DNA breakthrough may prevent inheritable diseases

Devastating inherited diseases could be prevented using a pioneering fertility technique to swap DNA between eggs, scientists believe.

A breakthrough at the University of Newcastle opens up the possibility of avoiding mitochondrial disorders which can lead to early childhood death. The diseases are caused by defective DNA.

The new technique raises the hope of ensuring a baby does not inherit malfunctioning mitochondrial DNA from its Mother.

Around one in 6,500 children in the UK is severely affected by the disorders, which can cause muscle weakness, blindness, heart and liver failure, diabetes and learning disabilities.

There are currently no cures and mothers with a family history of the disorders normally face the agonising choice of risking having an affected child or no child at all.

Members of the Newcastle team used a DNA-transfer technique similar to that employed in cloning. It involves transferring nuclear DNA inherited from a child's parents to a donor egg carrying its own, properly functioning, mitochondria.

"What we've done is like changing the battery on a laptop," said Professor Doug Turnbull, one of the study leaders.

"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."

Professor Turnbull added: "This is a very exciting development with immense potential to help families at risk from mitochondrial diseases.

"We have no way of curing these diseases at the moment, but this technique could allow us to prevent the diseases occurring in the first place. It is important that we do all we can to help these families and give them the chance to have healthy children, something most of us take for granted."