The end of men is at hand as mice are born to two mothers
Scientists unveil world’s first mammals with parents of same sex in advance that may also apply to humans
IT IS perhaps not the news that men wanted to hear. Scientists have discovered that females can reproduce on their own, meaning men could eventually become obsolete.
In a discovery that gripped the scientific community yesterday, the birth was revealed of the world’s first mammals born to two mothers.
A team at the Chinese Academy of Sciences stunned geneticists by revealing they had effectively rewritten the rules of reproduction.
The breakthrough came in the form of 29 mice successfully born to samesex, female parents. Not only were the animals born healthy, but they went on to have babies themselves.
A similar experiment using two male parents failed, however, with the pups dying within days of being born.
In achieving the successful births, the researchers proved they had identified and overcome the factor that makes joint male-female involvement in reproduction essential for humans.
Commentators said the study could pave the way for same-sex human couples to reproduce, although this would not come any time soon.
Mammals can produce offspring only through sexual reproduction usthe ing a female egg fertilised by male sperm. But not all of the natural world uses the same process. Some female birds, reptiles, fish and amphibians are able to reproduce alone, with hammerhead sharks and Komodo dragons some of the more colourful examples. Chinese team set out to identify the genetic process that takes place at the point of mammalian conception that demands genes from both sexes.
They focused on a phenomenon known as “imprinting”, where for roughly 100 genes, only the copy that comes from the mother or only the copy that comes from the father ever becomes “switched on”.
In human embryos, the male genes make up for the females ones that are not switched on and vice versa.
It means an embryo made up of same-sex genes will effectively have some missing.
To overcome this barrier, the scientists obtained some embryonic stem cells from a female mouse and used the gene-editing Crispr-cas9, which has been likened to a genetic pair of scissors, and were able to remove maternal imprinting by “snipping” out a single letter of genetic code from three crucial regions. The edited stem cells were then injected into the egg of a second female mouse, which successfully formed an embryo: 210 embryos were created to yield the 29 live mice.
Qi Zhou, co-senior author, said: “This research shows us what’s possible. We saw that the defects in bimaternal mice can be eliminated and that bipaternal reproduction barriers in mammals can also be crossed through imprinting modification.”
Dr Teresa Holm, from the University of Auckland, said there was a chance in the longer term that the technique could be developed to apply to humans. “[The research] may even lead to the development of ways for same-sex couples to reproduce healthy children of their own,” she said, although she pointed to “significant ethical and safety concerns that would need to be overcome”.
‘It may even lead to the development of ways for same-sex couples to reproduce healthy children of their own’