The findings were published today in the Nature and Nature Genetics science journals. One of the study's authors, Professor Bryan Mowry, said while it was too early to develop genetic testing for schizophrenia, the findings were a major advance in scientists' understanding of the illness.

Previously, there was no evidence of a genetic link to the disease. "Schizophrenia is a devastating illness causing delusions, hallucinations and impairing social and cognitive behaviour," he said. Professor Mowry said the study, as well as similar concurrent studies overseas, "represent a landmark step forward in the effort to uncover the genetic basis for schizophrenia, with the hope to develop better treatment - hopefully in the near future".

He said the Queensland team had celebrated its success but was now back at work, expanding on its research. Professor John McGrath, Queensland schizophrenia expert and head of the Queensland Brain Institute's schizophrenia group at the University of Queensland, praised the researchers for their "backbreaking work", which had led to a greater understanding of the brain disorder.

"If you think about the human genetic code as a huge instruction manual, some mistakes involve tiny, single letter typographical errors within the word," he said. "Another type of mistake may involve deleting a whole paragraph, or repeating a sentence twice. "The three papers published this week have reported findings that both of these types of genetic mutations increase the risk for schizophrenia."

In Australia, approximately seven in every 1000 people will be diagnosed with some form of schizophrenia in their lifetime.