Genetic epidemiology of dyslipidaemia and atherosclerosis.

The clinical relevance of the heterogeneity in the size and density of low-density lipoprotein (LDL) particles is now widely recognized. The evidence from epidemiological studies, family studies and twins studies demonstrates that small, dense LDL (LDL subclass phenotype B) is a common, genetically influenced risk factor for coronary heart disease (CHD). Several atherogenic mechanisms have been proposed to explain the association of small, dense LDL with CHD, including evidence that small, dense LDL is an integral feature of the insulin resistance syndrome. Furthermore, a recent study in elderly Finnish men and women has shown that phenotype B prospectively predicts non-insulin-dependent diabetes mellitus (NIDDM). In addition, ongoing studies of large Japanese-American kindreds will provide valuable data for evaluating small, dense LDL as a marker for genetic susceptibility to both CHD and NIDDM in a high-risk ethnic group.