CRISPR Co-Inventor Feng Zhang's Full Statement: Gene-Edited Babies Are Not Only Dangerous

Recently, a report that a Chinese researcher claimed in an exclusive interview with the Associated Press that his laboratory had used CRISPR to create twin girls has shocked the world, causing an uproar among academic circles and the general public worldwide.

Following the emergence of this news, CRISPR co-inventors Feng Zhang and Jennifer Doudna issued separate statements urging caution and calling for a moratorium on gene editing in human embryos.

In a statement submitted to MIT Technology Review, Zhang Feng stated, “Given the current state of technology, I support a moratorium on the implantation of edited embryos.”

"In this trial, Chinese researchers edited human embryos to remove a gene called CCR5. However, the study was conducted in secret, and medical experts have questioned whether it was necessary or safe."

Feng Zhang believes that the risks of this trial outweigh the benefits, expressing “deep concern” that the project in China is being conducted in secret. He called for a “comprehensive moratorium on implanting edited embryos … until we first develop a set of carefully considered safety requirements.”

In a statement, Doudna said, “This Chinese CRISPR experiment has not yet been validated in peer-reviewed journals. However, if the experiment is confirmed, scientists should limit the use of human embryo gene editing to cases where there are clear unmet medical needs and no other viable medical alternatives.”

The concerns of Zhang Feng and Doudna reflect those of many scientists and bioethicists that China’s experiments lack transparency and that standards for gene editing should be established before altering the DNA of infants.

Previously, authoritative academic institutions, including the National Academy of Sciences, stated that gene-edited children should only be produced under strict safety and regulatory conditions.

Below is Zhang Feng’s full statement:

Although I appreciate the global threat posed by HIV, at this stage, the risks of editing embryos to knock out CCR5 seem to outweigh the potential benefits, not to mention that knocking out of CCR5 will likely render a person much more susceptible for West Nile Virus. Just as important, there are already common and highly-effective methods to prevent transmission of HIV from a parent to an unborn child.

Although I recognize the threat that HIV poses globally, at this stage, the risks of editing embryos to knock out CCR5 appear to outweigh the potential benefits, not to mention that CCR5 knockout may increase an individual’s susceptibility to West Nile virus infection. Equally important is the fact that there are already widespread and effective methods to prevent mother-to-child transmission of HIV.

Given the current state of the technology, I’m in favor of a moratorium on implantation of edited embryos, which seems to be the intention of the CCR5 trial, until we have come up with a thoughtful set of safety requirements first.

Given the current state of technology, I support a moratorium on the implantation of edited embryos (which appears to have been the intent of the CCR5 trial) until we first establish a set of carefully considered safety requirements.

Not only do I see this as risky, but I am also deeply concerned about the lack of transparency surrounding this trial. All medical advances, gene editing or otherwise and particularly those that impact vulnerable populations, should be cautiously and thoughtfully tested, discussed openly with patients, physicians, scientists, and other community members, and implemented in an equitable way.

I believe this is not only dangerous, but I am also deeply concerned about the lack of transparency in this trial. All medical advances, whether in gene editing or other fields—especially those affecting vulnerable populations—should undergo rigorous and thoughtful testing, be openly discussed with patients, physicians, scientists, and other community members, and be implemented in an equitable manner.

In 2015, the international research community said it would be irresponsible to proceed with any germline editing without “broad societal consensus about the appropriateness of the proposed application.” (This was the consensus statement from the 2015 International Summit on Human Gene Editing.)

In 2015, the international research community stated that any human embryo gene editing conducted “in the absence of broad social consensus on the appropriateness of its application” would be irresponsible. (This was from the consensus statement of the 2015 International Summit on Human Gene Editing.)

It is my hope that the upcoming summit will serve as a forum for deeper conversations about the implications of this news and provide guidance on how we as a global society can best benefit from gene editing.

I hope that the upcoming summit will serve as a forum for more in-depth discussions on the implications of this development, and provide guidance on how we, as a global society, can maximize the benefits of gene editing.

This article concludes with a statement from Wang Liming, a Chinese biologist and author of *God’s Scalpel*:

“At a time when this technology remains fraught with unknown risks, conducting research on healthy, risk-free human individuals—research that is highly likely to introduce unintended risks while offering virtually no health benefits—is not only unscientific but also unethical, constituting a violation of human dignity and the spirit of scientific inquiry.”

This article is reposted from the WeChat official account: MedPartner, by Tara TIAN