British scientists have been granted permission to genetically modify human embryos by the fertility regulator. The
Francis Crick Institute could begin thecontroversial experiments as
early as March after the Human Fertilisation and Embryology
Authority(HFEA) gave the green light this morning.
The scientists want to deactivate genes in leftover embryos from IVF clinics to see if it hinders development.
It will only be the second time in the world that such a procedure has
been undertaken and the first time it has been directly approved by a
regulator. A Chinese team carried out similar experiments last year to
widespread outcry.
Currently around 50 per cent of fertilised eggs do not develop properly
and experts believe that faulty genetic code could be responsible.
If scientists knew which genes were crucial for healthy cell division,
then they could screen out embryos where their DNA was not working
properly, potentially preventing miscarriages and aiding fertility.
The initial pilot, which will also have to pass an ethics evaluation,
will involve up to 30 embryos and the team would like to work on a
further three genes, which could bring the total of to 120.
Critics warn that allowing embryos to be edited opens the door to designer babies and genetically modified humans.
But lead scientist Dr Kathy Niakan said that the research could
fundamentally change our understanding of human biology and give hope to
prospective parents.
“We would really like to understand the genes that are needed for an embryo to develop into a healthy baby,” she told a briefing in central London last month.
“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 at Francis Crick are already in talks with fertility clinics across the country to use their spare embryos.
Sir 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.”
Currently it is not illegal to edit human embryos for research purposes
although it has never been done before because they technology has not
been available.
When China announced it had carried out similar experiments last year there was a widespread outcry.
A spokesman for the HFEA said:
“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 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.
“As with all embryos used in research, it is illegal to transfer them to a woman for treatment.”
All cells in a human embryo have the same DNA code, but they divide into specialised cells depending on gene expression.
Between day five and seven of human development and embryo has around
200 cells of three different types. One set will go on to form the
foetus , while another type becomes the placenta, and the third kind the
yolk sac which nourishes growing baby. The aim of the new project is to
find out what causes the cells to turn into different kinds, a process
known as ‘lineage specification.’
The new genetic editing technique, called Crispr, acts like molecular
scissors to snip out part of the DNA code so that scientists can see if
it was needed.
“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.
The first gene that the team is planning to deactivate is OCT4, which in
mice appears to be crucial for the healthy development of foetal cells.
However British scientists were among 150 experts who in November called
for a worldwide ban on genetic editing of embryos claiming the practice
could open the door to ‘irrevocably altering the human species.’
Dr Calum MacKellar, Director of Research of the Scottish Council on
Human Bioethics said: “Allowing the gene editing of embryos opens the
road to genetically modifying all the descendants of a person as well as
full blown eugenics which was condemned by all civilised societies
after the Second World War.”
“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.”
Gene therapy has been available since the 1970s but it is only recently
that scientists have developed technology which can snip out parts of
genetic code
The technique could permanently remove harmful mutations which lead to
inherited diseases like Huntingdon’s, cystic fibrosis and haemophilia,
critics say it could have unexpected side effects any may damage healthy
strands of DNA.
Alastair Kent, Director of Genetic Alliance UK, said: "“Understanding
the crucial process of embryo development could help us to understand
causes of infertility, miscarriage and some genetic diseases.
"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."
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