Scientists make mice from non-egg cells

Scientists have shown for the first time that offspring can be made from non-egg cells, a discovery that challenges two centuries of received wisdom. 

Eggs can be 'tricked' into developing into an embryo without fertilisation, but the resulting embryos, called parthenogenotes, die after a few days because key developmental processes requiring input from sperm don’t happen.

However, scientists from the Department of Biology & Biochemistry at the University of Bath have developed a method of injecting mouse parthenogenotes with sperm that allows them to become healthy baby mice with a success rate of up to 24 per cent. This compares to a rate of zero per cent for parthenogenotes or about two per cent for nuclear transfer cloning.

Molecular embryologist Dr Tony Perry, senior author of the study, said: “This is first time that full term development has been achieved by injecting sperm into embryos. “It had been thought that only an egg cell was capable of reprogramming sperm to allow embryonic development to take place.

“Our work challenges the dogma, held since early embryologists first observed mammalian eggs around 1827 and observed fertilisation 50 years later, that only an egg cell fertilised with a sperm cell can result in a live mammalian birth.”

Mice born by this method appear healthy and are able to produce at least two generations of offspring.