Fatty food trips a genetic switch in the body that can trigger diabetes, a study has found.

Understanding the biological pathway could lead to a potential cure for the disease, say scientists.

The discovery helps explain why Type 2 diabetes is so often linked to obesity.

In studies of mice and humans, researchers found that high levels of fat disrupted two key proteins that turn genes on and off.

The “transcription factors” FOXA2 and HNF1A activate a pancreatic enzyme that in healthy people prevents diabetes developing.

When the proteins stop working, the enzyme is shut down. This in turn upsets the ability of insulin-secreting beta cells in the pancreas to monitor blood sugar levels.

Without this glucose sugar-sensing mechanism, blood sugar cannot be regulated properly.

Study leader Jamey Marth, medical doctor from the Sanford-Burnham Medical Research Institute in the US, said: “Now that we know more fully how states of over-nutrition can lead to Type 2 diabetes, we can see more clearly how to intervene. “The identification of the molecular players in this pathway to diabetes suggests new therapeutic targets and approaches towards developing an effective preventative or perhaps curative treatment.

“This may be accomplished by beta cell gene therapy or by drugs that interfere with this pathway in order to maintain normal beta cell function.”

The research has been published in the journal Nature Medicine.