Scientists in Calgary and Korea have managed to reverse Type 1 diabetes in rodents by using a new type of gene therapy.

Dr. Ji-Won Yoon at the University of Calgary and Dr. Hyun Chul Lee of Korea modified a human gene and placed it into the livers of mice. The gene forced the liver to work like a pancreas and produce a product just like insulin.

Insulin is needed to regulate blood sugar levels in humans. In Type 1 diabetics, the pancreas produces little or no insulin, and patients need to inject it to ensure their blood sugar levels remain stable.

The rats and mice in the study had insulin - made in the pancreas - and their blood sugar levels were normal within one or two weeks of the treatment. Five months later, they were still free of diabetes.

Until now, the insertion of an insulin-producing gene into the body has been unsuccessful. Inserted genes have failed to function reliably over time, to regulate blood glucose levels and to produce insulin.

The researchers say they are still a long way from trying this on people, but Yoon says this discovery is one of the high points of his career. "We expect this breakthrough to pave the way for us to develop a future therapy which, we hope, will cure diabetes in people."

The study results are published in the latest edition of the journal, Nature.