It may soon be possible to coax human skin cells into becoming functional eggs and sperm using a technique known as “in vitro gametogenesis”. This involves the creation (genesis) of eggs and sperm (gametes) outside the human body (in vitro).
Animal studies have been promising. In 2012, scientists created live-born baby mice using eggs that began their life as skin cells on a mouse tail.
More recently, the technique has been used to facilitate same-sex reproduction. Earlier this year, scientists created mouse pups with two genetic fathers after transforming skin cells from male mice into eggs. Mouse pups with two genetic mothers have also been created.
Scientists have not yet managed to adapt these techniques to create human gametes. Perhaps because the technology is still in its infancy, Australia’s legal and regulatory systems do not address whether and how the technology should be used.
First, in vitro gametogenesis could streamline IVF. Egg retrieval currently involves repeated hormone injections, a minor surgical procedure, and the risk of overstimulating the ovaries. In vitro gametogenesis could eliminate these problems.
Second, the technology could circumvent some forms of medical infertility. For example, it could be used to generate eggs for women born without functioning ovaries or following early menopause.
Third, the technology could allow same-sex couples to have children who are genetically related to both parents.
If we took skin cells from each male partner and created an embryo, that embryo would still need a surrogate to carry the pregnancy. Unfortunately, Australia has a shortfall of surrogates. International surrogacy provides an alternative, but carries legal, ethical and practical difficulties. Unless access to surrogacy is improved domestically, benefits to male couples will be limited.
In vitro gametogenesis also raises questions about who are the future child’s legal parents. We already see related legal debates surrounding non-traditional families formed through surrogacy, egg donation and sperm donation.
In vitro gametogenesis could theoretically also be used to create children with more than two genetic parents, or with only one. These possibilities likewise require us to update our current understandings of parenthood.
Finally, in vitro gametogenesis could revolutionise prenatal genetic selection. We’d have many more embryos than available during regular IVF to screen for genetic diseases and traits.
So it would be urgent to discuss “designer babies”, eugenics, and whether we have a moral obligation to conceive children with the best chance of a good life.