Mouse spermatogonial stem cells can be differentiated into sperm in the laboratory and produce healthy offspring after micro-insemination. Published in Nature Communications this week these findings suggest that this mouse system can be used to investigate the development of sperm in the laboratory.

Previous work has demonstrated that spermatogonial stem cells can be propagated in the laboratory but these only differentiate to sperm within organisms. Now, Takehiro Ogawa and colleagues have extended this work to identify culture conditions that allow the generation of the sperm in the laboratory. These mouse sperm were used to fertilise eggs in the laboratory and viable offspring could be produced from the fertilized eggs.

These findings will permit the detailed investigation of spermatogenesis in the laboratory.