(CNN) As 2018 drew to a close, one scientist unveiled research that entered a new era of science. But it soon prompted extensive backlash from around the globe.

Chinese scientist He Jiankui announced in November that he had created the first gene-edited babies, twin girls whose DNA had been edited using the CRISPR-Cas9 tool to protect them from HIV.

Editing the DNA of human embryos had never been done before, for good reason, and the scientist went against the advice of experts in the field to conduct the work, which could lead to a multitude of unknown genetic complications for the children.

Everyone he talked to -- which was not many people -- had said "don't go there," "don't do it," explained Robin Lovell-Badge of the UK research facility the Francis Crick Institute, who organized the scientific summit in Hong Kong during which the news broke in November. "He had already been told not to proceed," he said.

The announcement came on the eve of this summit, the Second International Summit on Human Genome Editing. Two days later, He defended his work on the scientific stage and announced that a second pregnancy using the technology was underway.

Then He went into hiding, having received threats, explained Lovell-Badge, who provided new detail of the events Monday. His last contact with the Chinese scientist was on December 1.

Before the meeting, "it was clear that we was up to something," Lovell-Badge said, explaining that there had been rumors that He was seeking local ethical approval to edit the embryos. This was why He was invited to attend and speak at the conference: to get him around peers and calm his ambition.

"None of us knew how far he'd actually got," Lovell-Badge said, adding that experts knew only of his research on mice, monkeys and human embryos. "Clearly, we were too late."

However, the babies have not been independently confirmed, and the hospital named as approving the research has denied being associated with the scientist.

Lovell-Badge believes that He is in an apartment in Shenzhen, surrounded by guards, and said he is unclear whether the guards are there to restrict him or protect him.

He Jiankui, center, with Robin Lovell-Badge, head of the Laboratory of Stem Cell Biology and Developmental Genetics at the Francis Crick Institute, left, at the Second International Summit on Human Genome Editing.

Rich, egotistical and disrespectful of guidelines

He made a lot of money selling companies, Lovell-Badge said, which enabled him to fund the research himself, and therefore no funding body validated his work.

"He was very rich," he said, and "treated very well by the Chinese system," which encouraged his return to the country after he trained as a physicist in the United States.

Lovell-Badge summarized the scientist as a rich physicist who knew little biology, with a huge ego, someone who wants to be the first to do something he believes will change the world, irrespective of any guidelines.

He knew about guidelines not to implant a genetically altered embryo, "but he went ahead anyway" and was "doing it in secret, largely."

The scientist consistently believed that he was doing good, Lovell-Badge explained, but the science and his ethics were flawed.

For example, He did not know enough about the mutation he was trying to introduce into the babies -- known as Delta 32 -- which was intended to protect the girls from HIV but could also increase the risk of West Nile virus and influenza, previous research had shown. He had told Lovell-Badge on stage at the conference that he was aware of the rise in risk of those two diseases but believed that the risk of West Nile virus not an issue in China and claiming that the influenza research had been flawed. However, a few days later, He asked Lovell-Badge for more information on the influenza link.

Lovell-Badge believes the babies' families were not informed of the influenza link when giving their consent to He, despite the virus being a huge risk in China. "It's quite possible he has put the children at risk," he said, adding to the unethical point that the scientist obtained consent himself, rather than through an impartial third party.

In addition, there are effective ways to prevent HIV from being passed from parents to children, meaning the controversial research did not even have an "unmet clinical need," Lovell-Badge said. But the stigma around HIV in China seemed to be what drove the Chinese scientist, he said.

'I'm pretty sure he's done it'

A big question looming over the series of events is whether these gene-edited babies truly exist, with no proof of their existence and no peer-reviewed research on He's work. It's simply his word.

His work on mice and monkeys had been presented at conferences, however, Lovell-Badge explained, and He had told the Summit about submitting a paper on the gene-edited babies for review to a reputable scientific journal. Where that paper is now remains a mystery, however.

The flaws in his approach also make Lovell-Badge believe that the babies are real. "If he was going to make this up, he would have made it up much better than this," he said. "I'm pretty sure he's done it." The only real way to know is to test the DNA of the babies, which he believes Chinese authorities will ensure as part of their investigations.

In addition, He had a US PR person at his side, Ryan Ferrell, who advised him to create videos explaining his news to post on YouTube as well as to provide access to the Associated Press to follow his work, all for a big unveiling, probably in 2019.

But the order of play was interrupted by the MIT Technology Review , which caught wind of the work and reported on it, making the news global as the Hong Kong summit was due to begin, Lovell-Badge said. Chaos ensued. "He hadn't planned to hijack the meeting."

'There is a place' for gene editing

Lovell-Badge believes that He will be punished and locked up or fined as Chinese authorities conclude their investigation and that many people involved will lose their jobs. He also fears for the future of the babies, who may have their fate, and future reproduction, controlled.

As for the field as a whole, Lovell-Badge said, discussions began in 2015 on the need for a pathway for scientists to follow in order to show certain stages of research before finally editing embryos, with more need for this now than ever.

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Clear laws need to be in place, he said, as many countries -- except the UK and the United States -- have guidelines but not clear outlines for laws and resulting punishments if such research is conducted, paving the way for a maverick scientist like He.

The Chinese hospital named in He's ethical approval documents, Shenzhen Harmonicare Women's and Children's Hospital, denies involvement in the procedures. "We can ensure that the research wasn't conducted in our hospital nor were the babies born here," a hospital representative told CNN earlier. Initial investigations by the hospital said that signatures on He's ethics review form are suspected to be forged.

But "properly done, there is a place for genome germline editing," Lovell-Badge believes, with the germline being the genes and cells passed down through generations. Editing could target diseases with a true clinical need, he said, such as cystic fibrosis or the blood disorder beta-thalassemia.

What there is no place for: scientists simply on a mission to be the first to do something. "He should certainly be stopped from doing anything like this again."