According to an earlier report by American researchers, the deletion of that particular gene not only makes mice smarter but also improves human brain recovery after stroke. The report noted that such enhancements could be linked to greater success in school. “The answer is likely yes, it did affect their brains,” said Alcino J. Silva, a neurobiologist at the University of California, Los Angeles.
Silva’s laboratory discovered a major new role for the CCR5 gene in memory and the brain’s ability to form new connections, reports the MIT Technology Review. “The simplest interpretation is that those mutations will probably have an impact on cognitive function in the twins,” Silva said.
He further noted that it is impossible to predict the exact effect on the girls’ cognition, so he suggests that “it should not be done.”
The Chinese team, which claimed to have successfully deleted CCR5 from human embryos usingCRISPR genome editing in November last year.
The experiment sparked controversy, with many in the scientific community condemning it as irresponsible. He, the lead researcher, remains under investigation in China.
While there is no evidence that He may have intentionally set out to modify the twins’ intelligence, he may have already been aware of the link between CCR5 and cognition prior to their experiment.
As MIT Technology Review pointed out, the link was already shown in 2016 by Western University of Health Sciences Miou Zhou and Silva.
After looking at over 140 different genetic alterations to find which made mice smarter, the study determined that removing the CCR5 gene from mice improved their memory significantly.
According to Silva, when he learned about the birth of the twins on November 25, he immediately wondered if it had been an attempt at making them smarter. “I suddenly realized—Oh, holy shit, they are really serious about this bullshit,” Silva was quoted as saying. “My reaction was visceral repulsion and sadness.”
“Could it be conceivable that at one point in the future we could increase the average IQ of the population? I would not be a scientist if I said no. The work in mice demonstrates the answer may be yes,” Silva says. “But mice are not people. We simply don’t know what the consequences will be in mucking around. We are not ready for it yet.”
Based on the recent findings, CCR5 acts as a suppressor of memories and synaptic connections, revealing that people who naturally lack CCR5 recover from strokes much faster.
The report, published in the journal Cell, also posits that people without at least one copy of the gene appears to do better in school.
UCLA biologist S. Thomas Carmichael, who led the new study, noted that while the link to educational success was “tantalizing,” he admits that it needs further study.
He Jiankui actually acknowledged knowing the potential brain effects revealed from the UCLA research during a summit of gene editing scientists. “I saw that paper, it needs more independent verification,” He Jiankui was quoted as saying. “I am against using genome editing for enhancement.”