A common nonsense mutation in the repetitive Kringle IV-2 domain of human apolipoprotein(a) results in a truncated protein and low plasma Lp(a).

LPA, the gene coding for apolipoprotein(a) [apo(a)], is the major determinant of lipoprotein(a) [Lp(a)] plasma levels, which are associated with risk for coronary heart disease (CHD) and stroke. It is not completely understood how variation in LPA relates to Lp(a) concentrations. One type of variation related to Lp(a) levels is the number of Kringle (K) IV-2 (g.

Hyperhomocyst(e)inemia is an important risk factor for vascular disease in subjects with high-molecular weight apo(a) isoforms.

Background: Homocyst(e)ine is reported to increase the binding of lipoprotein(a) [Lp(a)] to fibrin, which may increase the thrombogenic effects of Lp(a) in vivo. The aim of this study was to investigate whether there is a relationship between homocyst(e)ine and Lp(a) levels and vascular disease risk, and if the relationship depends on the apo(a) isoforms.

Methods: A case-control study was performed in 91 Caucasian male subjects with vascular disease due to athersclerosis, and in 100 healthy age- and sex-matched control subjects.