By 2027 to 2037 scientists will likely be able to create a baby from human skin cells that have been coaxed to grow into eggs and sperm and used to create embryos to implant in a womb.
The process, in vitro gametogenesis, or I.V.G., so far has been used only in mice. But stem cell biologists say it is only a matter of time before it could be used in human reproduction — opening up mind-boggling possibilities.
With I.V.G., two men could have a baby that was biologically related to both of them, by using skin cells from one to make an egg that would be fertilized by sperm from the other. Women with fertility problems could have eggs made from their skin cells, rather than go through the lengthy and expensive process of stimulating their ovaries to retrieve their eggs.
IVF (Invitro fertilization) produces 70,000, or almost 2 percent, of the babies born in the United States each year. Worldwide there been more than 6.5 million babies born worldwide through I.V.F. and related technologies.
I.V.G. requires layers of complicated bioengineering. Scientists must first take adult skin cells — other cells would work as well or better, but skin cells are the easiest to get — and reprogram them to become embryonic stem cells capable of growing into different kinds of cells.
Then, the same kind of signaling factors that occur in nature are used to guide those stem cells to become eggs or sperm.
Last year, researchers in Japan, led by Katsuhiko Hayashi, used I.V.G. to make viable eggs from the skin cells of adult female mice, and produced embryos that were implanted into female mice, who then gave birth to healthy babies.
Mice embryos from skin cells and by 2037 human embryos from skin cells