Soon, there could be much safer and easier ways to reproduce, and sex as we know it could be over.
Eggs and sperm can be obtained from human skin PHOTO Getty
Until about a century ago, humans created embryos and children in the same old, largely random way—through sex. Then some started using artificial insemination and, 45 years ago, in vitro fertilization. These technologies still involve human eggs and sperm, but thanks to stem cell technologies, this will change, writes BBC Science.
The radical change will be represented by in vitro gametogenesis (IVG) – the transformation of skin cells into induced pluripotent stem cells, then their transformation into eggs and sperm. IVG is extremely exciting for millions of couples, but it also raises some delicate questions.
For example, if we could produce eggs from skin cells, 90-year-olds could become genetic parents. So are nine-year-olds, fetuses lost during pregnancy, or people who have died many years ago and whose cells have been frozen.
What if we could produce sperm from women's skin cells or eggs from men's? This could soon become a reality. In 2023, Japanese scientists announced that they had produced eggs from the skin cells of a male mouse and, using “normal” mouse sperm, produced baby mice.
To take this idea further, what would happen if we produced both eggs and sperm from the same person and used them to make embryos? The “unibaby” would not be a clone, but more like you than your siblings. An even more radical idea called “multiple parenting” could involve creating embryos from four people, which would then be used to produce eggs and sperm.
Technology in development
Another technology that could end reproduction as we know it is the power to modify an embryo's DNA. Targeted editing of specific sequences in a cell's DNA has become possible thanks to a revolutionary tool invented in 2012 that targets CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) DNA sequences.
When you edit the DNA in an early embryo, you edit the DNA in what will become all of its cells—including its eggs and sperm. Such a modification can be transmitted to the offspring of this embryo indefinitely.
The most plausible use of this DNA editing technology is to prevent disease or disabling conditions in children. Most frightening, though implausible, is the use of technology to create “superkids” who would not only have greater abilities, but also pass them on to their offspring. Some believe that we should never be allowed to change the DNA of our offspring, potentially forever; others believe we should not use it now because it is not proven to be safe or effective.
Another technology that could make reproductive sex even more redundant is the development of artificial wombs. Over 90 years ago in “A happy world“, Aldous Huxley predicted a situation where human fetuses would develop in bottles.
In 2017, researchers reported the survival of lambs born a week or two early in liquid-filled plastic bags. More recently, the US Food and Drug Administration held a public meeting to consider whether, when and how to conduct studies with such artificial wombs on babies.
The artificial womb, about to become a reality
These devices are, in fact, early incubators. They might delay viability for premature babies by a week or two, from (at most) around 22 weeks of pregnancy to around 20, but that baby would still have to have spent four and a half months developing inside a women.
This method might be great for premature babies and their parents, but it wouldn't make much of a difference for most of us.
But a “genuine” artificial womb—one into which a six- or seven-day-old embryo could be placed and aided in its nine-month development into a healthy newborn—would remove not only sex from child-making, but also pregnancy. Some may welcome the technology with open arms. Others, no doubt, would be concerned.
All this could not be impossible in the distant future. Much of the long-term research focuses on using stem cells to grow human organs. The focus is on vital organs for transplants – kidneys, livers, hearts – but if they can be grown, why not a uterus?
Imagine that organ, grown from a woman's stem cells, connected to a machine that would provide blood, sugar, oxygen and all the necessary hormones, as well as waste treatment – then add an embryo. Such a “womb” could, in theory at least, replace a woman's uterus. But should it? Our children and grandchildren will probably have to make that decision.
