Talmud P J, Barni N, Kessling A M, Carlsson P, Darnfors C, Bjursell G, Galton D, Wynn V, Kirk H, Hayden M R
Charing Cross Sunley Research Centre, Hammersmith, London, U.K.
Atherosclerosis. 1987 Sep;67(1):81-9. doi: 10.1016/0021-9150(87)90267-x.
We have investigated the frequencies of 3 restriction fragment length polymorphisms (RFLPs) of the apolipoprotein B (apo B) gene in normo- and hyperlipidaemic individuals. In individuals with type III hyperlipidaemia, the allele frequency for the RFLP detected with XbaI was significantly different from the allele frequency in normolipidaemic individuals and in those with other types of hyperlipidaemia. No significant difference in allele frequency was found among these groups for the RFLPs detected with MspI or EcoRI. Within a sample of 62 normolipidaemic individuals, homozygotes for the X2 allele (cutting site) of the XbaI RFLP had a significantly higher serum cholesterol level than homozygotes for the XI allele, with individuals of the genotype X1X2 having an intermediate value (X2X2 mean 5.71 mmol/l, X1X1 mean 4.81 mmol/l, X1X2 mean 5.30 mmol/l). There were also significant differences in serum triglyceride levels in individuals with different XbaI genotypes. In these normolipidaemic individuals there was no correlation between the EcoRI and MspI RFLP genotypes and levels of any serum lipid variable. Information from the XbaI and EcoRI RFLPs was used in conjunction to define apo B haplotypes. These haplotypes are a more precise measure of the genotypic variation, and they explain a greater fraction of the serum cholesterol and triglyceride levels than the single-site polymorphisms considered separately. This study suggests that variations in the gene for apo B are associated with the determination of serum cholesterol and triglyceride levels both in patients with type III hyperlipidaemia and in the normal population.
我们研究了载脂蛋白B（apo B）基因的3种限制性片段长度多态性（RFLP）在血脂正常和血脂异常个体中的频率。在Ⅲ型高脂血症患者中，用XbaI检测到的RFLP的等位基因频率与血脂正常个体及其他类型高脂血症患者的等位基因频率显著不同。对于用MspI或EcoRI检测到的RFLP，这些组之间未发现等位基因频率有显著差异。在62名血脂正常个体的样本中，XbaI RFLP的X2等位基因（切割位点）的纯合子血清胆固醇水平显著高于XI等位基因的纯合子，基因型为X1X2的个体胆固醇水平处于中间值（X2X2平均为5.71 mmol/l，X1X1平均为4.81 mmol/l，X1X2平均为5.30 mmol/l）。不同XbaI基因型个体的血清甘油三酯水平也存在显著差异。在这些血脂正常的个体中，EcoRI和MspI RFLP基因型与任何血清脂质变量水平之间均无相关性。结合XbaI和EcoRI RFLP的信息来定义apo B单倍型。这些单倍型是对基因型变异更精确的衡量指标，与单独考虑的单一位点多态性相比，它们能解释更大比例的血清胆固醇和甘油三酯水平。这项研究表明，apo B基因的变异与Ⅲ型高脂血症患者和正常人群的血清胆固醇及甘油三酯水平的测定有关。
