In November 2018, Chinese scientist He Jiankui shocked the world when he announced, first on YouTube and then at an international scientific gathering in Hong Kong, that he had used Crispr to alter the genetic makeup of human embryos, which were used to establish pregnancies and resulted in the birth of the world’s first gene-edited babies. 

Backlash against He was harsh and swift. Members of the scientific community condemned his experiments as unethical and voiced concerns over the babies’ health, about which little is known today. The Chinese government suspended his research, saying he violated medical regulations. In December 2019, a Chinese court found He guilty of illegal medical practices and sentenced him to three years' imprisonment. In light of He’s experiment, China has since adopted regulations prohibiting the modification of human embryos for reproductive purposes. He was released from prison in April. 

In recent months, He has taken to Twitter and the Chinese social media platform Weibo to publicize his next steps. Previously a researcher at Southern University of Science and Technology in Shenzhen, He says he has started a new, independent lab in Beijing and wants to pursue gene therapy—an approach that attempts to correct inherited diseases by replacing faulty genes with new, healthy versions—as well as gene editing. In an email interview with WIRED, He said he wants to help families with rare diseases but plans to treat people who already have these disorders, not prevent them by making heritable changes to embryos as he did with the Crispr babies.

The first disease He wants to tackle is Duchenne muscular dystrophy, or DMD, a rare and devastating genetic disorder that causes gradual muscle loss and almost exclusively affects boys. “They are suffering,” He wrote in his email. “I want to help them.” 

He would not say how his lab is being funded or whether he has faced any challenges in raising money, but he said he has hired three employees and will be bringing on more. On Twitter, he said he hopes to raise 50 million yuan ($7.2 million) and launch a clinical trial for DMD by 2025. And he told WIRED that he wants to make gene therapy more affordable; the few that have been approved in the US and Europe can cost $1 million or more for a one-time dose. “The gene therapies we develop will be offered by a not-for-profit organization, and it is going to be affordable to most families,” He told WIRED, though he didn’t address specifics on how he plans to do that.

But his apparent return to science raises questions about whether researchers who engage in extreme misconduct should be accepted back into the scientific community, and how their subsequent work should be viewed. 

“I think he has the persistence and patience to come back to research,” says Samira Kiani, an associate professor of pathology at the University of Pittsburgh and the producer of the new documentary Make People Better, which chronicles the He affair. He didn’t give any on-camera interviews for the film, which instead used recorded phone calls between He and Arizona State University biomedical historian Benjamin Hurlbut, as well as promotional footage shot in 2018 by He’s hired PR team. Since He’s release from prison, Kiani has had a handful of Zoom and email conversations with him. “I think he has some noble intentions, but he’s also a very ambitious person,” she says.

Some scientists and ethicists think He deserves a chance to prove that he’s capable of producing scientifically valid and ethically sound work. “His case is publicly known enough that the world will judge his credibility,” says Sheila Jasanoff, professor of science and technology studies at Harvard University. “I think anything he says will be treated with considerable skepticism.” But she doesn’t see a moral basis for banning He from publishing future work if his research holds up to the peer-review process.

Others have concerns about He’s plans. “I would not want this guy anywhere near any sort of clinical trial or in a context in which therapies are being developed and given to patients,” says Kiran Musunuru, a cardiologist and gene-editing expert at the University of Pennsylvania who authored The Crispr Generation, a book about the history of gene editing and the Chinese babies.

“He did illegal and grossly unethical experiments in secret, and now he wants to pick up as if nothing happened,” says Hank Greely, a professor of law at Stanford University and author of the book Crispr People, which explores the science and ethics of human gene editing. “I don't think science should accept him back, at least not without some more time and some indication that he understands, accepts, and acknowledges that he screwed up.” Greely thinks for now, scientific journals should refuse to publish papers by He, and organizations outside of China should deny him research grants, but he’s not sure how long that prohibition should last.

He has not publicly apologized for his Crispr experiments, which were intended to make the babies resistant to HIV by using Crispr to create a mutation in a gene called CCR5. This trait occurs naturally in some people of European descent and blocks HIV from entering cells. But He’s data showed that the babies’ cells exhibited mosaicism—meaning the editing wasn’t uniform. It’s unknown whether the children have any health effects related to the editing.

At the 2018 genome editing conference in Hong Kong he defended his work, saying, “For this specific case, I feel proud, actually.” When asked by WIRED how he responds to criticism of his work as highly unethical, and whether he still holds the same opinion he did in 2018, he replied: "To answer your question, I will talk about it during my visit to Oxford University next March."

He was referring to an invitation from Eben Kirksey, an anthropologist at Oxford University who has written a book about the Chinese Crispr babies called The Mutant Project, and has invited He for a speaking event in the spring. The details and format of the event haven’t been worked out.

Academics are divided on whether He should be allowed to attend and speak at scientific events outside of China. In May, He was invited to a closed-door meeting hosted by the Global Observatory for Genome Editing, a group established in 2020 by Jasanoff and other academics to foster international dialogue about gene editing and society. “We wanted to find out more about the circumstances that led to his decision to do what he did,” Jasanoff says. “We were not interested in playing any part in a rehabilitation effort by He and took pains to construct our process in a way that would not be construed as giving him a platform.” 

Kiani says that He should be invited to international events as a way to “bring him to the table and have a respectful conversation with him.”

Kirksey takes a sympathetic view of He, whom he sees as someone who was a scapegoat for a scientific community that was already moving in the direction of creating children with edited genomes to prevent disease. “He saw himself at the vanguard, and in my opinion he got thrown under the bus,” Kirksey says. After He’s experiment came to light, so too did the fact that many prominent scientists, within China and elsewhere, knew about He’s plan to establish pregnancies with edited embryos and failed to stop it.

In his replies to WIRED, He did not directly address his previous Crispr work but seemed to acknowledge indirectly that he’ll have to work to establish trust within the scientific community. He has been widely criticized for carrying out his Crispr experiment in relative secrecy and failed to obtain proper ethics approval or informed consent from participating families. Now, he wrote, “My research work will be transparent and open,” adding that he plans to have an international scientific advisory team review his research and an ethics review board to monitor his work. “All progress will be posted on Twitter.”

Following the news of the Crispr babies, researchers sought to prevent more such incidents. Top Chinese bioethicists advocated for a reboot of the country’s medical research regulations. Meanwhile, leading scientists in the West called for an international moratorium on heritable genome editing until nations established laws governing such research. The World Health Organization and the US National Academy of Sciences have both put forth guidelines on how these experiments could hypothetically proceed, but in the US, China, and many other countries, editing human genes in this way is prohibited. 

But Musunuru points out that there’s still no mechanism by which scientists can report ethically dubious or potentially illegal research activity, especially across borders. A proposed global registry of genome editing research in embryos has also stalled. 

“The individual researcher may deserve a second chance. But the more difficult challenge is developing adequate institutional mechanisms to prevent similar misconduct,” says Jing-Bao Nie, an expert on Chinese bioethics at the University of Otago in New Zealand. “An even more difficult challenge is critically examining and effectively reforming the social and political environment that nourishes this kind of scientific misconduct.” 

Musunuru also notes that the kind of gene therapy research He wants to do is far from risk-free. In 1999, 18-year-old Jesse Gelsinger died after being given an infusion of an experimental gene therapy. The incident put a freeze on the entire gene therapy field, and the investigator behind the trial was temporarily banned from working on clinical trials, although he made a comeback after spending years dedicated to developing safer gene therapies.

On Weibo, He acknowledged the risks of gene therapy and gene editing, pointing out the recent death of a man with DMD who received a personalized Crispr treatment as part of a research study. “History tells us that when any new technology emerges, it is both an angel and a devil,” He wrote on the site.