A team at a German university, led by Professor Karim Nayernia, have developed sperm from the stem cells of a mouse embryo, and created seven mice (six of which lived). It is the first time sperm has been created in laboratory conditions.
The development has been cautiously greeted. Some doctors believe the ability to do this may produce a greater understanding of male infertility - which contributes to about a third of all infertility problems experienced by couples - whilst others claim the nature of kinship presents moral issues in such a process.
Those mice which survived have suffered some health abonormalities such as breathing difficulties, and it is widely accepted that this move forward is many years away from being a therapy that could possibly be used for humans.
