- A Chinese researcher claims to have successfully edited the DNA of twin girls born earlier this month in what would be, if verified, a remarkable and highly controversial milestone for the science of gene editing.
- According to reports from MIT Technology Review and AP, He Jiankui of the Southern University of Science and Technology used CRISPR/Cas9 to alter embryos from seven Chinese couples during fertilization treatment. The twin girls are the first birth to result, the AP reported.
- He's team seeks to use the gene editing technique to disable a gene known as CCR5. People without a functioning copy of the gene are known to be resistant to HIV infection. News of He's announcement will likely spur significant criticism, as human gene editing research remains in early stages and changes made to embryonic DNA can be inherited.
He's announcement, if true, would mark a significant acceleration of human gene editing research. The research has yet to be published in academic literature, nor has it been peer reviewed to determine the accuracy of He's claim.
In the U.S., using a genetically edited embryo to begin a pregnancy is banned and the legal grounds for such work is unclear even in China, notes MIT Technology Review.
So far, scientists have aimed to use CRISPR/Cas9 to treat — or hopefully cure — genetic diseases in adults. The first company-sponsored study of the technology in humans was just recently given the go-ahead to proceed in the U.S. by the Food and Drug Administration, while U.S. academic research is progressing in parallel.
By comparison, the pace of research has been quicker in China, with human studies in adults already begun.
Using CRISPR/Cas9 in embryos, though, spurs ethical questions about whether the technology — and science's understanding of its applications and implications — is mature enough to rewrite the genetic makeup of babies.
For one, changes made to germline DNA can be inherited by future offspring of the genetically altered child. Concerns over so-called off-target editing remain as well, although He has said tests done on the embryo before implantation and after birth revealed no other genes were inadvertently changed.
He also apparently did his research without informing his employer or other academic groups.
"The University was deeply shocked by this event and has taken immediate action to reach Dr. Jiankui He for clarification," wrote the Southern University of Science and Technology in a statement released Monday.
In its statement, the university noted He, who has been on unpaid leave since February 2018, conducted his research outside of the institution.
More critically, the school said He's use of CRISPR/Cas9 gene editing to alter human embryos "seriously violated academic ethics and codes of conduct."
He appeared to be aware of how controversial his announcement would be. In a series of videos apparently posted by He to YouTube on Sunday, the researcher defended his work and pushed back against expected criticism.
"Their parents don't want a designer baby," He said in one video. "Gene surgery is, and should remain, a technology for healing."
He's choice of editing the CCR5 gene could also spark questions, the AP notes in its report. While people without a functional copy of the gene are less likely to contract HIV, such individuals are at higher risk of other viruses such as West Nile and the flu, the AP wrote.
Editing CCR5 to lower the risk of HIV is also preventative, rather than aimed at curing an already present genetic defect.
"Assuming that independent analysis confirms today’s news, this work reinforces the urgent need to confine the use of gene editing in human embryos to settings where a clear unmet medical need exists, and where no other medical approach is a viable option, as recommended by the National Academy of Sciences," said Jennifer Doudna, a noted pioneer in CRISPR/Cas9 research, in a statement released by the University of California, Berkeley.
Feng Zhang, a researcher at the Broad Institute who's also been at the center of CRISPR development, went further.
"Given the current early state of genome editing 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," Zhang said in a statement issued by the Broad.
He's announcement came ahead of the Second International Summit on Human Genome Editing, set to begin Tuesday in Hong Kong. He is scheduled to speak at the conference Wednesday.