Scientists have created mice with two biological parents after obtaining eggs from male cells, an achievement that could pave the way for new treatments for human fertility, writes The Guardian.

The study’s findings could eventually pave the way for treatments for severe forms of infertility, as well as increase the likelihood that people of the same sex will be able to have a biological child together in the future, the study authors said.

“This is the first case of producing robust mammalian oocytes from male cells,” said Katsuhiko Hayashi, who led the research at Kyushu University in Japan and is a world-renowned pioneer in the field of laboratory-grown eggs and sperm.

A viable human egg from a skin cell after decades?

Hayashi, who presented the research at the Third International Summit on Human Genome Editing at the Francis Crick Institute in London on Wednesday, predicts that it will be technically possible to create a viable human egg from male skin within a decade. Others suggest that this timeline is optimistic, given that scientists have yet to create viable human eggs grown in the lab from female cells.

This is the first time that viable eggs have been grown from male cells and marks a significant advance. Hayashi’s team is now trying to replicate this achievement using human cells, although using lab-grown eggs for clinical purposes, including establishing their safety, will have significant hurdles.

“From the point of view of technology, it will be possible [la oameni] even in 10 years,” he said, adding that he would personally support the technology, which is being used clinically to allow two men to have a child if the procedure is proven safe.

The technique could also be used to treat severe forms of infertility, including in women with Turner syndrome, in which one of the X chromosomes is partially or completely missing, and Hayashi said this idea was the main motivation for the research.

But what are the obstacles and dangers there

Others suggest that applying the technique to human cells may prove difficult. Human cells require much longer culture periods to produce a mature egg, which can increase the risk of the cells acquiring unwanted genetic changes.

Professor George Daly, dean of Harvard Medical School, said Hayashi’s achievement was “exciting”, but added that other research had shown that it was more difficult to create lab-grown germ cells from human cells than from mouse cells. “We still don’t understand enough about the unique biology of human gametogenesis to replicate Hayashi’s complex work in mice,” he said.

The research, which was submitted for publication in a major medical journal, relied on a sequence of complex steps to transform a skin cell containing the male XY chromosome combination into an egg with the female XX version.

Professor Amander Clarke, who works on lab-grown gametes at the University of California, Los Angeles, said transferring the work to human cells would be a “huge step” because scientists have yet to create lab-grown human eggs from female cells.

Scientists have created precursors to human eggs, but until now the cells stopped developing before meiosis, a critical stage of cell division required for the development of mature eggs and sperm.