He Jiankui, a scientist and professor of biology at the Southern University of Science and Technology (SUSTech) in Shenzhen, Guangdong, China, has proclaimed the births of Nana and Lulu, the world’s first gene-edited babies. While this claim remains unverified by a third party, He posted a video to YouTube claiming that the genetic alterations were verified and that Nana and Lulu were healthy.

He’s claim has drawn a great deal of international criticism due to the fact that human genome editing has not been proven to be safe, and acceptable ethical guidelines have yet to be fully drafted or agreed upon. Genomic editing in viable human embryos is banned to various degrees in many countries.

In China, however, there are no clear laws in place to prevent these actions, only guidelines. He’s claims highlight the immediate need to develop strong international agreements on the ethical use of human genome editing, and the necessity of strong legal frameworks surrounding what modifications, if any, are permitted.

Editing genes in human embryos

Lulu and Nana are purported to have had their CCR5 gene removed, which is thought to endow immunity to HIV infection. He Jiankui recruited couples where one parent was HIV-positive in the hopes of eliminating the passing of the virus from the parent couple to newborn children. If He was successful in genetically modifying Lulu and Nana, it will represent a significant medical breakthrough.

Through editing genes in viable human embryos, it will be possible to prevent newborns from acquiring a wide range of both genetic and microbiological diseases. He’s group made use of CRISRP-cas9 gene-editing technology to edit Lulu and Nana’s genomes, but the use of this technique may have broader safety concerns, as recent investigations by Kosicki, Tomberg and Bradley have revealed that CRISPR is capable of producing large unintended genetic alterations that may carry negative health consequences to genetically altered individuals.

This form of genetic modification, which He claims to have performed at the embryonic single-cell stage, means that any alterations will be inherited by future offspring. The heritability of these genetic alterations places extra emphasis on the unknown safety concerns of CRISPR gene editing technology and may have implications far beyond Lulu and Nana themselves.

CRISPR babies ethics: moving forward

Bioethics committees in several countries, such as the Nuffield Council on Bioethics in the UK and the National Academy of Sciences in the US, have been slowly warming to the idea of genetically modifying human babies in cases where serious disease can be prevented. Although there is an increasing trend of support for genetic modifications in humans, a stringent and highly cautious approach is universally called for.

Amid the firestorm of criticism and investigations into the work that He’s group has announced, it is vital that the international community come together and formulate a framework as to what is acceptable in the field of human genetic modification, as work like this has serious implications in the spheres of global medical research, biomedical technology, and the human gene pool itself.