Funke H, Rust S, Assmann G
Clin Chem. 1986 Jul;32(7):1285-9.
An oligonucleotide "melting" procedure was developed whereby we can monitor for a sequence heterogeneity in the gene for apolipoprotein E production. Two oligonucleotides were synthesized, one recognizing the common epsilon 3 allele but not the common epsilon 2 allele, the other recognizing the epsilon 2 allele but not the epsilon 3 allele. Samples from 15 subjects with different apolipoprotein E phenotypes as classified by isoelectric focusing were analyzed by this method for the presence of an Arg----Cys substitution in position 158 of the apolipoprotein E amino acid sequence. In 14 of these subjects the genotype determined by oligonucleotide melting agreed with the phenotype identified by isoelectric focusing. In one patient, however, whose phenotype was E2/2 by isoelectric focusing, the DNA hybridized with both oligonucleotides. We conclude that this patient has a mutation in one of his alleles for apolipoprotein E that differs from the frequently seen Arg----Cys change. The apolipoprotein E gene may thus be more heterogeneous than previously anticipated.
我们开发了一种寡核苷酸“熔解”程序，通过该程序可以监测载脂蛋白E产生基因中的序列异质性。合成了两种寡核苷酸，一种识别常见的ε3等位基因，但不识别常见的ε2等位基因，另一种识别ε2等位基因，但不识别ε3等位基因。采用该方法对15名经等电聚焦分类的具有不同载脂蛋白E表型的受试者样本进行分析，以检测载脂蛋白E氨基酸序列第158位是否存在精氨酸→半胱氨酸替代。在这些受试者中，有14名通过寡核苷酸熔解确定的基因型与通过等电聚焦鉴定的表型一致。然而，在一名经等电聚焦鉴定表型为E2/2的患者中，其DNA与两种寡核苷酸均杂交。我们得出结论，该患者的一个载脂蛋白E等位基因发生了突变，该突变不同于常见的精氨酸→半胱氨酸变化。因此，载脂蛋白E基因的异质性可能比之前预期的更高。
