In a landmark ruling, researchers have received approval from British regulators to conduct gene editing ("genetic modification") on human embryos.
A group led by biologist Kathy Niakan at London's new Francis Crick Institute plans to use the CRISPR/Cas9 genome editing technique on human embryos for research purposes only. The aim of the research is to understand more about the genes human embryos need to develop properly, with the hope that this knowledge could help improve infertility treatments and prevent miscarriages.
Niakan's group applied to the Human Fertilisation and Embryology Authority (HFEA) for approval of the research last year.
"Our Licence Committee has approved an application from Dr Kathy Niakan of the Francis Crick Institute to renew her laboratory's research licence to include gene editing of embryos," the HFEA said in an emailed statement.
"The committee has added a condition to the licence that no research using gene editing may take place until the research has received research ethics approval," the HFEA added. "As with all embryos used in research, it is illegal to transfer them to a woman for treatment."
"Investigating gene function in early human embryogenesis would allow us to gain significant insights into the fate of cells during early human development."
In the HFEA's inspection report, the scientists explain their goal: "The aim of our research is to understand which factors human embryos require to develop successfully and in addition to establish new human stem cells for therapeutic applications. Our investigations will be important to assess whether IVF [in vitro fertilisation] technologies could be improved to increase healthy pregnancy outcomes."
The embryos used in the research will be surplus embryos donated by patients undergoing IVF treatment. In a statement, the Francis Crick Institute explained that the researchers will be looking at gene development in the very early stages—the first seven days of the fertilised egg's development, when it grows from one to around 250 cells—and emphasised that the embryos cannot be used in treatment.
"I am delighted that the HFEA has approved Dr Niakan's application," said Crick Director Paul Nurse in the statement. "Dr Niakan's proposed research is important for understanding how a healthy human embryo develops and will enhance our understanding of IVF success rates, by looking at the very earliest stage of human development—one to seven days."
Gene editing using CRISPR/Cas9 involves targeting specific genes in the DNA and "cutting" the DNA in that position using the Cas9 enzyme. This can be used to deactivate a certain gene in order to see what role it plays. Niakan's team will be looking at genes thought to be involved with embryo development, and plan to start with a gene called Oct-4 to explore what role it plays in human embryo development. They'll then move on to other genes too.
"It will be important to functionally test if these genes, or others like them, are functionally required for human pluripotency [where stem cells develop into other cells] in the embryo," they write in the proposal. "Investigating gene function in early human embryogenesis would allow us to gain significant insights into the fate of cells during early human development. This in turn would enable us to develop more objective criteria for embryo selection and increase the efficiency of stem cell derivation."
The approval is bound to reignite global debate over human genome editing, with some fearing a "slippery slope" toward designer babies. The UK has been a leading supporter of allowing gene editing in human cells and embryos for research purposes, with a group of high-level research and medical authorities last year signing a statement of support for continued work in the field. Meanwhile, the US National Institutes of Health last year reiterated a ban on gene editing in human embryos, stating it "will not fund any use of gene-editing technologies in human embryos."
Subject to ethical approval, the Crick Institute writes that the research will begin within months.