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The CRISPR gene-edited babies: a technological breakthrough or a brave new future?


Written by Adam Amara

He Jiankui announcing the birth of the gene-edited twins on Youtube

The announcement of the first CRISPR gene-edited babies has sparked a major polemic in the scientific community, but also in the media and the public. The research was discreetly carried by a Chinese team lead by He Jiankui at the Southern University of Science and Technology (SUST), in Shenzhen. He announced in a Youtube video: “Two beautiful little Chinese girls, Lulu and Nana, came crying into the world as healthy as any other babies a few weeks ago”. The research team have used CRISPR to deactivate the CCR5 gene in the embryos, which were then implanted into the mother. The CCR5 gene encodes for a protein that enables the HIV virus to enter in human cells. The aim was to deactivate it to reduce the risk of HIV infection, as the father was HIV-positive. This procedure has been apparently applied to eight couples. However, its success is still unclear, as no data or details were publicly released yet.


Deletion/insertion in genome by CRISPR Source: Wikimedia

In response to this announcement, many researchers in China and abroad condemned this experiment. Feng Zeng, the pioneer researcher in the application of CRISPR in mammalian cells, called for a global moratorium. Feng insisted that he was “deeply concerned” of the fact that the project was secretly undertaken. More than a 100 Chinese scientists have also signed a letter condemning the experiment. This announcement also coincides with the Second International Summit on Human Genome Editing in Honk Kong, where many researchers reiterated the condemnations against the experiment. It was highlighted by Qiu Renzong (Chinese Academy of Social Science) that this violates the regulation in China, which is however not penalized. In opposition, George Church (Harvard University) defended it saying that HIV was “a major and growing public health threat” and “I think this is justifiable”.


The whole story is not fully known yet, and we still need to wait a few days to have more information to find out how the experiment was conducted. However, this story puts at risk the near future of gene editing, due to the way it was carried, with the secrecy around the project and the non-respect of ethical procedures.


Off-target effects of CRISPR Source: Wikimedia

At first, the issues with off targets in CRISPR gene-editing means that there are still high risks of inducing unwanted modifications in the genome. So, the babies risk irreversible damage in their genomes, potentially transmitting these to their offspring. Secondly, the way the team carried this experiment creates multiple ethical and practical issues. If the public see that scientists can decide to “engineer babies” in secret without any safety check, we risk to end up banning or restricting CRISPR even more. From an ethical point of view, using CRISPR was not a last resort solution here; other safer options exist to avoid HIV transmission from parents to their children. In practice, the cost of an IVF is not accessible to the vulnerable populations where HIV spreads. The CCR5 gene was probably an “easy” target, giving the opportunity to be the first one in the race to apply CRISPR in humans. But, the attention that this story attracts can negatively impact the public (and policy-makers’) perception of scientists and CRISPR. If the technology lacks a wide public understanding and support, it could delay the release of validated lifesaving treatments for many years.


Even if one day humanity decides to modify itself to prevent diseases, it is still too early and it is not the choice of a single person or a small group of academics. In the end, as scientists, we should do our best to bring life changing solutions, like human gene-editing, in a responsible way to make sure of the best positive impact possible.

“All conditioning aims at that: making people like their unescapable social destiny”

Aldous Huxley, Brave New World


Adam Amara is a PhD student at the University of Manchester and EUSynBioS steering committee member.


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