亚甲基四氢叶酸还原酶基因MTHFR多态性与唐氏综合征风险的相关性研究  

Correlation between MTHFR polymorphism of methylenetetrahydrofolate reductase and the risk of Down’s syndrome

作　　者：柴鸥[1] 侯志敏[1] CHAI Ou;HOU Zhimin(Department of Obstetrics and Gynecology,Tianjin People’s Hospital,Tianjin 300190,China)

机构地区：[1]天津市人民医院妇产科,300190

出　　处：《河北医药》2020年第6期879-881,885,共4页Hebei Medical Journal

摘　　要：目的研究叶酸代谢相关基因-亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)基因多态性与唐氏综合征高危风险之间的关系。方法采用化学发光法对150例受试孕中期女性血清中甲胎蛋白(AFP)、人类绒毛膜性腺激素(β-HCG)和游离雌三醇(uE3)进行检测,并评估胎儿患唐氏综合征的风险;通过聚合酶链反应(PCR)对所有受试者MTHFR的C677T和A1298C位点进行检测,分析患唐氏综合征高、低危风险2组间MTHFR C677T和A1298C的分布频率及等位基因频率的差异,并构建唐氏综合征低风险的优势单体型。结果唐氏综合征的高、低危组中,MTHFR C677T和A1298C不同基因型和等位基因频率,差异有统计学意义(P<0.05)。高危组中孕妇血清β-HCG的含量高于低危组,而AFP和uE3的含量小于低危组,差异有统计学意义(P<0.05)。单体型分析发现“C-C”型是唐氏综合征低风险的优势单体型,而“C-C”或“T-C”单体型则具有较高的风险,OR值分别为4.177和4.207。结论叶酸代谢酶-亚甲基四氢叶酸还原酶MTHFR C677T和A1298C的基因多态性可能与唐氏高危风险具有一定相关性,携带有“C-C”或“T-C”单体型孕妇可能增大唐氏综合征产前筛查阳性的风险。Objective To investigate the correlation between the gene polymorphism methylenetetrahydrofolate reductase(MTHFR)and the high risk of Down’s syndrome.Methods The serum levels of alpha-fetoprotein(AFP),β-human chorionicgonadotrophin(β-HCG)and unconjugated oestriol(uE3)were detected by chemiluminescence in 150 pregnant women during the second trimester of pregnancy,and the risk of Down's syndrome was assessed.And the C677T and A1298C loci of MTHFR in all the subjects were detected by polymerase chain reaction(PCR).The differences of distribution frequencies and allele frequencies of MTHFR C677T and A1298C were analyzed and comapred between the high risk group and low risk group,moreover,the dominant haplotype with low risk of Down’s syndrome was established.Results There were significant differences in the distribution frequencies and allele frequencies of MTHFR C677T and A1298C between high risk group and low risk group(P<0.05).The serum levels ofβ-HCG in high-risk group were significantly higher than those in low-risk group,however,the serum levels of AFP and uE3 in high-risk group were significantly lower than those in low-risk group(P<0.05).Haplotype analysis showed that“C-C”type was the dominant type with low risk of Down’s syndrome,while“C-C”or“T-C”type had higher risk,OR values was 4.177 and 4.207,respectively.Conclusion The gene polymorphisms of MTHFR C677T and A1298C may be correlated with the high risk of Down’s syndrome,and the pregnant women with“C-C”or“T-C”haplotypes may have higher risk of positive Down’s syndrome in prenatal screening for Down’s syndrome.

关 键 词：唐氏综合征 叶酸 基因多态性 亚甲基四氢叶酸还原酶 

分 类 号：R394.114[医药卫生—医学遗传学]