In general, men are more insulin resistant and have higher levels of fasting glucose (FG) as defined by impaired fasting glycaemia (FG concentration 5.6–6.9 mmol/l), whereas women are more likely than men to have elevated 2-h glucose concentrations (impaired glucose tolerance, IGT, i.e., 2-h post-challenge glucose concentration 7.8–11 mmol/l) with both measures defining categories of individuals at higher diabetes risk1–3. This evidence concerns the gene INS and diabetes mellitus.