday, but it has not published in a scientific journal His data has not been officially reviewed by experts. He says it is self-financed and he has the consent of the parents.

However, he did not want to disclose the identity of the babies and parents involved, and just shared some data in an excel spreadsheet with the International Human Issues Editing Summit in Hong Kong before a brief presentation on the second.

Researchers who reviewed the information he publicly shared have found that it is too sparse to understand what his team actually did, whether the editing worked and whether it was safe.

Said that in a journal, however, it had not yet announced that it had enough data, so that the course of the experiment and the experiment had actually taken place-it was easier to check

The reasons for the experiment

At the moment He is defending his work. The stated aim of his experiment was to deactivate a gene called CCR5, so that the girls may be resistant to infection with HIV / AIDS. And he justified his experiment in two ways: First, he made a human case in the Hong Kong meeting and said that the girl's father had HIV and wanted to make sure that his children would never suffer the way he did. Second, he made a scientific case: in a YouTube video, he said that CCR5 is a well-studied genetic mutation, and there is "a real medical value" to find out how CRISPR can be used to prevent HIV and prevent HIV / AIDS. In other words, he considered the use of CRISPR technology to be medically appropriate.

"Please keep in mind that while there are vociferous critics, there are many silent families who have seen a child suffer from a genetic disorder and do not have to suffer the pain again," he said on one of the YouTube sites videos. "Although you are not the director of an ethical center quoted by the New York Times, you are no less authority for what is right and wrong – because it is your life."

Critics of the CRISPR babies include the technology co-founder – and the university he was a member of

Many people in the science community in China, as well as scientists working on gene processing technologies elsewhere this reasoning too. And now there are investigations into his work and his behavior.

The Southern University of Science and Technology, where he has taken unpaid leave since February, said he did not know about the research that took place outside the campus. It has instituted an investigation against He that may violate the university's ethical rules.

"He uses CRISPR / Cas9 to process human embryos and has seriously violated academic ethics and behavioral codes," the university said in a statement. "The University will call on international experts to form an independent committee to investigate this incident and make the findings available to the public." On Tuesday, CNN reported that China's National Health Commission is launching an investigation into allegations. The hospital where the babies were allegedly born, the Shenzhen Harmonicare Women's and Children's Hospital, now distances itself from him.

Side Note: There are wrinkles in the versions of the hospital and the university. As the Washington Post reported, a hospital director appeared in an AP video in which he was greeted by his work. And the consent he used says that his university helped fund the experiment. So it's possible he was not the rogue operator he painted himself.

But some of his science colleagues who deal with gene editing and ethics are not satisfied with the experiment. He has broken a scientific taboo to eliminate a disease that is now very treatable – with a potentially dangerous and unproven technique. Hank Greely a Stanford professor of law and ethics, called the experiment "ruthless [because] of a terrible benefit-risk balance for the baby." Others have called the experiment "outrageous" called. "Unreasonable" and "premature" and 122 Chinese scientists wrote a joint statement denouncing the work.

Especially the co-inventors of CRISPR are disturbed by the move of He. Feng Zhang, a member of the Broad Institute of MIT and Harvard and co-inventor of CRISPR / Cas9, called for a moratorium on genetically-born babies.

Jennifer Doudna, a co-inventor of CRISPR from the University of California Berkeley, said in a statement that "this work reinforces the pressing need to limit the use of gene editing in human embryos to environments where there is a clear medical history There is a need, and where no other medical approach is a viable option, as recommended by the National Academy of Sciences.

Nobel laureate David Baltimore said the experiment showed that there was a failure of self-regulation in the scientific community. And that's the scary truth. It's reappeared: the scientific community can not necessarily protect the public from clumsy scientists using CRISPR for potentially dangerous applications, including promoting human evolution, improving humans by selecting specific traits, or using them from CRISPR to increase inequality.

Some prominent scientists are less worried and even support Ers work.

However, there are at least a few prominent researchers who have participated in He, including the Harvard University's George Church, another pioneer of the CRISPR. In a lengthy interview with Science Magazine, Church stated that when the children experiment normal and healthy, the babies may be more likely to see Louise Brown (the first baby born through in vitro fertilization) as Jesse Gelsinger (who died early) gene therapy experiment).

"At some point we have to say we have done hundreds of animal studies and we have done some human embryo studies," Church told Science. "It may be that the dust has settled once, because there are mosaicism and wrong targets that affect medical outcomes. It must never be zero. We do not wait for the radiation to be zero before we do [positron emission tomography] scans or x-rays. "

Similarly, Dr. George Daley, Dean of Harvard Medical School, at the Genk meeting in Hong Kong: It is time to set [debates about] the ethical permissiveness to point the way to clinical translation … to advance this technology. "

Daley continued," The fact that the first processing of the human's germ line turns out to be the misstep should not put our neck in the sand. I do not believe that a single practitioner who violates the norms of the field is a failure of scientific self-regulation. "Harvard researchers are actually starting to use CRISPR to tinker with sperm DNA, although this is not intended for pregnancy only in embryos.

Researchers still call for a "take it slow" approach to CRISPR in humans

So far, the scientific consensus continues: Most experts believe that CRISPR is not suitable for crafting in humans.

2017 National Academies of Science reported on the editing of genes that clinical trials in the future might be "greened for serious conditions under strict supervision". But "the editing of genomes for improvement should not be allowed at this time."

That's the real bounds to what CRISPR can do, at least now. Scientists have recently discovered that the gene processing approach can inadvertently obliterate and rearrange large sections of DNA in ways that can endanger human health. This follows recent studies showing that CRISPR-treated cells can unintentionally trigger cancer.

According to Stat, he visited Feng Zhang's lab in August and asked how he could reduce some of these risks. "I knew he had the same challenges as other researchers in terms of lack of efficiency and lack of precision," Zhang said. "I told him that the technology is neither efficient nor precise enough to be used in embryos in practice, even when using human IVF."

Therefore, scientists have generally advocated a slow, cautious approach to gene processing of human embryos. All the more shocking are the news from China.

"I feel a strong responsibility that it's not just about making a debut, but also being an example," he said. If others follow his example, he added, "Society will decide what to do next." Or, before society agrees on anything, He and other scientists may continue to move forward.


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