Updated

Britain has granted permission to scientists to create a human embryo with genetic material from two mothers, officials said.

Scientists from Britain's Newcastle University plan to transfer the pro-nuclei (search) — the components of a nucleus of a human embryo — by a man and woman into an unfertilized egg from another woman to prevent mothers passing certain genetic diseases (search) to their unborn babies.

The application was initially rejected because of legislation prohibiting the alteration of the genetic structure of a cell while it is forming part of an embryo, the Human Fertilization and Embryology Authority said in a statement Thursday. The authority is a government body that regulates fertility treatment and research.

The scientists eventually were given permission after reviewing the legislation.

The research could eventually lead to techniques that might prevent the transmission of genetic defects, researchers say.

"While the proposed technique has been found to be safe in animal embryos, it will be very important to determine whether it can safely be used in human eggs," university spokesman Mick Warwicker said.

No treatment exists for mitochondrial diseases (search), which arise from DNA outside the nucleus and are inherited separately from DNA in the nucleus.

The research does not involve human cloning (search). It would use normal IVF (search) procedures, but before the sperm and egg fused, components would be implanted into a healthy female egg.