Baby mice born from male mouse cells
Baby mice (File photo)
Scientists have created eggs using the cells of male mice for the first time, resulting in seven pups from two fathers, according to a study published Wednesday in the journal Nature.
The tested technique is still a long way from being used in humans, due, among other things, to a very low success rate and numerous questions of concern. x27;ethics.
But this breakthrough has implications for reproduction, with the possibility for male couples, or even a single male, to have a biological child without the help of any help. ;a female egg.
The study is the result of research by a Japanese team of developmental biologist Katsuhiko Hayashi, of the University of Kyushu.
The team had already found a way to turn skin cells from a female mouse into a usable egg to give birth to healthy pups.
This time she tried the same experiment from a male mouse, taking skin cells from its tail, then turning them into what are called pluripotent stem cells. That is, capable of transforming into any cell type.
As in humans, male mouse cells have pairs of XY chromosomes, and those of females of XX pairs.
During the process, the researchers obtained about 6% of cells losing the Y chromosome which gives them the male character, and then duplicated the remaining X chromosome, to obtain the XX pair, specific to the female subject.
The transformed cells were used to create egg cells, fertilized with male mouse sperm, and then implanted into the uterus of surrogate female mice.
Seven pups were born, out of a total of 630 trials, resulting in a success rate of less than 1%. The pups are healthy and fertile.
M. Hayashi, who presented his study last week at the 3rd International Summit on Human Genome Editing in London, warned that many hurdles remain ahead of human experiments.
Nitzan Gonen, director of the gender determination lab at Israel's Bar-Ilan University, spoke to AFP about a groundbreaking study.
< p class="e-p">The technique would theoretically allow a two-man couple to have a child, with one providing the sperm and the other the egg, according to Dr. Gonen. A single man could even provide the sperm and egg, which he says is a bit like cloning, like that of the sheep Dolly, the first mammal cloned from an adult cell in 1996.
Jonathan Bayerl and Diana Laird, two reproduction and stem cell experts at the University of California, San Francisco, explained in Nature that there is no guarantee that the experiment will be successful from of human stem cells.
But they called the study a remarkable milestone in reproductive biology. With a potential use to save an endangered species that has only one breeding male left.
For his part, Nitzan Gonen considers the procedure very ineffective, with 99% of embryos not surviving.
It would be even more problematic in humans, where the nine-month gestation time , compared to only three weeks in mice, would increase the risk of failure. Beyond the technical questions arise ethical questions. The fact of being able to do something does not necessarily mean that one must do it […] particularly when one speaks of a species of human being, commented the Israeli researcher.