The scientific community has heard the buzz about RNA Interference (RNAi) — a clever trick that allows scientists to silence certain genes in certain locations. Really, it’s a tremendous boon to research, and potentially a lifesaving new tool against cancer and infection.
But now scientists are using it to control behavior. And they’ve started by making female mice less receptive to sex:
Scientists are developing RNAi-based therapies for macular degeneration, cancer, and HIV, and have also used RNAi to study genetic pathways in lower organisms such as worms and fruit flies. But this is one of the first uses of the technique to study such a complex behavior as mating in living mammals.
The hormone estrogen provokes a reaction in female mice called lordosis, which is an arching of the spine in preparation for mating. This behavioral response is mediated in the brain by estrogen receptor alpha (ER-alpha), which sits on the surface of cells and binds to estrogen when it passes through the bloodstream.
Previous work has shown that mice engineered to lack ER-alpha do not exhibit lordosis and aggressively reject males when the males try to mate with them. However, these knockout mice are missing the gene throughout life in every cell of the body, which makes it difficult to pinpoint exactly how the gene governs the mating behavior.
The study published online this week in Proceedings of the National Academy of Sciences uses RNAi to show that one brain region and one gene are completely responsible for the female sexual response in mice.