Scientists are reacting to news that Chinese researchers have conducted germline gene editing on humans by calling the work immoral and premature and saying the technology remains far from useful for clinical applications for human germlines.
In a study published in Protein & Cell yesterday, the researchers from SunYat-sen University in Guangzhou, China used the CRISPR/Cas9 method to edit non-viable human zygotes to modify the gene that causes the hereditary blood disease beta-thalassemia. Reaction from the scientific community was swift, and in many cases, condemning.
"No researcher should have the moral warrant to flout the globally widespread policy agreement against modifying the human germline," Marcy Darnovsky of the Center for Genetics and Society, says in an email to NPR's Shots. "This paper demonstrates the enormous safety risks that any such attempt would entail and underlines the urgency of working to forestall other such efforts. The social dangers of creating genetically modified human beings cannot be overstated."
To be fair, the Chinese research falls short of opening the door to genetic "designer babies," as the scientists report several problems, including missing targets with their method and inserting DNA in the wrong places. The researchers acknowledge in their study that "clinical applications of the CRISPR system may be premature at this stage."
Jennifer Doudna from the University of California, Berkeley and a co-founder of the CRISPR/Cas9 technology tells National Geographic in an email, "Although it has attracted a lot of attention, the study simply underscores the point that the technology is not ready for clinical application in the human germline. And that application of the technology needs to be on hold pending a broader societal discussion of the scientific and ethical issues surrounding such use."
Rumors about the use of CRISPR/Cas9 editing on human germlines had been floating around for some while, and in March scientists, including Doudna, expressed their concern in an editorial in Science about the possible unethical use of the technology.
As the Sun Yat-sen team tried to get its work published, they also encountered resistance due to ethical concerns, Nature News reports. Both Nature and Science passed on running the study partly because of ethical objections.
King's College stem cell researcher Dusko Ilic, however, says that despite any concerns raised by the Protein & Cell paper, genetic editing in human applications is almost a certainty in the future.
"You cannot stop science," he tells The Guardian. "No matter what moratorium is proposed, you cannot stop this work continuing around the world."
He also pooh-poohs any notion that the Chinese research is unethical, saying the embryos used in the work had been fertilized by two sperm and would have been thrown out by any in vitro fertilization clinic anywhere. "There is no ethical objection you can bring," Ilic says.