Mature mouse eggs produced in the lab

A team of Japanese scientists has successfully matured mouse eggs in the laboratory, opening up the possibility of preserving the fertility of young female cancer sufferers.

The research team, led by Izuho Hatada, took very early eggs from mouse fetuses and were able to mature them and use them to produce viable offspring who were themselves fertile. They team wasn't, however, able to mature the eggs in vitro without using the cytoplasm (outer shell) of fully matured eggs. Using nuclear transfer techniques, the team transferred the genetic material from the immature eggs into mature eggs. The eggs were then fertilised using IVF and transferred into surrogate mice, who produced viable pups.

The use of nuclear transfer to produce mature eggs will make it difficult to use the egg maturation procedure in humans, but the team, from Gunma University in Japan, have made a significant step towards enabling young girls or women facing cancer treatment to preserve their immature eggs for future use.