What do endangered species and same-sex couples have in common? Last week, scientists reported findings in the journal Biology of Reproduction that could have implications for both down the line — creating a baby with genetic information from two dads and no mom.
The study, led by scientists at the MD Anderson Cancer Center in Texas, produced mouse babies using genetic material from two male mice, eliminating the mouse mom DNA. The babies even grew up normally and went on to mate themselves and produce healthy babies. Here’s how it worked, and what it could mean for the future of reproductive biology:
The crux of the breakthrough was that the researchers manipulated adult cells to return back into an embryonic stem cell state.
The scientists took a cell from a male mouse and reprogrammed it to become a stem cell (which later gives rise to all tissues in the body). When the cells started to grow, some naturally lost their “Y” chromosome.
(Quick biology 101 reminder: males have XY chromosomes, females have two Xs)
They took the cells that had lost a Y chromosome and injected them into an early stage embryo (blastocyst).
Some of the resulting offspring — even females — had only genetic material from the two males in the equation (the original male, and the one used to create the embryo). The female mice were then mated with male mice, creating a two-dad mouse with no genetic information from a mom.
So you need a womb, but you can work around mom DNA.
This is a trickier thing to pull off in humans, for many reasons. For one, when human embryos inherit only an X chromosome, they often don’t survive. There are plenty of barriers (both biological and ethical) that would make the translation to humans tough — and if it happens, it would be far in the future.