David Cyranoski and Sarah Reardon report:
In a world first, Chinese scientists have reported editing the genomes of human embryos. The results are published1 in the online journal Protein & Cell and confirm widespread rumours that such experiments had been conducted—rumours that sparked a high-profile debate last month about the ethical implications of such work.
In the paper, researchers led by Junjiu Huang, a gene-function researcher at Sun Yat-sen University in Guangzhou, tried to head off such concerns by using ‘non-viable’ embryos, which cannot result in a live birth, that were obtained from local fertility clinics. The team attempted to modify the gene responsible for β-thalassaemia, a potentially fatal blood disorder, using a gene-editing technique known as CRISPR/Cas9. The researchers say that their results reveal serious obstacles to using the method in medical applications.
“I believe this is the first report of CRISPR/Cas9 applied to human pre-implantation embryos and as such the study is a landmark, as well as a cautionary tale,” says George Daley, a stem-cell biologist at Harvard Medical School in Boston. “Their study should be a stern warning to any practitioner who thinks the technology is ready for testing to eradicate disease genes.”
There were too many off-target mutations, but the Chinese attitude seems to be if at first you don’t succeed…
…there are reports that other groups in China are also experimenting on human embryos.
The article is interesting throughout, for instance:
Huang says that the paper was rejected by Nature and Science, in part because of ethical objections; both journals declined to comment on the claim (Nature’s news team is editorially independent of its research editorial team.)