China’s CRISPR baby saga continues to rage on. After the birth of gene-edited twins in China last year, and the reported pregnancy of a second woman, the world’s scientific community voiced their shock at what sounds (provided it’s accurate) like an ethical nightmare. Now scientists have expressed concerns that the procedure may also have resulted in changes in the babies’ brains that could affect cognition and memory.
The genetic modifications were intended to eliminate a gene called CCR5, thought to be responsible for potentially fatal diseases including HIV, smallpox, and cholera. A newly published research paper in the journal Cell suggests that CCR5 manipulation can additionally lead to enhanced recovery after brain injury, including motor recovery following strokes. While this has only been demonstrated (outside of China) in mouse models, the findings could conceivably be applicable in human subjects. It is not clear whether Chinese researcher He Jiankui was trying to modify the intelligence of his subjects with his controversial experimentation.
But why, if the changes are positive, is this such a bad thing? Principally, for the same reasons that the news shocked scientists when it was first announced. Human testing of such unproven treatments is deeply unethical, and carries an extremely high risk. Data submitted as part of the trial (for which the lead scientist has now been sacked from his associated university) indicated that genetic testing has been conducted on fetuses as old as six months.
“We simply do not know enough to predict what would happen in a normal brain if someone were to try to enhance cognitive function by changing the genes at work in the brain,” Alcino J. Silva, a neurobiologist at the University of California, Los Angeles, who carried out the CCR5 mouse research, told Digital Trends. “Unintended consequences are one of the sad and common results when people, even with good intentions, start mucking around with serious things we simply do not understand well enough.”
Silva added that he “would not be surprised if the enhancements we saw in memory occur in parallel with deficits in other aspects of cognitive function or under other conditions that we did not test.”
At some point in the future, drugs and other treatments can be developed to take advantage of this research. That could well include a large number of cognitive deficits associated with a range of conditions from Alzheimer’s disease to depression. But irresponsible experiments like the one carried out by He Jiankui are not the way to go about achieving this.