A team at deCODE genetics in Reykjavik, Iceland has looked at hundreds of thousands of single-letter DNA variations to examine how imprinting* affects the risk of disease.

They identified at least five variations whose correlation with a certain disease depended on whether the gene is maternal or paternal.

They also found disease-linked variants that other studies had missed. One of these boosts a person’s risk of type 2 diabetes by 41 per cent, but only if they inherit it from the father.

*A process that determines which of a parent’s genes are expressed in the child.