Official Statement from CSCB & GSC

Condemning the reproductive application of gene editing on human germline

Chinese Society for Stem Cell Research, CSCB

Committee of Genome Editing, Genetics Society of China

Nov. 27th, 2018

On Nov. 26th, 2018, Jiankui He, associate professor from Southern University of Science and Technology, announced that two babies with edited CCR5 gene have been born in China, and he believed that this genetic modification would render these babies immune to HIV infection. While more solid facts of this experiment remain to be disclosed and the veracity of such claims are yet to be ascertained, we strongly condemn any application of gene editing on human embryos for reproductive purposes. Such intervention is against the law, regulation, and medical ethics of China. Moreover, it violates internationally accepted ethical principles regulating human experimentation and human rights law.

Originally discovered as a prokaryotic immune system, CRISPR/Cas has become the tool of choice for editing genome of various species, providing invaluable resources for biology and biotechnology development. While gene editing technology has been improved significantly over the past years, the relatively low efficiency on precise modification and potential off-target mutations remain a major concern. On the first international gene editing summit, held in Washington in 2015, co-sponsored by the Chinese Academy of Sciences, scientists from all over the world had comprehensive discussion about the technology, ethics, and regulation issues of gene editing, and reached a very clear consensus: gene editing of human germline should not be conducted for reproductive purpose at current status.

China has strict regulations on experimental procedures related to human embryos that mirror regulations adopted around the world. In 2003, the Ministry of Science and Technology and the Ministry of Health published the “Ethical principles of research on human embryonic stem cells”, which clearly stated “human embryos used in research are not allowed to be implanted into uterus of human or other animals”. In the same year, the Ministry of Health published “Technical guidelines, basic standards, and ethical principles on human assisted reproductive technology and sperm bank”, in which “any genetic modification on human germ cells, zygotes, and embryos are strictly forbidden” is unambiguously stated. The more recent document “Regulation of human genetic resources” published by the Ministry of Science and Technology in 2017 listed “human gene editing research with high risk” as the highest risk level, asking all entities to regulate related research with the highest care and attention to the internationally accepted ethical standards. Chinese scientists working in the gene editing field have also had many extensive discussions on scientific and ethical issues related to gene editing, and reached a clear consensus that any clinical application of gene editing for reproductive purpose should be strictly forbidden in China.  

Based on currently available information, we believe the research led by He is strongly against both the Chinese regulations and the consensus reached by the international science community. We strongly condemn it for the extreme irresponsibility, both scientifically and ethically. Just to point out a few issues out of many, it is uncertain whether knocking out CCR5 would ensure the health of the baby. Loss of CCR5 function in Chinese genetic background has never been proven to be safe, and the potential negative effect is almost impossible to predict. From a technical perspective, the potential off-target mutation and mosaicism have not been completely solved, which are often resulted from zygote gene editing. From an ethical perspective, knocking out CCR5 gene from a genetically normal zygote would not provide much benefit because the baby could have been kept from being exposed to HIV infection. There is no sound reason to perform this editing. The best interest of the child should always be paramount.

With CRISPR/Cas and other genome engineering technologies emerging in an unprecedented speed, the technical barrier of changing genetic information of any species in this planet becomes increasingly low. This requires all scientific researchers to strictly follow the regulations of their nations, and respect the basic human ethical principles. As the scientists working on gene editing or stem cell research, before solving the relevant safety and efficacy issues and reaching broad scientific and social consensus, we are strongly against the clinical application of gene editing on human germ line for reproductive purpose. We strongly appeal for all gene editing researchers in China to strictly follow Chinese regulations to nurture a healthy environment for science and technology development.  

Representing the science community working on gene editing and stem cells research, we make the following statement: the experiment conducted by He’s group is an individual behavior. We believe it poses tremendous safety risk for the research subjects, and this misconduct is against the current Chinese regulations and internationally accepted ethical guidelines that China endorses. It also poses significant implications for human society as a whole. We strongly condemn this conduct and suggest all related research entities and government bureaus to initiate official investigations.