Second Chinese team reports gene editing in human embryos

Researchers in China have reported editing the genes of human embryos to try to make them resistant to HIV infection. Their paper1— which used CRISPR-editing tools in non-viable embryos that were destroyed after three days — is only the second published claim of gene editing in human embryos.

In April 2015, a different China-based team announced that they had modified a gene linked to a blood disease in human embryos (which were also not viable, and so could not have resulted in a live birth). That report — a world first — fuelled global deliberations over the ethics of modifying embryos and human reproductive cells, and led to calls for a moratorium on even such proof-of-principle research.

At the time, rumours swirled that other teams had conducted similar experiments. Sources in China told Nature’s news team that a handful of papers had been submitted for publication. The latest paper, which appeared in the Journal of Assisted Reproduction and Genetics on 6 April, might be one of these. Nature’snews team has asked the paper’s corresponding...