The Second International Summit on Human Genome Editing, held in Hong Kong last November, was meant to debate the pros and cons of genetically engineering humans. Instead, the proceedings were turned upside down by the revelation that He Jiankui, a Chinese biophysicist, had already done it.
He’d gone ahead and edited the DNA of twin girls with the powerful gene modification tool called CRISPR.
Then the Chinese scientist sprang a further surprise on the shocked gene-editing experts. A second Chinese woman, he said, was pregnant with yet another CRISPR baby. An early pregnancy test had confirmed it.
That third CRISPR baby is now due to be born at any moment—if he or she hasn’t come crying into the world already.
Seven months have passed since the Hong Kong summit, but because the pregnancy was already under way by then, it is now at term, according to William Hurlbut, a Stanford University physician and ethicist who was in regular communication with He starting in 2017 and is familiar with the time line of events. Hurlbut knows the day the third baby was conceived but won’t make it public, because of the risk the information could identify the parents and child.
“What I can say is that a normal birth is 38 to 42 weeks, and it’s pretty close to the center of that,” Hurlbut told MIT Technology Review.
Now the guessing game among CRISPR watchers is whether China’s government will ever acknowledge the third CRISPR baby. Rosario Isasi, a bioethicist at the University of Miami, says she has encouraged science leaders there to “make a statement and do damage control.”
But the government may not want more attention, and experts in China are reluctant to discuss He’s experiment on social-media networks such as WeChat, which are monitored. “The government is extremely aware of any transgressions. They have the Tiananmen anniversary, they have the Hong Kong protests, and they have the CRISPR babies,” says Isasi.
Once it became public, the Chinese CRISPR experiment was widely condemned and quickly halted. However, many experts fear that more CRISPR babies are inevitable. Despite calls for a global moratorium, it is impossible to control access to the gene-altering technology, which is relatively easy to use. In June, a scientist in Moscow said he hopes to be next to make CRISPR babies if he can win approval.
On November 25, MIT Technology Review first revealed that He had employed CRISPR to get women pregnant with genetically edited babies. Within hours, the Chinese biophysicist posted a series of YouTube videos, claiming his experimental editing of human embryos had led to the birth of “two beautiful little Chinese girls,” fraternal twins whom he called Lulu and Nana.
His team had used CRISPR to damage a single gene, called CCR5, in an attempt to make the girls immune to infection by HIV.
Instead of being cheered as a science hero, He was roundly criticized by observers around the world, including in China, for carrying out a risky and medically pointless experiment. Two days after posting his videos, He, until then a relatively unknown figure, made his dramatic appearance at the Hong Kong summit, where he was allowed to present his experimental results. It was during questioning by the British developmental biologist Robin Lovell-Badge that He said yet another CRISPR baby was on the way.
“Just to be clear, are there any other pregnancies with genome editing as part of your clinical trials?” Lovell-Badge asked.
“There is another one, another potential pregnancy,” He replied. The pregnancy had been detected with a blood test, meaning it was at least two weeks along at the time.
Because He had by then already received threats, the Chinese biophysicist, widely known as “JK,” had hidden in a room prior to his appearance in Hong Kong and was immediately escorted away by university security officials afterwards. “The whole idea was to get JK to talk, because we knew that this would be the only opportunity that most people would have of interacting with him,” Lovell-Badge would later write as part of a history of the fast-moving events surrounding the summit.
Indeed, He has not been seen or heard from since January, when Chinese investigators accused him of potential crimes. At the time, they also confirmed that the second pregnancy was still under way, and that the mother was under medical observation. Although it’s possible the pregnancy was later terminated, Hurlbut doubts it: “I don’t know any reason to suspect that the pregnancy was not proceeding normally,” he says. He says the third baby also had its copies of CCR5 removed.
It remains unclear whether He’s team established the second pregnancy after the CRISPR twins were born or shortly before. In either case, he may have felt confident his experiment was going to be a success. “He really believed what he was doing was bringing glory to his homeland. The thing that surprised him the most was that he was criticized in China,” says Hurlbut.
The timing of events also means that some American scientists and journalists who by then knew about He’s undertaking did not stop the third baby from being created. These include Nobel laureate Craig Mello of the University of Massachusetts, Stephen Quake of Stanford University, and journalists from the Associated Press, all of whom kept He’s experiments confidential. For his part, Hurlbut regrets he wasn't able to convince He not to proceed. “I felt that if I had had one more long talk with JK, I might have stopped him,” he says.
Now the question is whether Chinese authorities will acknowledge the birth of the third child. One thing that He and other scientists agreed on at the summit is that scientific data about the CRISPR babies should be made public. Scientists will want to know the results of editing on the child’s genome. Another baby would be further evidence that CRISPR, despite the controversy surrounding its use, “can produce live births,” Hurlbut says.
Earlier this year, China’s government took steps to clarify its laws and procedures on gene editing, including introducing new penalties. However, Isasi, who has participated in meetings of the Chinese Academy of Sciences, says that bioethicists and others in China continue to “express a lot of frustration over the lack of transparency” in connection with the ongoing He investigation.
“If you look at the big picture, there is a concerted effort by the Chinese government to change the regulatory framework. So why would they keep it secret?” she says. “But they can if they want, and the world will never know. The Chinese government owes it to the international community to live up to the accountability they have promised.”
One thing most people agree on is that the actual identities of the three babies and their parents should never be made public. If their names were known, the kids might grow up with unwelcome attention for having been created by a scientist once dubbed “China’s Frankenstein.”
“The Chinese realize there is a need for privacy, not to make it into a circus,” says Isasi.
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