"CRISPR Baby" Creator Reveals Details of His Rogue Gene Editing Experiment

"The volunteers were informed of the risk."

At an international genetics conference in Hong Kong on Tuesday, He Jiankui, Ph.D., the Chinese scientist who claimed to have created the world’s first genetically modified “designer babies,” both defended his decision to go rogue and perform heritable edits on healthy human embryos and dropped another startling piece of news. He’s standing by this work, and there’s already another potential designer baby in the works.

In an interview with AP published Monday, He claimed to have modified the genes of two embryos, which developed into two healthy twin girls, Nana and Lulu. The gene edits are said to have conferred HIV resistance to one of the girls, although both embryos were healthy before editing. Before He took the stage at the Second International Summit on Human Genome Editing, a moderator announced to the crowd that he had “the right to cancel the session if there is too much noise and interruption.” This was a needless warning: The auditorium was silent as He explained his intentions, his collaborators, his methods, and the serious ethical considerations behind his work.

Who Knew About His Intentions?

It’s unclear whether the Southern University of Science and Technology, where He runs his genetics lab, knew about He’s intentions. (Their official statement says no.) The hospital where the children were born, Shenzhen HOME Women’s and Children’s Hospital, has also denied knowledge of He’s intentions to Chinese media, but ethical review board documents show that at least someone on the hospital’s medical ethics committee signed off on this experiment.

The real ethical question, however, is whether the twins’ parents understood what He was planning with their embryos when he handed them the consent form? He maintains that they did.

He takes questions following his breakdown of his "designer babies" experiment 

National Academies

“Yes. I explained from page one to page 20, line by line, paragraph by paragraph,” He explained in a Q&A during the conference. “Once we went through the entire informed consent, at the end I gave them time [for] private discussion so that they had some time to discuss as a couple. They also had the choice to decide to take it home and decide later.”

The full consent form, he added, can be found on his lab’s website.

Of course, walking someone through a consent form doesn’t guarantee comprehension. When pushed on the parents’ understanding of the risks and implications of genome editing, He doubled down by saying that the parents were “well educated.”

Were Other Scientists Involved?

One of the major concerns around this work is that it was conducted largely in secret, without the input of other scientists. But it has become clear that some scientists were aware of his project. Rice University is investigating the potential input of bioengineering professor Michael Deem, Ph.D. Furthermore, two Stanford University professors, William Hurlbut, Ph.D., and Matthew Porteus, Ph.D., also noted that they were both in contact with He before he announced the twins’ birth to the world but also condemned his actions to the AP.

"“ I continued to talk with not just scientists but also the top ethicists in the United States such as at Stanford and Harvard."

He confirmed that he was in contact with scientists in the US during the talk on Tuesday.

“I received positive feedback and also some criticism and also some constructive advice. I continued to talk with not just scientists but also the top ethicists in the United States such as at Stanford and Harvard,” He said. “Also I showed by preclinical data to visiting scientists.”

He also mentioned that a “US professor” reviewed his consent documents, though he didn’t provide further details.

How Did The Experiment Go Down?

He’s presentation shows that, while the twins were born healthy and normal, the editing itself didn’t go entirely to plan. A major concern in this area of research is that performing a genetic manipulation to say, promote HIV resistance, might cause other unintended mutations. There’s been heated back and forth in the scientific community about how CRISPR may have these unintended effects.

"“The volunteers were informed of the risk of this one existing off-target, and they decided to implant the embryo."

He admitted he found one off-target mutation in Lulu’s genome that may be due to CRISPR, though the mutation was in a far-flung area of the genome and likely won’t be expressed.

Nevertheless, the unintended mutation exists, and not everyone is convinced that He used accurate methods to detect those off-targets in the first place. On Twitter, Australian National University geneticist Gaetan Burgio, Ph.D., called it “not good enough.”

He says he informed the parents of this off-target, and they proceeded anyway. “The volunteers were informed of the risk of this one existing off-target, and they decided to implant [the embryo],” He said.

An overview of He's approach

National Academies 

Complicating the matter, only one of the twins has two copies of the gene conferring HIV resistance. The other twin has a deletion of genetic material in that manipulated gene, which indicates that she won’t have the same HIV resistance as her sister.

“The parents were informed of the implication of this related to HIV infection,” He continued. We reminded them of the option to leave the trial without implantation, or to choose the embryos. The couple elected to implant this embryo to start a two-embryo pregnancy.”

Plans for the Future

He plans to continue monitoring the twins for the next 18 years, surveying them for HIV as well as any other consequences that might arise from the genome manipulation. He also added that there’s another early stage pregnancy from a genetically modified embryo in the works, though right now, it’s unclear whether that embryo is viable.

As for Nana and Lulu, they’ll spend most of their childhoods in contact with the team that altered their genetic material.

“There is a plan to monitor the children for the next 18 years, with the hope that they will consent as adults for continued monitoring and support,” He said.

He however, has decided to stop answering questions — at least at this conference. He canceled his Thursday talk.