In a controversial move, Britain’s Human Fertilisation and Embryology Authority (HFEA) regulatory body has approved a research application for a London-based laboratory to carry out gene-editing experiments on human embryos. While the proposed experiments are aimed at researching fertility issues, critics of the issue say that this could open the door to creating designer babies.

This decision comes in the wake of the news from last April of a Chinese research team that conducted similar research, editing the genes of human embryos to study β-thalassaemia, a potentially fatal blood disease. This new study, to be conducted by the Francis Crick Institute in London, "will be for research purposes and will look at the first seven days of a fertilized egg’s development, from a single cell to around 250 cells," according to the lab.

The research will make use of the already-controversial CRISPR-Cas9 gene-editing technique: this method uses a gene-editing technique naturally used by many species of bacteria, as a defense against invading viruses. CRISPR-Cas9 allows researchers to remove certain portions of the DNA strand, and replace it with one of their choosing.

The Institute says that the research will be focused on how human embryos develop during the first week of development, a period when there is a great deal of genetic activity in the cluster of cells. The individual embryos will be terminated after the previously-mentioned 7-day growth period.

The stem-cell researcher leading the research, Kathy Niakan, hopes that the data gathered will help them understand human fertility issues better, and hopefully be used to develop methods that will prevent miscarriages.