Scientists create human eggs from skin cells in a breakthrough

For centuries, the story of human reproduction was simple. A sperm met an egg, and life began. Now, researchers in the US have rewritten that story by creating human eggs from skin cells, a feat that could transform fertility treatment.

Scientists at Oregon Health and Science University have reported a milestone in reproductive medicine. For the first time, they have taken the DNA from human skin cells and used it to produce eggs that could be fertilised with sperm. The research, published in Nature Communications, has been described as a proof of concept that could one day help millions struggling with infertility.

The method works by removing the nucleus, which contains all the genetic code, from a skin cell. This nucleus is then placed inside a donor egg that has been emptied of its own DNA. To succeed, the egg must shed half of its chromosomes before it is ready for fertilisation. The team coined the term "mitomeiosis" for this artificial division process.

Out of 82 eggs created, only a small fraction developed into early embryos. None grew beyond six days, and many showed chromosomal abnormalities. Despite these hurdles, researchers remain optimistic. "We achieved something that was thought to be impossible," said Professor Shoukhrat Mitalipov, who led the study. "Eventually, I think that is where the future will go, because there are more and more patients that cannot have children."

Experts have praised the work but warned of challenges ahead. Professor Richard Anderson of the University of Edinburgh called it "a step towards helping many women have their own genetic children," but stressed that safety must come first.

The science is still far from clinical use, however, it opens new possibilities. As Professor Roger Sturmey of the University of Hull noted, such advances demand "robust governance, to ensure accountability and build public trust."