Researcher Denis Rebrikov’s plan is to reduce the risk of transmission of the HIV virus to the baby in the womb: the first experience of the type occurred in 2018 in China
Molecular biologist Denis Rebrikov says he intends to edit the genes of human babies and put their experiments into practice by the end of this year. To continue planning to inseminate modified embryos in women, it must receive government permission, as stated in the journal Nature.
Rebrikov would follow in the footsteps of Chinese scientist He Jiankui, responsible for announcing in November 2018 that he generated the first genetically modified babies.
Rebrikok says his experiment will target the same gene used by Jiankui, the so-called CCR5. But Rebrikov says his technique will offer greater benefits, pose fewer risks and be more ethically justifiable and acceptable to the public.
The Russian biologist runs a genome-editing laboratory at Russia’s largest fertility clinic, the Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology in Moscow, and is a researcher at the Russian Research University of Pirogov, also in Moscow.
He says he plans to deactivate the gene that encodes a protein that allows HIV to enter cells in embryos that will be implanted in HIV-positive mothers, reducing the risk of transmitting the virus to the baby in the uterus.
According to Rebrikov, he already has an agreement with an HIV center in the city to recruit HIV-infected women who want to participate in the experiment.
Nature contacted scientists and bioethicists contacted to hear their views on Rebrikov’s plan. “The technology is not ready,” says Jennifer Doudna, a molecular biologist at the University of California at Berkeley, who pioneered the CRISPR-Cas9 genome-editing system that Rebrikov plans to use.
Already, Alta Charo, a researcher in bioethics and law at the University of Wisconsin-Madison, says Rebrikov’s plans are not an ethical use of technology. “It is irresponsible to proceed with this protocol at this time,” adds Charo, who participates in a committee of the World Health Organization that is formulating policies of ethical governance for editing the human genome.
The biologist finds another challenge in his project since the implantation of genetically modified embryos is prohibited in many countries. In the case of Russia, there is a law that bans genetic engineering in most circumstances, but it is not clear whether or how the rules would be applied in relation to gene editing in an embryo.
Rebrikov says he hopes the Health Ministry will clarify the rules on the clinical use of embryo genetic editing in the next nine months and that it feels a sense of urgency to help women with the HIV virus.
One reason why genetically engineered embryos have created a huge global debate is that, if allowed to be transformed into babies, issues can be passed on to future generations – a long-range intervention is known as germline alteration.
The researchers agree that the technology may one day help eliminate genetic diseases such as sickle cell anemia and cystic fibrosis, but much more testing is needed before it is used in humans.
Rebrikov says he plans to deploy embryos only in a subset of HIV-positive mothers who do not respond to anti-HIV drugs, where the risk of transmitting the infection to the child is greater.
If the issue successfully disables the CCR5 gene, that risk would be greatly reduced, says the Russian researcher. “This is a clinical situation that requires this kind of therapy,” he says.
Still, most scientists say there is no justification for editing the CCR5 gene in embryos because the risks do not outweigh the benefits.
Even if the therapy is as planned, and both copies of the CCR5 gene in the cells are turned off, there is still a chance that these babies will become infected with HIV.
It is believed that the cell surface protein encoded by CCR5 is the gateway to about 90% of HIV infections, but getting rid of it will not affect other routes of HIV infection.