Scottish researchers have made a breakthrough as they identified a gene that could help explain the causes of mental illness.

The international team of scientists, led by experts at Edinburgh University, discovered the gene ABCA13 that may help create drugs to restore mental health in patients with psychiatric illness.

Lead researcher Douglas Blackwood, Professor of Psychiatric Genetics at Edinburgh University found that the gene was faulty more frequently in patients with mental illness, when compared to healthy people.

"This is an exciting step forward in our understanding of the underlying causes of some common mental illnesses. These risk genes could signpost new directions for treatments," the Scotsman quoted him as saying.

Dr Ben Pickard, part of the Edinburgh team, now of Strathclyde University, also said: "This study is the first to identify multiple points of DNA damage within a single gene that are linked with psychiatric illness.

"It strongly suggests that this gene may regulate an important part of brain function that is linked with these devastating disorders."

He continued: "There are several very interesting things that come from this work. The first is that we have got a gene and an inkling about what it might do.

"It seems to be responsible for transporting lipids - various types of fat molecules - around and we suppose that if it fails to transport one particular type, it could have a knock-on affect on a particular aspect of cell function or the way that cells communicate with one another.

"The second thing is the fact that we find these mutations in this gene cropping up in people with schizophrenia, bipolar disorder and depression."