同型半胱氨酸及其胱硫醚酶β-合成酶G919A基因多态性与颅内动脉粥样硬化性狭窄的相关性研究

Relationship between the homocysteine levels and cystathionine beta-synthase G919A gene polymorphisms and intracranial atherosclerotic stenosis

目的探讨胱硫醚酶β-合成酶(CBS)G919A基因多态性与同型半胱氨酸(Hcy)及颅内动脉粥样硬化性狭窄的关系。方法对348例急性脑梗死患者行颅内血管MRA检查。采用PCR-限制片段长度多态性技术和扩增阻滞突变体系法检测患者CBS G919A基因多态性,并使用全自动生化仪采用循环酶法测定其血浆Hcy浓度。结果 348例急性脑梗死患者被纳入研究,其中合并颅内动脉狭窄186例,无颅内动脉狭窄162例。其中CBS G919A基因为纯合突变型(AA)33例(9.4%)、杂合突变型(GA)135例(38.8%)、野生型(GG)180例(51.7%)。纯合突变型患者血浆Hcy水平显著高于杂合突变型及野生型患者(t=9.15,P<0.05;t=8.67,P<0.05);杂合突变型患者血浆Hcy水平显著高于野生型患者(t=6.89,P<0.05)。狭窄组与非狭窄组基因型及等位基因频率差异均无统计学意义(χ^2=1.29,P>0.05;χ^2=0.55,P>0.05)。结论 CBS G919A基因型与血浆Hcy水平相关,但与颅内动脉粥样硬化性狭窄无关。

Objective To investigate the relationship between gene polymorphisms of cystathionine beta-synthase(CBS) G919A, plasma homocysteine(Hcy) levels and intracranial cerebral arteries atherosclerotic. Methods A total of 348 patients with cerebral infarction were enrolled. Their MRA of the intracranial cerebral arteries had been performed. Their plasma total Hcy concentration were measured using automatic biochemical analyzer with enzymatic cycle detection, CBS G919A gene polyorphisms were ananlyed using PCR-restriction fragment length polymorphism and amplification refractory mutation system. Results A total of 348 cerebral infarction patients were enrolled. In these patients, 186 cases with intracranial cerebral vascular stenosis and 162 cases with no stenosis. Thirty-three of them(9.4%) were homozygous mutant AA genotype of the GBS G919A polymorphism, 135 of them(38.8%) were heterozygous mutation GA genotype, 180 of them(51.7%) were wild type GG genotype. The Hcy level of homozygous mutant AA genotype of CBS G919A type was significantly higher than that in heterozygous mutation GA genotype and the wild type GG genotype(t=9.15, P<0.05;t=8.67, P<0.05);The Hcy level of heterozygous mutation GA genotype was significantly higher than that in wild type GG genotype(t=6.89, P<0.05). The distribution of CBS G919A genotype does not show statistical difference between the group with intracranial cerebral vascular stenosis and the group with non-stenosis(χ^2=1.29, P>0.05), and allele frequency as well(χ^2=0.55, P>0.05). Conclusion CBS G919A genotype is associated with the plasma Hcy concentration, but not with intracranial cerebral arteries atherosclerotic.