Scientists in Texas have created baby mice from two males, raising possibilities that double-father offspring could, in the future, repopulate vulnerable species.
Dr. Richard Behringer at the University of Texas M.D. Anderson Cancer Center published his study Wednesday in the peer-review journal Biology of Reproduction.
The advance could some day even help same-sex human couples have children carrying both parents' genes.
"These findings have novel implications for mammalian production and assisted-reproductive technology," the researchers wrote in the study.
The researchers first cloned a mother mouse from a male. The female carrying the male DNA then mated with another male. The offspring therefore carried genes contributed entirely from two males.
From one male mouse, the scientists produced an "induced pluripotent stem cell line," reprogramming the adult male’s cells so they could enter an embryonic state.
Some cells from this line dropped their Y chromosome during natural cell division, resulting in XO cells.
The scientists then injected those XO cells into surrogate mother mice, which gave birth to babies whose cells still carried one X chromosome from the original male mouse.
When the female babies grew and mated with regular male mice, they therefore produced offspring — both male and female — that showed genetic contributions from two fathers.
The authors of the study called their findings "a new form of mammalian reproduction" and suggested that in a variation, "it may also be possible to generate sperm from a female donor and produce viable male and female progeny with two mothers."