A SINGLE injection could cure obesity and type-2 diabetes, scientists say.

The virus-based drug makes DNA produce more of a metabolism-controlling hormone, tests on fat mice showed.

Skipping insulin injections is risky and could cause blindness, coma and even deathThey lost weight and had less insulin resistance, which causes diabetes.

It also saw them get old more healthily and prevented age-related weight gain. It will be tested on larger animals and then humans.

Veronica Jimenez, head of the Barcelona study, said: “Results show it is safe and effective.”

Colleague Prof Fatima Bosch said it paved the way “to treat diabetes, obesity and related diseases”.