A team of researchers has managed to reproduce viable mouse offspring from same-sex couples, thanks to a new technique that uses modified stem cells erasing chemical groups of DNA associated with sex. This is the first time this method has been applied successfully, after previous research that used other techniques to reproduce offspring from same-sex couples. The study has been published this Thursday in the magazine Cell Stem Cell.
Many species of animals are capable of reproducing with methods that do not require a male-female couple, as it happens with reptiles, amphibians and fish. But the process is more complicated in the case of mammals. "We were interested in the question of why mammals can only experience sexual reproduction," study co-author Qi Zhou of the Chinese Academy of Sciences told the magazine.
The study developed a complicated process of genetic manipulation with which they eliminated abnormalities generated in the reproductive process of same-sex couples. Mammals usually inherit two sets of genes, one from the mother and another from the father. But a chemical group of DNA associated with sex, the so-called "genetic imprint," is inherited from a single parent.
In this case, the subset of the other parent is inactive, since when transmitting it it is turns off. If the process of off It does not work properly, breeding can suffer anomalies or even die. Mixing genetic material from same-sex couples presents the risk of babies receiving two sets of genetic imprints.
Using two sets of DNA from female mice, the scientists managed to produce 29 offspring from 210 embryos, which managed to live to adulthood and reproduce normally. But mice produced from two sets of male genetic material barely survived 48 hours
The study used haploid embryonic stem cells, which resemble the "original germ cells, the precursors of the ovules and sperm," explained another co-author, Baoyang Hu. Then they altered the composition of the cells, erasing the "regions with genetic imprints" to mimic the "off" process that occurs in normal reproduction.
Using two sets of DNA from female mice, with genetic manipulations, the scientists managed to produce 29 offspring from 210 embryos, which managed to live to adulthood and reproduce normally. But mice produced from two sets of male genetic material (which were injected into a mouse ovum that had its nucleus removed and, therefore, the female genetic material) barely survived 48 hours. The researchers plan to study why the process did not work.
Dusko Ilic, a stem cell researcher at King's College London, has described the study as "pointer" and believes that it will shed light "on different aspects of mammalian reproduction and opens new doors for future research," he said. SMC agency. "Exploring how to apply similar technologies in the near future to humans is impossible, the risk of severe abnormalities is too high, and it will take many years of research with different animals to know how much they could do safely."
"The authors have taken an extremely important step so that we can understand why mammals only reproduce sexually," says Christophe Galichet, a researcher at the Francis Crick Institute.
Although the applications of this research are largely theoretical, they could improve methods of cloning mammals and even, in the long term, fertility treatments for same-sex couples, the authors say.