Scientists have created human sperm for the first time from stem cells. The research, carried out at Newcastle University in Britain, may enable infertile men to have children, while provoking another ethical debate about the progress of reproductive biology.
Karim Nayernia, the project leader, said the “in vitro designed” sperm produced in his lab looked fully mobile and functional under the microscope, though more research would be needed before IVD sperm were used to fertilise human eggs. The work might lead to a fertility treatment in five to 10 years, he said.
The Newcastle scientists cultured stem cells, derived from a male embryo, with special chemicals to set them on the path towards becoming sperm. A few of the cells underwent the crucial step of meiosis – cell division – followed by growth into mobile sperm with a head (to fertilise the egg) and tail (for mobility).