This undated photo provided by researcher Katsuhiko Hayashi shows an adult mouse which was born from an egg cell produced from a skin cell, and her pups born normally. The eggs were produced by making skin cells revert to a kind of blank slate, so they could be prodded to develop into immature egg cells.
EXPERIMENTS which turned mice stem cells into viable eggs used to create offspring via in vitro fertilisation would be fraught with scientific and ethical hurdles in humans, Australian researchers say.
The findings, by Japanese researchers and published in the journal Science Express, showed eggs created from the mice stem cells could be fertilised and transplanted into female mice who gave birth to newborn pups.
But Australian researchers warned that although the findings showed it might be possible to create eggs from human stem cells in the same way, this was not an option at present.
“The study suggests that it may be possible one day to create functioning usable human eggs, called oocytes, but this is not feasible or viable at this time,” said Bryce Vissel from the Garvan Institute of Medical Research in Sydney.
Dr Vissel said creating human eggs would remain fraught with scientific challenges and hurdles, including major questions relating to viability, reliability and safety.
He said the real importance of the study was that it could allow more investigation into how human female eggs developed.
Reproductive professor at the University of Adelaide, Robert Norman, said the research offered hope to infertile couples who wanted their own children, but application in humans was still a long way off.
“For many infertile couples, finding they have no sperm or eggs is a devastating blow for which there is no solution other than to not have children, or to use donor gametes,” he said.
Using donors was a complex emotional and social issue, Prof Norman said.
“If a person with no gametes could use their own cells to create a child, all the problems would disappear.”
It also had the potential for post-menopausal women to have children, raising even more ethical issues, he said.
Associate Professor Kuldip Sidhu, director of the Stem Cell Lab at the University of NSW, said the biggest question mark over the study was whether the same process would work with human embryonic stem cells.