Valenti K, Aveynier E, Laporte F, Hadjian A J
Laboratoire de Biochimie A, Centre Hospitalier, Universitaire de Grenoble, France.
Clin Chim Acta. 1997 Jul 25;263(2):249-60. doi: 10.1016/s0009-8981(97)00066-1.
Apoprotein (a) size polymorphism was evaluated at the genotypic and phenotypic level in 110 individuals. Both methods were well correlated with respect to size (r = 0.971), providing that the protein size was expressed as a number of kringle 4 repeats. Despite the fact that the immunoblotting method used was sensitive enough to detect less than 1 ng of lipoprotein (a), 62 samples had single-band phenotypes and one sample had no detectable band, whereas only seven samples had single-band genotypes. The mean size of the alleles coding for the undetected isoforms was significantly larger (141 kb) than for the detected isoforms (123 kb), corroborating the earlier finding of an inverse relationship between the size and the plasma expression level of apoprotein (a). Furthermore, increasing detectability was achieved by loading the gel with different amounts of plasma for each sample. Our results indicate that genotyping is more resolving and more sensitive, but requires a more specialized technology. Phenotyping was carried out using commercially available reagents.
在110名个体中，从基因型和表型水平评估了载脂蛋白(a)的大小多态性。如果将蛋白质大小表示为kringle 4重复序列的数量，两种方法在大小方面相关性良好(r = 0.971)。尽管所使用的免疫印迹方法灵敏度足以检测到少于1 ng的脂蛋白(a)，但62个样本具有单带表型，1个样本未检测到条带，而只有7个样本具有单带基因型。编码未检测到的异构体的等位基因的平均大小(141 kb)明显大于检测到的异构体(123 kb)，这证实了先前关于载脂蛋白(a)大小与血浆表达水平之间呈负相关的发现。此外，通过为每个样本在凝胶上加载不同量的血浆，提高了检测能力。我们的结果表明，基因分型更具分辨率和灵敏度，但需要更专业的技术。表型分析使用市售试剂进行。
