New Hope for Parents; North East Scientists in DNA Advance

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Byline: Helen Rae

AMAJOR breakthrough by scientists in the North East is offering hope that a host of incurable inherited diseases could be banished.

A team at Newcastle University has developed a pioneering technique which allows the successful transfer of DNA between two human eggs.

The advance brings hope to parents who know any children they have would be born with diseases such as muscular dystrophy and other conditions with symptoms like deafness, dementia and progressive neuro-degenerative disorder.

It is the first time such a technique has been used in fertilised human eggs and it is believed it could be commonly available in three years' time.

However, significant legal and ethical challenges could lie ahead.

Last night, one pro-life campaigner said it would be a step too far in meddling with human genetics and told of her fear that it would be a move towards "designer babies".

The landmark project, led by Newcastle neurologist Prof Doug Turnbull and embryologist Dr Mary Herbert, has the potential to help prevent the transmission of inherited disorders known as mitochondrial diseases.

The technique involves implanting the nucleus of an embryo of a mother with defective DNA into the egg of a woman with healthy DNA.

People with defects of mitochondrial DNA have a number of clinical problems, including severe muscle disease, epilepsy, dementia, and increased risk of strokes and heart failure.

Prof Turnbull said: "It is a very exciting development and an important step towards trying to prevent diseases from mother to child.

"It is the first time this has been done with human embryos and 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.

We have no way of curing these diseases at the moment, but this tech-nique could allow us to prevent the diseases occurring in the first place."

Around one in 200 children are born each year with mutations which, in most cases, cause only mild or asymptomatic forms of mitochondrial disease.

However, around one in 6,500 children are born with severe mitochondrial diseases, which include muscular weakness, blindness, fatal heart failure, liver failure, learning disability and diabetes, and can lead to death in early infancy.

In the absence of cures for these conditions, women face having a child who may be affected by such a disease or not having children at all.

The Newcastle team created 80 fertilised eggs which were cultured for six to eight days in the laboratory to monitor development.

In some cases, a very small amount of the mother's mitochondrial DNA was carried over to the new egg. However, since severe diseases only occur with large amounts of mutations, this would be very unlikely to affect a child's health.

The team is now planning further studies that will provide more evidence of the safety of this procedure. Prof Turnbull said: "I am hopeful we will get the approval we need to continue what we have started."

The Newcastle researchers used abnormally fertilised eggs from consenting couples undergoing IVF treatment. …