A new breakthrough in egg cell creation has enabled a female mouse to give birth to babies carrying only the genes of two fathers.
Scientists genetically engineered this by turning male XY chromosomes into female XX chromosomes and creating eggs from strictly male skin cells.
“The mice look fine — they grew up to be adults, and the adult mice are also fertile,” says Katsuhiko Hayashi, a genome biologist at Osaka University in Japan.
The achievement has huge implications for same-sex parenting, and for treating or preventing sexual chromosome disorders such as infertility and Down syndrome.
“It was surprising — I’m happy to get these results,” Hayashi says.
