cardiovascular disease ( cvd ) remains the leading cause of death in developed countries , despite the decline of cvd mortality over the last two decades . from observational , predictive research 
 , efforts have been made to find causal risk factors for cvd . 
 however , in recent years , some of these findings have been shown to be mistaken . 
 possible explanations for the discrepant findings are confounding and reverse causation . genetic epidemiology has tried to address these problems through the use of mendelian randomisation . in this paper , we discuss the promise and limitations of using genetic variation for establishing causality of cardiovascular risk factors .