亚甲基四氢叶酸还原酶基因C677T多态性及同型半胱氨酸与高脂血症的关联性

目的探讨亚甲基四氢叶酸还原酶基因(MTHFR)C677T多态性及血浆同型半胱氨酸（Hcy）水平与高脂血症的关联性。方
法收集1591例研究对象，采用聚合酶链式反应-限制性片段长度多态性（PCR-RFLP）技术检测MTHFR C677T基因多态性，采
用酶循环法检测血浆Hcy，同时检测血脂水平，按血脂水平将研究对象分组，其中高脂血症组694例，健康对照组897例，比较两
组MTHFR C677T基因多态性及血浆Hcy的差异。统计工具采用SPSS17.0统计软件。结果高脂血症组的MTHFR C677T基
因CC、CT、TT三种基因型频率和C、T两种等位基因频率，以及血浆Hcy水平与健康对照组比较差异无显著性意义（P>0.05）。
CC、CT、TT三种不同MTHFR C677T基因型的血浆Hcy水平差异有极显著性意义（P<0.01），而六种血脂水平差异无显著性意
义（P>0.05）；通过进一步两两比较结果显示，TT基因型的血浆Hcy水平与CC、CT基因型比较差异有极显著性意义（P<0.01），
TT基因型的血浆Hcy 水平明显高于CC、CT基因型；而CC基因型的血浆Hcy 水平与CT基因型比较差异无显著性意义（P>
0.05）。结论MTHFR C677T基因多态性和血浆Hcy水平两者与高脂血症均不具关联性，而MTHFR C677T基因多态性与血浆
Hcy水平显著相关，TT基因型的血浆Hcy水平明显高于CC、CT基因型。

Association of C677T gene polymorphisms of methylenetetrahydrofolate reductase and plasma homocysteine level with hyperlipidemia

Objective To study the association of methylenetetrahydrofolate reductase (MTHFR) gene C677T mutation and
plasma homocysteine (Hcy) levels with hyperlipidemia. Methods Blood samples were collected from 1591 adults for detecting
MTHFR gene C677T polymorphism with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP),
plasma Hcy levels with enzymatic cycling method, and blood lipid levels as well. The patients were divided according to the
lipid levels into hyperlipidemia group (n=694) and healthy control group (n=897) and the differences in MTHFR gene C677T
polymorphisms and plasma Hcy levels were compared. Results The hyperlipidemia group and healthy control group showed
no significant differences in CC, CT, or TT genotype frequencies or C and T allele frequencies of MTHFR C677T gene, and had
comparable plasma Hcy levels (P>0.05). Patients with 3 different MTHFR C677T genotypes had significant differences in
plasma Hcy levels (P<0.01) but not in blood lipid levels (P>0.05). Pairwise comparison indicated a significantly higher plasma
Hcy level in TT genotype than in CC and CT genotypes (P<0.01), and the latter two genotypes showed no significant difference
(P>0.05). Conclusion MTHFR C677T polymorphisms and plasma Hcy levels are closely related but neither of them is
associated with hyperlipidemia. The TT genotype is associated with a significantly higher plasma Hcy level than CC and CT
genotypes.