Three-parent kids on the way

THE world’s first “three-parent baby” could be born in the UK by 2015. Parents at high risk of having children with severe disabilities such as muscular dystrophy will be offered a controversial new IVF (in vitro fertilisation) treatment after it was given the green light by ministers this week.

Up to 10 patients a year are expected to undergo the treatment, which involves replacing a fraction of the mother’s damaged DNA with that of a healthy donor.

The process avoids the risk of the mother passing on inherited defects that can lead to a host of debilitating conditions affecting the heart, muscles and brain.

The technique is controversial because it involves “germ line” modification of the embryo’s DNA, meaning the third party’s genetic material would not only be passed on to the child, but also to future generations down the female line.

Ministers will publish draft regulations later this year allowing the therapy to “high-risk” families. Public consultation conducted by the Human Fertilisation and Embryology Authority last year revealed overall support.

The technique is aimed at tackling hereditary conditions that are caused by mutated mitochondria — structures that supply power to human cells.

About 99.8% of human DNA, including all the genes that govern appearance and identity, is found in the nucleus of cells and is inherited evenly from both parents. But a small fraction resides in the mitochondria and is only passed on from mother to child.

Defects in the mitochondria can cause a range of serious problems, including muscular dystrophy, and affect about one in every 6 500 children born in the UK — greater than the number affected by childhood cancer.

Doctors will remove the nucleus from a donor egg and replace it with the equivalent genetic material from the mother’s egg, either before or after fertilisation by the father. The resulting egg can then be implanted and fertilised, if necessary, using standard IVF techniques.

Sally Davies, the chief medical officer for England, compared the process to changing a faulty battery in a car.

“Mitochondrial disease can have a devastating impact,” she said. “It’s only right that we introduce this life-saving treatment as soon as we can.”— © The Daily Telegraph, London