'Human-animal' embryo ruling due

Regulators are due to make a decision whether to allow human-animal embryos to be created and used for research.The Human Fertilisation and Embryology Authority is expected to give the plan the go-ahead in principle - but each case will still be judged individually.

Scientists want to create hybrid embryos by merging human cells with animal eggs in a bid to extract stem cells.

The cells form the basic building blocks of the body and have the potential to become any tissue, making them essential for research.

At the moment, scientists have to rely on human eggs left over from fertility treatment, but they are in short supply and are not always good quality.