Early stage sperm created from skin

Scientists have created early stage sperm from the skin of men who cannot make their own, raising hopes of new treatments for currently incurable male infertility.

A leading British expert said the stem cell research challenged the widely held view that the ‘door is closed’ on men with the problem who want to have children.

Although still at a very early stage, the study raises the future prospect of lab-grown sperm that could allow them to become fathers.

More immediately, it offers researchers a new tool for studying sperm development and assisted conception treatments.

Lead scientist Reijo Pera, from the Institute for Stem Cell Biology and Regenerative Medicine at Stanford University, US, said: “Our results are the first to offer an experimental model to study sperm development. Therefore, there is potential for applications to cell-based therapies in the clinic, for example, for the generation of higher quality and numbers of sperm in a dish.

The study raises the future prospect of lab-grown sperm that could allow them to become fathers

“It might even be possible to transplant stem-cell-derived germ cells directly into the testes of men with problems producing sperm.”

Infertility affects 10 to 15 per cent of couples and in men often has a genetic origin, most commonly the loss of key genes on the male Y chromosome.

All three infertile men taking part in the new study had missing regions of Y chromosome DNA associated with the production of few or no sperm.

Reijo said: “Our studies suggest that the use of stem cells can serve as a starting material for diagnosing germ cell defects and potentially generating germ cells.

“This approach has great potential for treatment of individuals who have genetic/idiopathic (un­known) causes for sperm loss or for cancer survivors who have lost sperm production due to gonadotoxic treatments.”