Cardoso-Saldaña G, De La Peña-Díaz A, Zamora-González J, Gomez-Ortega R, Posadas-Romero C, Izaguirre-Avila R, Malvido-Miranda E, Morales-Anduaga M E, Anglés-Cano E
Instituto Nacional de Cardiología Ignacio Chávez, Mexico, D.F.
Ann Hum Biol. 2006 Mar-Apr;33(2):202-12. doi: 10.1080/03014460500520006.
Lp(a) is a lipoparticle of unknown function mainly present in primates and humans. It consists of a low-density lipoprotein and apo(a), a polymorphic glycoprotein. Apo(a) shares sequence homology and fibrin binding with plasminogen, inhibiting its fibrinolytic properties. Lp(a) is considered a link between atherosclerosis and thrombosis. Marked inter-ethnic differences in Lp(a) concentration related to the genetic polymorphism of apo(a) have been reported in several populations.
The study examined the structural and functional features of Lp(a) in three Native Mexican populations (Mayos, Mazahuas and Mayas) and in Mestizo subjects.
We determined the plasma concentration of Lp(a) by immunonephelometry, apo(a) isoforms by Western blot, Lp(a) fibrin binding by immuno-enzymatic assay and short tandem repeat (STR) polymorphic marker genetic analysis by capillary electrophoresis.
Mestizos presented the less skewed distribution and the highest median Lp(a) concentration (13.25 mg dL(-1)) relative to Mazahuas (8.2 mg dL(-1)), Mayas (8.25 mg dL(-1)) and Mayos (6.5 mg dL(-1)). Phenotype distribution was different in Mayas and Mazahuas as compared with the Mestizo group. The higher Lp(a) fibrin-binding capacity was found in the Maya population. There was an inverse relationship between the size of apo(a) polymorphs and both Lp(a) levels and Lp(a) fibrin binding.
There is evidence of significative differences in Lp(a) plasma concentration and phenotype distribution in the Native Mexican and the Mestizo group.
脂蛋白(a)[Lp(a)]是一种功能未知的脂蛋白，主要存在于灵长类动物和人类中。它由低密度脂蛋白和载脂蛋白(a)[apo(a)]组成，后者是一种多态性糖蛋白。apo(a)与纤溶酶原具有序列同源性并能结合纤维蛋白，抑制其纤溶特性。Lp(a)被认为是动脉粥样硬化和血栓形成之间的一个联系。在几个人群中，已报道Lp(a)浓度存在显著的种族间差异，这与apo(a)的基因多态性有关。
本研究检测了墨西哥三个原住民群体（马约人、马扎瓦人、玛雅人）以及混血人群中Lp(a)的结构和功能特征。
我们采用免疫比浊法测定血浆Lp(a)浓度，采用蛋白质免疫印迹法检测apo(a)异构体，采用免疫酶法检测Lp(a)纤维蛋白结合能力，并通过毛细管电泳进行短串联重复序列(STR)多态性标记基因分析。
与马扎瓦人（8.2 mg/dL）、玛雅人（8.25 mg/dL）和马约人（6.5 mg/dL）相比，混血人群的分布偏差最小，Lp(a)浓度中位数最高（13.25 mg/dL）。与混血人群相比，玛雅人和马扎瓦人的表型分布有所不同。玛雅人群中Lp(a)的纤维蛋白结合能力更高。apo(a)多态体的大小与Lp(a)水平及Lp(a)纤维蛋白结合均呈负相关。
有证据表明，墨西哥原住民和混血人群在Lp(a)血浆浓度和表型分布方面存在显著差异。
