Molecular biology in the diagnosis of cardiovascular diseases]

Genes shown to affect risk factors or protective factors with respect to coronary heart disease (CHD) have been identified at the APOB, APOAI, LPA, LDLR, APOE and CETP loci. Rare mutations (e.g., in the LDLR and APOE genes) may have a major effect, whereas genes belonging to normal polymorphism have only a moderate effect. Even genes with only a slight effect can be clinically important in combination with other genes or life-style factors. There is gene to gene interaction between LDLR and APOE genes. Important risk factors determined by genes as well as by environmental factors are homocystein and fibrinogen. In addition to traditional lipid and apoprotein measurements, the levels of Lp(a) lipoprotein, fibrinogen and homocystein should be examined in connection with diagnosing CHD cases. DNA analyses are appropriate when familial hypercholesterolemia is suspected, and it is likely that the importance of mutation analyses will increase significantly in the near future.