An active component of the contraceptive "mini-Pill" can reverse a genetic eye condition that normally leads to blindness, research by Irish scientists has shown.
The study, conducted in mice modelling the human disease retinitis pigmentosa, showed that the drug norgestrel could "rescue" light-detecting retinal cells.
The synthetic progestin hormone allowed mice which should have gone blind to retain their sight.
Professor Tom Cotter, who led the team from University College Cork, said: "The drug seems to work by stimulating the production of a protein survival factor called FGF from neighbouring cells in the eye and this helps the light-detecting cells to survive and the animals to see.
"FGF binds to the surface of the light-detecting cells and sends a signal to their DNA to up-regulate strong cells' survival pathways.
"In other words, it 'beefs up' the cells, makes them stronger and better able to resist the destructive effects of the damaged gene that causes the disease.
"At the moment, we still don't know if the drug will also work in humans."
A new study is now planned for next year to see if humans experience the same protective effects as the mice got.
The research is published today in The Journal Of Neurochemistry.
The research is being extended to other eye conditions such as glaucoma, which is a common degenerative condition in people over 60.