In addition, the findings of our current study provide weak evidence that hepcidin, ferritin and the ratio hepcidin/ferritin are causally related to atherosclerosis, which confirms the extended ‘iron hypothesis’ and results of our observational study that indicated that the iron distribution, as determined by serum hepcidin and the ratio hepcidin/ferritin, plays a role in the development of atherosclerosis. Here, HAMP is linked to atherosclerosis.