Want to get rid of grey or white hair permanently? Desmond Tobin may be your man.

The 32-year-old Irish scientist already greying at the temples says he is in the early stages of a discovery that could make going grey a thing of the past.

He cautions it will be years before a lotion might appear on store shelves, but he has a vision of a liquid that is rubbed into the scalp to bring back natural colour.

Mr. Tobin, working originally at the New York University medical centre and, since Christmas, at Bradford University in England, has found that colour comes out of hair because pigment cells in follicles under the skin go to sleep.

More excitingly, he has found a way to kick-start these cells and restore colour to the hair.

Hair goes grey or white when the cells that produce pigment called melanocytes become worn out, at an age determined by your genetic clock. But the follicles of grey and white hairs retain a reservoir of sleeping melanocytes, and Mr. Tobin has figured out a way to get those dormant cells to start making pigment again.

It is very tough to put a time frame on it, but it will be at least 10 years before we have a product, he said yesterday. To say it would be shorter would be too optimistic. We have to go through toxicity, efficacy and drug trials and that takes a long time. This is early days.

Mr. Tobin, who is the first scientist to grow hair follicles in a test tube, said he also needs to find something you can rub on that properly penetrates the skin so it can go to work on the follicles below.

I haven t even thought about how much this could be worth, he said. What he has discovered so far is in the public domain, so he hasn't patented anything.

Mind you, if our subsequent developments are successful, we would have to consider our actions very carefully.