Scientists say they have bred mice using eggs originating from male cells, in a breakthrough which could one day pave the way for human male couples to have children.
Researchers claim they successfully created the eggs by turning male XY chromosome pairs from the skin cells of male mice into female XX chromosome pairs.
This was achieved by converting the skin cells into stem cells, deleting the Y chromosomes, copying the x chromosomes and then pairing the copies with the original X chromosomes.
This allows the stem cell to be programmed to become an egg. The egg was then fertilised with sperm from another mouse.
Researchers say the technique was used to create seven mice pups, which appeared healthy and had a normal lifespan.