UK scientists gain approval to edit genes in human embryos

Graphic by Jennifer Doudna/UC Berkeley

UK scientists have gained approval to use the new “gene editing” technique on human embryos for research, announced HFEA, UK’s fertility regulator.

The approval came through, after a group at the Francis Crick Institute led by group leader, Dr Kathy Niakan applied for a research license to use CRISPR-Cas9 to understand the genes, human embryos need to develop successfully. It is purely meant for research purposes and will look at the first seven days of a fertilised egg’s development (from a single cell to around 250 cells).

Paul Nurse, director of the Crick, said: “I am delighted that the HFEA has approved Dr Niakan’s application. 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.”

The approval by Human Fertilisation and Embryology Authority (HFEA) marks the first time any national regulatory authority has endorsed the use of CRISPR-Cas9 for germline editing. However, it has added a condition to the license that no research using gene editing may take place until the research has received research ethics approval.

Needless to say, “As with all embryos used in research, it is illegal to transfer them to a woman for treatment.” What this means is the gene editing technique could help researchers to develop treatments for infertility, but will not themselves form the basis of a therapy.

In line with HFEA regulations, any donated embryos will be used for research purposes only and cannot be used in treatment. These embryos will be donated by patients who have given their informed consent to the donation of embryos which are surplus to their IVF treatment. The genome editing research now needs to gain ethical approval and, subject to that approval, the research programme will begin within the next few months.

Dr Kathy Niakan’s research

Kathy Niakan 10-1-14_900px
Dr. Kathy Niakan Credit: Francis Crick Institute

In a briefing in central London last month, Dr Kathy Niakan said “We would really like to understand the genes that are needed for an embryo to develop into a healthy baby. Miscarriage and infertility are extremely common but they are not very well understood. We believe that this research could improve our understanding of the very earliest stages of human life. “

“The reason why I think this is so important is that most human embryos fail to reach the blastocyst stage. Over 50 per cent will fail so this window is absolutely critical. If we were to understand the genes, it could really help us improve infertility treatment and provide crucial insights into the causes of miscarriage.”

The team is planning to deactivate or block the ‘master regulator ‘ gene called OCT4, that appears to be crucial for the healthy development of foetal cells. When the human embryo is between 5-7 days old, they typically consist of around 200 cells of three different types. One set develops into the foetus, while the other becomes the placenta and the third one becomes the yolk sac that nourishes the growing baby. The group wants to learn about what causes these cells to turn into different kinds, a process known as “lineage specification”.

CRISPR-Cas9, the new gene editing technique acts like molecular scissors that can edit parts of the DNA code so that scientists can see if those missing pieces were needed in the first place.

Giving an analogy, Dr Niakan said “If you imagine the genome as volumes in an encyclopaedia, at some point in the development some of the cells will start to read a different volume compared to its neighbour cell. One cell will read a volume slightly differently even though they have the same library.”

“CRISPR is so efficient and precise that it can go inside a single volume, open up, a specific page, identify a single word, and alter a single letter,” added Prof Niakan.

Scientific community reacts..

Robin Lovell-Badge, a developmental biologist at the Crick institute feel that the decision could have a ripple effect and will give scientists the confidence to apply to their national regulatory bodies to do similar experiments.

Sarah Chan, a bioethicist at the University of Edinburgh, UK says “I think this will be a good example to countries who are considering their approach to regulating this technology. We can have a well-regulated system that is able to make that distinction between research and reproduction.”

Alastair Kent, Director of Genetic Alliance UK, said “The team at the Crick Institute have explained to the HFEA why they would like to use genome editing to investigate embryo development and the HFEA have authorised the research to proceed. We hope that this avenue of research is fruitful, and that genome editing is as powerful a research tool as it currently seems to be.”

But its not all rosy, as there are numerous critics too who fear that allowing embryos to be edited opens the door to designer babies and genetically modified humans. In early 2015, a Chinese team carried out similar experiments to widespread outcry and international debate over regulations.

Since the technique could specifically and permanently remove harmful mutations which lead to inherited diseases like Huntingdon’s, cystic fibrosis and haemophilia, critics say it could have unexpected side effects and may damage healthy strands of DNA.

Dr Calum MacKellar, Director of Research of the Scottish Council on Human Bioethics said: “It is the very future of the way in which societies accept persons with disabilities that is at play since such gene editing procedures infer that they should not have been brought into existence.”