亚甲基四氢叶酸还原酶基因多态性及甲状腺功能与妊娠期糖尿病的相关性

Association of methylene tetrahydrofolate reductase gene polymorphism and thyroid function indicators with gestational diabetes mellitus

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因C677T位点多态性及甲状腺功能与妊娠期糖尿病的相关性。方法选取承德医学院附属医院51名患有妊娠期糖尿病的孕妇作为病例组,同期60名正常妊娠孕妇作为对照组。运用PCR-荧光探针法检测两组的MTHFR C677T基因多态性。采用全自动免疫分析仪进行甲状腺功能指标的测定。应用全自动生化分析仪检测两组研究对象的血浆同型半胱氨酸水平。对比两组孕妇甲状腺功能、同型半胱氨酸和MTHFR基因型分布情况,探讨MTHFR基因多态性及甲状腺功能与妊娠期糖尿病的关系。结果妊娠期糖尿病组与对照组比较,基因型分布差异有统计学意义(P<0.01);妊娠期糖尿病组T等位基因频率为61.76%,C等位基因频率为38.24%,与对照组比较,其差异有显著性(P<0.01)。妊娠期糖尿病组与对照组甲状腺功能和同型半胱氨酸水平比较,其同型半胱氨酸和促甲状腺激素的水平高于对照组,差异有统计学意义(P<0.05)。不同基因型孕妇的甲状腺功能和同型半胱氨酸水平比较,无论是病例组还是对照组内,存在MTHFR基因C677T突变者,其甲状腺功能和同型半胱氨酸水平较无基因突变者有所不同,即TT基因型孕妇和CT基因型孕妇促甲状腺激素和同型半胱氨酸水平较CC基因型孕妇更高,差异有统计学意义(P<0.05)。妊娠期糖尿病组内甲状腺功能与同型半胱氨酸的相关性分析,血清促甲状腺激素水平与血浆同型半胱氨酸水平呈明显正相关(P<0.01)。二元Logistic回归分析结果显示,高水平的促甲状腺激素和同型半胱氨酸是导致孕妇罹患妊娠期糖尿病的重要危险因素。结论MTHFR基因C677T位点多态性、同型半胱氨酸和甲状腺功能可能与妊娠期糖尿病的发生有关,T等位基因、升高的同型半胱氨酸和促甲状腺激素可能是妊娠期糖尿病的重要危险因素。

Objective To investigate the relationship between polymorphism of MTHFR gene C677 T、thyroid function and gestational diabetes mellitus.Methods Fifty-one pregnant women with gestational diabetes in the Affiliated Hospital of Chengde Medical College were selected as the case group and 60 women with normal pregnancy were selected as the control group.The polymorphism of MTHFR C677 Tgene in both groups was detected by PCR-fluorescence probe method.The thyroid function indicators were determined by automatic immune analyzer.The plasma homocysteine levels of the two groups were measured by automatic biochemical analyzer.The thyroid function,homocysteine and distribution of MTHFR genotypes in two groups of pregnant women were compared to investigate the relationship between MTHFR gene polymorphism,thyroid function and gestational diabetes.Results Compared with the control group,the genotype distribution of gestational diabetes group was statistically significant(P<0.01).The T allele frequency and C allele frequency in gestational diabetes group were 61.76%and 38.24%respectively,which were significantly different from the control group(P<0.01).Comparison of thyroid function and homocysteine levels between the gestational diabetes group and the control group showed that the levels of homocysteine and thyroid stimulating hormone were higher in the gestational diabetes group than in the control group,and the differences were statistically significant(P<0.05).Both in the case group and in the control group,thyroid stimulating hormone and homocysteine levels of the pregnant women with TT genotype and CT genotype were higher than those with CC genotype,and the differences were statistically significant(P<0.05).Correlation analysis of thyroid function and homocysteine in gestational diabetes group showed that serum thyroid stimulating hormone level was positively correlated with plasma homocysteine level(P<0.01).Binary Logistic regression analysis showed that high levels of thyroid stimulating hormone and homocysteine were important risk factors for gestational diabetes in pregnant women.Conclusion Polymorphisms of MTHFR gene C677 T,homocysteine and thyroid function may be associated with the development of gestational diabetes,and T alleles,elevated homocysteine and thyroid stimulating hormone may be important risk factors for gestational diabetes.