Pasteur Institute of Iran, Biochemistry Department, Tehran, Iran.
Cancer Epidemiol. 2011 Feb;35(1):56-8. doi: 10.1016/j.canep.2010.10.001. Epub 2010 Nov 2.
Methylenetetrahydrofolate reductase (MTHFR) involves in folic acid metabolism which influences DNA methylation. A single nucleotide polymorphism (SNP) called 677C→T in MTHFR gene causes producing a thermolabile enzyme with reducing function and eventually defects DNA methylation. To determine association between germ-line polymorphism in MTHFR gene with differentiated thyroid carcinoma (DTC), this preliminary study was designed.
This was a case-control study of 154 DTC patients and 198 cancer free individuals. Genotyping was performed by a multiplex PCR method and the frequencies of the 677C→T SNP in cases and controls were compared. The risk estimation was done by multivariate logistic regression analysis.
Compared to CC genotype, an increased risk of DTC for the 677C→T homozygous genotype was demonstrated (odds ratio [OR]: 2.08, 95% confidence interval [CI]: 0.82-5.25). Also, multivariate analysis demonstrated an increased risk of DTC in recessive fashion (TT vs. CC or CT) (OR: 2.38, 95% CI: 0.97-5.82).
The MTHFR 677C→T homozygous variant allele may be associated with increased risk of DTC.
亚甲基四氢叶酸还原酶（MTHFR）参与叶酸代谢，影响 DNA 甲基化。MTHFR 基因中的单核苷酸多态性（SNP）677C→T 导致产生一种热不稳定的酶，其还原功能降低，最终导致 DNA 甲基化缺陷。为了确定 MTHFR 基因种系多态性与分化型甲状腺癌（DTC）之间的关联，进行了这项初步研究。
这是一项 154 例 DTC 患者和 198 例无癌症个体的病例对照研究。采用多重 PCR 方法进行基因分型，比较病例和对照组中 677C→T SNP 的频率。通过多变量逻辑回归分析进行风险估计。
与 CC 基因型相比，677C→T 纯合基因型显示出 DTC 的风险增加（比值比 [OR]：2.08，95%置信区间 [CI]：0.82-5.25）。此外，多变量分析表明，隐性遗传方式（TT 与 CC 或 CT）增加了 DTC 的风险（OR：2.38，95% CI：0.97-5.82）。
MTHFR 677C→T 纯合变异等位基因可能与 DTC 的风险增加相关。
