Paging Aldous Huxley. The first piece of the Brave New World you ordered has arrived. Scientists from the University of Bath announced they have successfully produced a live and healthy mouse without using a fertilized egg. If this is possible in humans, it means we can reproduce using just a sperm and any ordinary body cells. What would Huxley think? What will the Mother’s Day card industry think?
Our work challenges the dogma, held since early embryologists first observed mammalian eggs around 1827, and observed fertilisation 50 years later, that only an egg cell fertilised with a sperm cell can result in live mammalian birth.
Molecular embryologist Dr Tony Perry, senior author of the study published in Nature Communications, knows he and his colleagues are turning the chicken-and-egg conundrum upside-down with this discovery of egg-less fertilization.
The process is not as simple as mixing sperm and cells in a Petri dish and requires a bit of sleight-of-hand (no, this isn’t a reference to how the sperm was obtained). Instead of an egg, the researchers used an inactive mouse embryo known as a parthenogenote. (Parthenogenesis is asexual reproduction found in some insects, fish, reptiles and other creature but not in mammals)
The parthenogenote started out as a mouse egg that was tricked into becoming an embryo using a salt called strontium chloride (SrCl2). The parthenogenote was then injected with mouse sperm, causing fertilization and resulting in a live baby mouse. Over the course of the study, 30 baby mice were born with a success rate of 24 percent – a much higher rate than achieved by cloning. Some of the motherless mice later had healthy babies conceived in the conventional way.
Wait a minute. How can this be called “egg-less” when the whole process started with an egg? Good question! They used an egg because it’s the easiest cell to turn into a parthenogenote. However, they claim that theoretically any human cell can become a parthenogenote once half of its chromosomes are removed, allowing them to then fuse with the sperm’s chromosomes. Perry says that’s the next step for his team.
Since we know that anything tried successfully on mice eventually ends up being used on people, what does this mean for human reproduction?
This process expands the possibilities for women who can’t produce eggs normally to use other cells to have a child. It opens the door for two men to have a baby which has DNA from both of them. It could even allow one man to have a baby using just his own cells and sperm. Dr. Perry calls these scenarios “speculative and fanciful” at the moment. (That will probably change when Chinese scientists figure out how to do it – they’re already making sperm cells from stem cells).
Also, until we have a Brave New World of “hatcheries and conditioning centres,” the process still needs females to carry the motherless embryos to term.
What happens when you open a can of motherless worms?