Japanese Researcher announced that he had created viable eggs from the cells of male mice. This is the first laboratory creation of mammalian oocytes from male cells. The next – tricky – step will be to find something similar to human cells, since there is, among other things, the risk of causing unwanted genetic changes.

The research, which is still in its early stages, concerns the transformation of male XY chromosomes into female XX. This development paves the way for male couples to have children of their own rather than through adoption.

Cautions

The announcement was made by Professor Katsuhiko Hayashi of Osaka University, who enjoys an international reputation in his field, at a conference of the Francis Crick Institute of Genetics in London, according to the BBC and Guardian. The other scientists looked wary. Professor George Daly of Harvard Medical School, USA, has pointed out that it will be a long time before society is faced in practice with the choice of children from two fathers.

Hayashi himself has stated that his work is at a very early stage. The eggs he created are of poor quality and the method cannot currently be used safely on humans. However, he expressed optimism that the current difficulties could be overcome in ten years and that reproductive technology for same-sex couples would eventually become available.

“If people want it and society accepts such technologies, I agree,” said the Japanese scientist. However, he seemed to have doubts about the method used by a man to create a child from his own sperm and artificially created eggs. “Technically it is possible,” he said. “But I’m not sure if it’s something safe or socially acceptable at this stage.”

Method followed

The method involves taking a skin cell from a male rodent and turning it into a pluripotent stem cell that can turn into other types of cells. These cells, like male cells, have XY chromosomes. The researchers then remove the Y chromosome from those cells, duplicate the Xs, and finally “glue” the two Xs together. This allows the stem cell to be reprogrammed to become an egg.

The cells are then grown into an ovarian organoid that mimics conditions in mouse ovaries. When the eggs were fertilized with sperm, 600 embryos were created, from which seven mice were eventually born (low success rate of about 1%). However, these rodents looked healthy and had a normal lifespan, and they themselves had offspring.

This method can also help infertile opposite-sex couples in which the woman is unable to produce her own eggs due to a serious problem such as Turner syndrome (missing one copy of the X chromosome). But it will be years before (and if) such a new fertility treatment becomes available. Other scientists say a ten-year time horizon is too optimistic, given that viable human eggs from female cells have yet to be created in the lab.

^{Source: APE-MEB}