SIXTEEN years after Dolly the sheep was cloned in Edinburgh, scientists in Scotland have made another startling medical breakthrough.

Researchers at Edinburgh's Centre for Regenerative Medicine have created brain tissue from patients suffering mental illnesses such as schizophrenia and depression.

"A patient's neurones can tell us a great deal about the psychological conditions that affect them, but you cannot stick a needle in someone's brain and take out its cells," the centre's director, Professor Charles french-Constant, told the Guardian.

"However, we have found a way round that. We can take a skin sample, make stem cells from it and then direct these stem cells to grow into brain cells. Essentially, we are turning a person's skin cells into brain."

The scientists hope that studying these manufactured brain cells will reveal clues to the conditions of patients with mental illnesses - a task that had been challenging in the past.

"It is very difficult to get primary tissue to study until after a patient has died," said the Royal Edinburgh Hospital's Professor Andrew McIntosh, who is collaborating with the center on the project.

"Even then, that tissue is affected by whatever killed them and by the impact of the medication they had been taking for their condition, possibly for several decades. So having access to living brain cells is a significant development for the development of drugs for these conditions," McIntosh said.

If successful, the same methods could be used for other organs, including the liver and heart.