The embryos, each containing genetic material from one man and two women, have been produced in a project that could lead to the first genetically altered babies being born in Britain. Scientists at Newcastle University have grown human embryos after merging DNA from two fertilised eggs, with a technique that could soon be used to prevent serious genetic disorders that affect 100 children in Britain each year, according to Daily Telegraph (UK).
The aim is to correct faulty mitochondria (or “cellular batteries”) which can cause around 150 known diseases – such as fatal heart, liver, neurological and muscle conditions, by replacing them with healthy ones from a donated embryo. A child would inherit genetic material from three parents. The mother and father would supply 99.8 per cent of its DNA, with a small amount from another woman, the mitochondrial donor.
Prof Doug Turnbull, who led the research, said: “A child born using this method would have correctly functioning mitochondria, but in every other respect would get all their genetic information from their father and mother.”
“What we’ve done is like changing the battery on a laptop. The energy supply now works properly, but none of the information on the hard drive has been changed. A child would have correctly functioning mitochondria but in every other respect would get all their genetic information from their father and mother. This technique could allow us to prevent the diseases occurring,” he added.
However, under the Human Fertilisation and Embryology Act 2009, it is currently illegal to create babies using embryos which have been manipulated in the laboratory, but the Health Secretary can rescind the ban without legislating.
Alison Murdoch, another leader of the team, said: “I don’t think we have the information yet to go to the Secretary of State. But we think the time is right to enter discussions about what information will be required for the Secretary of State to make that provision.”
One in 200 children is born each year with genetic mutations in the mitochondria — energy-producing structures in cells inherited from the egg. The effects are usually mild, but in 1 in 6,500 people incurable disease is caused.
In this technique, embryos are created by IVF, using the mother’s eggs and her partner’s sperm. After fertilisation two “pronuclei” from the egg and sperm, containing the parents’ DNA, are removed. These are injected into a donated embryo with healthy mitochondria, from which the pronuclei have been removed.
In the experiments, reported in Nature, the scientists showed that this method was practical, using faulty embryos left over after IVF and donated for research. About 8 per cent of the modified embryos grew normally to the blastocyst stage of 100 to 150 cells, indicating that they could be viable.
The scientists expect better results with normal embryos, rather than abnormal ones discarded after IVF. They are seeking to conduct such research. [image via BabiesToday; via TimesOnline (UK) and Daily Telegraph (UK)]