The world's first "gene-edited" babies, a set of girl twins whose embryonic genes were altered by a technology known as CRISPR-Cas9 to make them immune to infection by HIV, could have an enhanced ability to learn and form memories, reports MIT Review.
Chinese scientist He Jiankui said in November that he used CRISPR to remove a gene called CCR5. The deletion does not only eliminate the threat of contracting HIV, which causes AIDS, but makes mice smarter and improves human brain recovery after stroke.
"The answer is likely, yes, it did affect their brains," Alcino J. Silva, a neurobiologist at the University of California, Los Angeles, told MIT Review.
"The simplest interpretation is that those mutations will probably have an impact on cognitive function in the twins" he added.
Hundreds of Chinese and international scientists condemned him and said any application of gene editing on human embryos for reproductive purposes was unethical. Chinese authorities also denounced him and issued a temporary halt to research activities involving the editing of human genes.
The CCR5 gene has been the subject of research since the 1990s, and studies have shown its presence helps to protect the lungs, liver, and brain during some other chronic diseases and serious infections.
Silva and Miou Zhou, a professor at the Western University of Health Sciences in California, published a paper in 2016 stating that removing CCR5 from mice significantly improved their memory.
Additionally, Silva says he and a large team from the U.S. and Israel say they have evidence the gene acts as a suppressor of memories and synaptic connections and people who lack it seem to go further in school.