UK to become first country to offer “three parent” fertility treatment

The UK plans to become the first country in the world to offer controversial ''three-parent'' fertility treatments to families who want to avoid passing on  incurable diseases to their children.

The methods, in the research stage in laboratories in the UK and the US currently, would involve implantation of genetically modified embryos into women,  which has raised serious ethical questions.

The techniques involve intervention in the process of fertilisation to remove faulty mitochondrial DNA, which could cause inherited conditions including fatal heart problems, liver failure, brain disorders, blindness and muscular dystrophy.

A new IVF technique developed by British fertility experts allows them to take thousands of snapshots of a developing embryo, that they say could help doctors pick those most likely to implant successfully and develop into healthy babies.

According to these experts, the technique is designed to help families with mitochondrial diseases - incurable conditions passed down the maternal line that affect around one in 6,500 children worldwide. Mitochondria function like tiny energy-generating batteries inside cells.

The controversial potential treatment is called three-parent in vitro fertilisation (IVF) as the offspring would get its genes from a mother, a father and from a female donor.

Following a national public consultation, which showed that the technique was generally supported by UK citizens, the government's chief physician cleared it under strict regulation.

''Scientists have developed ground-breaking new procedures which could stop these diseases being passed on, bringing hope to many families seeking to prevent their children inheriting them,'' Sally Davies, chief medical officer, told reporters.

However, some groups are opposed to the procedure due to the destruction of IVF embryos in one approach. As the technique also makes modifications to an embryo what would be passed on to future generations there is also a risk of unforeseen complications affecting generations to come.

The procedure has worked in animals, but remains untested in humans and for this reason according to  Davies, any babies born through the process would need to be followed up to ensure they were healthy.

Davies added it was not a decision to be taken lightly.

If approved, five to 10 of the most severe cases could be treated in the UK each year, with the number projected to increase due to faulty mitochondria being linked to an ever greater range of medical problems, including diabetes, deafness, Parkinson's disease and even obesity.

Speaking at a briefing in London on Thursday, Davies said mitochondrial disease could have a "devastating impact" on families.

Mitochondria contain only 37 genes, which are crucial to the energy supply of cells, while the majority of our DNA, the 23,000 genes that determine our appearance and much else, are locked in the cell nucleus.