蒙古族人群载脂蛋白(a)五核苷酸重复序列基因多态性与脑梗死的关系

Relationship between pentanucleotide repeat polymorphism of apolipoprotein(a)gene and cerebral infarction in Mongolian

目的研究载脂蛋白(a)[apo(a)]5′调控区(TTTTA)n五核苷酸重复序列(PNR)基因多态性在内蒙古地区蒙古族脑梗死患者中的分布特点。方法采用聚合酶链反应-聚丙烯酰胺凝胶电泳(PCR-PAGE)方法检测66例蒙古族健康人群及67例蒙古族脑梗死患者的apo(a)的PNR基因多态性。结果脑梗死患者血浆脂蛋白(a)[Lp(a)]、三酰甘油(TG)水平明显高于健康对照组,高密度脂蛋白-C(HDL-C)水平明显低于健康对照组;脑梗死患者组检测出(TTTTA)序列重复次数为5、8、9共3种等位基因,5/5、5/8、5/9、8/8、8/9、9/9共6种基因型;健康对照组检测出(TTTTA)序列重复次数为5、7、8、9共4种等位基因,5/8、5/5、7/9、8/8、8/9、9/9共6种基因型。两组人群均以重复次数为8和基因型8/8分布频率最高;脑梗死组与健康对照组apo(a)PNR比较发现各等位基因及基因型频率间差异无统计学意义;脑梗死组基因型8/8与8/9间的血浆Lp(a)水平比较差异无统计学意义。结论蒙古族人群apo(a)PNR基因多态性可能与脑梗死发生不存在直接的相关性。

Objective To investigate the relationship between pentanucleotide repeat （PNR） polymorphism of apolipoprotein（a） gene and cerebral infarction in Mongolian. Methods PNR polymorphism of the apo（a） gene from 66 healthy persons and 67 patients with cerebral infarction were analyzed by polymerase chain reaction-polyacrylam- ide gel electrophoresis-silver stain（PCR PAGE）. Results The concentrations of Lp（a） and TG in cerebral infarction patients were significantly elevated compared with normal subjects. However, HDL-C was obviously decreased. In cerebral infarction patients,there were 3 alleles, which wereS,8 and 9 repeats. Moreover, we detected 6 apo（a） PNR genetypes, which were 5/5,5/8,5/9,8/8,8/9 and 9/9. In control group, 4 alleles were detected, namely 5,7,8 and 9. At the same time, we found 6 genetypes, they were 5/8,5/5,7/9,8/8,8/9 and 9/9. Among them,8 repeats and gene- types 8/8 had the highest distribution frequency. The frequency of apo（a） PNR alleles and genetypes had no signifi- cant difference between cerebral infarction patients and controls. Conclusion Perhaps,apo（a） PNR polymorphisms have no direct relationship with cerebral infarction in Mongolian.