Researchers from California Institute of Technology in US used an adeno-associated virus (AAV) - a small, harmless virus that is unable to replicate on its own - to deliver a gene that directs muscle cells to produce an antibody that neutralises gonadotropin-releasing hormone (GnRH) in mice.
GnRH is what the researchers refer to as a "master regulator of reproduction" in vertebrates - it stimulates the release of two hormones from the pituitary that promote the formation of eggs, sperm, and sex steroids. Without it, an animal is rendered infertile.
In the new study, researchers saw that the mice - both male and female - were unable to conceive after about two months, and the majority remained infertile for the remainder of their lives.
"Inhibiting GnRH is an ideal way to inhibit fertility and behaviours caused by sex steroids, such as aggression and territoriality," said Bruce Hay, professor at Caltech.
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His team also shows that female mice can be rendered infertile using a different antibody that targets a binding site for sperm on the egg.
Hay's team has dubbed the new approach "vectored contraception" and said that there are many other proteins that are thought to be important for reproduction that might also be targeted by this technique.
"Spaying and neutering of animals to control fertility, unwanted behaviour, and population numbers of feral animals is costly and time consuming, and therefore often doesn't happen," said Hay.
"There is a strong desire in many parts of the world for quick, nonsurgical approaches to inhibiting fertility. We think vectored contraception provides such an approach," he said.