Gene-edited Chinese babies may have ‘enhanced brains’ scientists say

New research suggests changes to gene in twins may have had unintended consequences

The world’s first gene edited babies may have had their brains unintentionally altered – and perhaps cognitively enhanced – as a result of the controversial treatment undertaken by a team of Chinese scientists.

Dr He Jiankui and his team allegedly deleted a gene from a number of human embryos before implanting them in their mothers, a move greeted with horror by the global scientific community. The only known successful birth so far is the case of twin girls Nana and Lulu.

The now disgraced scientist claimed that he removed a gene called CCR5 from their embroyos in an effort to make the twins resistant to infection by HIV.

But another twist in the saga has now emerged after a new paper provided more evidence that the impact of CCR5 deletion reaches far beyond protection against dangerous viruses – people who naturally lack this gene appear to recover more quickly from strokes, and even go further in school.

This followed previous experiments that found removing the gene significantly improved the memory of mice.

Dr Alcino Silva, a neurobiologist at the University of California, Los Angeles, who helped identify this role for CCR5 said the work undertaken by Dr Jiankui likely did change the girls’ brains.

“The simplest interpretation is that those mutations will probably have an impact on cognitive function in the twins,” he told the MIT Technology Review.

The connection immediately raised concerns that the gene was targeted due to its known links with intelligence, which Dr Silva said was his immediate response when he heard the news.

“I suddenly realized – oh, holy s***, they are really serious about this bulls***… My reaction was visceral repulsion and sadness.”

However, there is no evidence that this was Dr Jiankui's goal and at a press conference organised after the initial news broke, he said he was aware of the work but was “against using genome editing for enhancement”.

Dr Silva noted that while there may well have been changes to the girls' brains, changes to their intelligence would be impossible to predict.

“That is why it should not be done”, he said, noting that people are “not ready” for attempts to genetically alter the IQ of the population.

Some scientists however hope that the new research could inform work on drugs to treat strokes and memory problems.

Professor Robin Lovell-Badge, who organised the meeting at which the scandal first emerged, told The Independent the new findings were “very interesting” but should be approached with caution in the context of the gene edited twins.

He suggested that the CCR5 changes made in the human embryos differed slightly to the ones performed in previous experiments, adding that the information that has been released shows a significant number of their cells will not contain the mutation at all.

Any changes to the brains of the two girls may therefore never become apparent, Mr Lovell-Badge said.

“I hope that Nana and Lulu and eventually any children they have, will be left alone,

"They are just normal little girls, who happen to have unusual mutations in CCR5 in some of their cells. If these had arisen by chance, we would probably never have known and would not care.”