Scientists have been working on making eggs and sperm from stem cells for a long time, and it seems like they have finally reached a tipping point.
Last Thursday in the leading journal Science, a group of Japanese researchers announced they’ve created immature human eggs from stem cells, which have themselves been derived from blood.
Although likely to cause some controversy, the paper could mark a potential advancement in human biology – especially biological mechanisms behind reproduction and the various consequences of having attained that knowledge.
“For the first time, scientists have been able to convincingly demonstrate that we are able to make eggs – very immature eggs”, said Amander Clark, a development biologist at UCLA who was not involved in the research.
The first step was fairly straightforward, as the research team deployed a well-established method for transforming adult human blood cells into induced pluripotent stem cells.
Next came the crucial step – according to Clark, the researchers then put the stem cells into a miniature artificial ovary (itself created from mouse embryonic cells), which produced a number of immature human eggs.
While the eggs created by the research team were far too immature to be fertilised, further elaboration of the technique could provide infertile couples with the opportunity to conceive and have children of their own.
However, in the near future this could lead to some unusual and ethically questionable consequences, such as babies ‘made’ from the cells of other children, grandparents, or even deceased people and celebrities.
“A woman might want to have George Clooney’s baby,” explained bioethicist Ronald Green from Dartmouth. “And his hairdresser could start selling his hair follicles online. So we suddenly could see many, many progeny of George Clooney, without his consent.”
With further advancements, this technique could also enable gay couples to have children with sperm and eggs made from their own skin cells, as well as have broader implications, such as scanning the DNA of foetuses and choosing which ones will get to see the light of day.
The next step for the researchers will be to try and create mature human eggs and sperm by refining their technique and thereby moving the field of reproductive biology even further ahead.