心肌梗死患者及同胞载脂蛋白(a)基因5’端多态性的研究

Pentanucleotide repeat polymorphism in 5’ control region of apo(a) gene among myocardial infarction patients and their siblings

关键词:  心肌梗死  同胞  载脂蛋白(a)  脂蛋白(a)

Key words:  myocardial infarction  siblings  apolipoprotein (a)  lipoprotein (a)

摘要:

［目的］研究载脂蛋白(a)基因5’端启动子五核苷酸重复序列（PNR）数目与Lp(a)水平及心肌梗死（MI）的关系。［方法］对59例男性MI 患者、78例同性别同胞和60例年龄、性别相匹配的健康人行临床检查，并从分子遗传学角度行apo(a)基因5’端PNR数目的检测，研究其与Lp(a)水平及心肌梗死发病的关系。［结果］MI组Lp(a) （602±583）mg/L，同胞组（423±365）mg/L，均显著高于对照组（156±144）mg/L（P<0.01），且MI组更高于同胞组（P<0.01）。载脂蛋白(a)基因5’端PNR扩增产物中观察到五种等位基因，MI组和同胞组PNR-8发生率最高（63.6%和34.6%），对照组PNR-10最常见（40.8%）。PNR8/8基因型MI的患病危险为非8/8基因型者的8.09倍（P<0.01），PNR9/8基因型MI的患病危险为非9/8基因型者的30.20倍（P<0.01）。MI组和同胞组PNR平均-8、8.5基因型Lp(a)水平显著高于对照组（P<0.01）。［结论］apo(a)基因5’端PNR数目与Lp(a) 水平及MI发病密切相关，PNR-8/8基因型可能是MI的一个预测因子。

Abstract:

［Objective］To detect the relationship between the pentanucleotide repeat (PNR) size polymorphism in the 5' control region of apolipoprotein (a) [apo(a)] gene and serum Lp(a) level together with myocardial infarction(MI).［Methods］clinical examination were conducted to 59 male MI patients, 78“healthy” male siblings and 60 healthy persons matched in age and sex. Their PNR size polymorphism in the 5' control region of apo(a) gene were determined by molecular biological methods.［Results］The mean Lp(a) levels in MI and sibling group were (602±583) mg/L and (423±365)mg/L, respectively, which were significantly higher than that in the control group (156±144 )mg/L（P<0.01）, moreover ,the Lp(a) level in the MI group was even higher than the sibling group（P<0.01）.Among three groups, five alleles were detected. The eight-repeat allele was the commonest in MI group and the sibling group（63.6%,34.6%），while that in the control group was the ten-repeat allele (40.8%）. The MI relative risk of PNR8/8 was 8.09 times of the non-PNR8/8 genotype（P<0.01）and that of PNR9/8 was 30.20 times of the non-PNR9/8 genotype（P<0.01）. Serum Lp(a) levels of PNRmean -8,8.5 in MI group and the sibling group were significantly higher than those in the control group（P<0.01）.［Conclusions］The PNR size in the 5’ control region of apo(a) gene was closely related to serum Lp(a) level and the incidence of MI. PNR-8/8 genotype may be a predictive factor for MI.