Within the apolipoprotein A-I-C-III-A-IV gene cluster, the Ssti polymorphism in the 3' untranslated region of the apolipoprotein C-III gene is the variant site most consistently and strongly associated with raised plasma triglyceride levels and coronary artery disease. To date the molecular mechanisms that underlie this effect have not been fully identified and variation within the insulin-responsive element of the apolipoprotein C-III proximal promoter cannot entirely explain the Ssti effect.