Lipoprotein(a) Concentration and Apolipoprotein(a) Size

Despite more than 3 decades of intense scientific researchthat has fostered our understanding of the structure andbiochemistry of lipoprotein(a) [Lp(a)], the physiopatho-logical role of Lp(a) is still poorly understood. Consequently, despite its recognition as a risk factor for coronary artery disease (CAD), the role of Lp(a) in atherogenesis and the extent to which Lp(a) levels should be assessed in clinical practice remain controversial. Lp(a), which is the most complex and poly-morphic of the lipoprotein particles, is formed by an LDL moiety and a unique protein, apo(a), linked to apolipoprotein (apo) B-100 of LDL.1 The most intriguing feature of apo(a) is that it shares an extensive structural homology with plasmino-gen, a key proenzyme of the fibrinolytic cascade. Kringle V and the protease domains of apo(a) share.85 % amino-acid identity with the corresponding plasminogen domains, even though the protease domain of apo(a) does not appear to have a catalytic function. Apo(a) contains 10 different types of a sequence with