Brit scientists brew up three-parent embryo

British scientists have successfully created "three parent" embryos using a technique they hope will offer "effective treatments for a range of serious hereditary diseases within five years".

The research could benefit mothers who suffer from mitochondrial DNA defects which might be inherited by their offspring and provoke any one of 40 different diseases, including those causing "fatal liver, heart and brain disorders, deafness, muscular problems and forms of epilepsy", as Reuters explains.

The Newcastle University team manipulated three DNA sources - the parents' nuclear DNA taken from a fertilised egg created by IVF, and an egg from a third party from which the nucleus had been removed. They transplanted the nuclear DNA into the nucleus-free host egg, thereby creating a foetus with its parents' genes inherited from the nuclear DNA but with the mitochondrial DNA of the second "mum".

Team member Patrick Chinnery summarised to Reuters: "The idea is simply to swap the bad diseased mitochondria - give a transplant, if you like - for good healthy ones from a donor. We're trying to prevent kids being born with fatal diseases."

The team experimented on "abnormal embryos left over from IVF therapy" to create the two-mum-one-dad embryos, which were "destroyed after six days".

Reuters concludes: "Stiff opposition to the technique is likely from critics of embryo research who fear the creation of designer babies." ®

Bootnote

Mitochondrial DNA is inherited exclusively from the mother. Sperm do carry mitochondrial DNA, but this is "destroyed" within the embryo after fertilisation.