Does the contraceptive for cats based on gene therapy work

Gene therapy could replace the surgical sterilization of our four-legged friends: its effectiveness and long-term safety has been demonstrated on cats by researchers at the Massachusetts General Hospital in Boston, who publish the results of the trial in Nature Communications.

During some studies on fertility preservation in cancer patients, researchers led by David Pépin have discovered that it is possible to prevent ovulation and conception by increasing the level of anti-Mullerian hormone (naturally produced by both the ovaries in females and the testes in males). In 2017 the team was the first to demonstrate the contraceptive potential of this hormone in rodents and in light of the results obtained decided to expand the experimentation to female domestic cats.

The gene therapy protocol used involves the introduction of a slightly revised version of the feline gene for anti-Müllerian hormone through a viral vector similar to those already approved for clinical use in humans. "A single injection causes the cat's muscles to produce the hormone, which is usually only produced by the ovaries, and increases the level of the hormone by about 100 times compared to the normal level," explains Pépin.

The therapy was given to six cats using two different dosages: after more than two years of monitoring, none of the treated cats had kittens, unlike three other untreated control cats. Ovulation suppression had no impact on other major hormones such as estrogen and no side effects were observed.