• Journal of Preventive Medicine and Public Health
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• 제38권4호
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• pp.437-442
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• 2005

Objectives : DNA methylation is one of the best characterized epigenetic mechanisms that play a regulatory role in genome programming and imprinting during embryogenesis. In this present study, we investigated the association between DNA methylation in the human placenta and the maternal folate and homocysteine concentrations on the Methylenetetrahydrofolatereductase (MTHFR) genetic polymorphism during pregnancy. Methods : We investigated 107 pregnant women who visited Ewha Woman's University Hospital for prenatal care during their $24{\sim}28$ weeks-period of gestation. During the second trimester, we measured the serum homocysteine and folate concentrations . The MTHFR 677 genetic polymorphism was determine by performing PCR-RFLP assay. The expression of DNA methylation in the human placentas was estimated by using immunohistochemistry method. Results : Serum folate was negatively correlated with the serum homocysteine concentration for all the MTHFR genotypes. We found positive correlation between the folate concentrations and the DNA methylation in the human placenta (p<0.05). An increasing concentration of homocysteine was associated with reduced DNA methylation in the human placenta. The coefficient value was -2.03 (-3.77, -0.29) on the regression model (p<0.05). Conclusion : These findings suggest that the maternal folate and homocysteine levels along with the MTHFR 677 genetic polymorphism during pregnancy affect the DNA methylation in the human placenta.

• Journal of Genetic Medicine
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• 제5권2호
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• pp.119-124
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• 2008

목 적: 다운증후군을 비롯한 염색체의 수적이상은 태아의 유산이나 정신박약의 가장 큰 요인으로 알려져 있다. 이에 본 연구에서는 엽산 대사에 관련된 효소의 다형성(MTHFR C677T, MTRR A66G)을 조사하여 태아의 염색체 수적이상과 유전적인 연관성을 알아보고자 한다. 대상 및 방법: 염색체 수적이상이 확인된 태아를 임신한 37명의 산모와 유산이나 비정상적인 임신을 한 경험이 없고 2명 이상의 건강한 아이를 출산한 78명의 여성을 정상군으로 하여 혈액으로부터 DNA를 추출하고 PCR-RFLP를 이용하여 각 지역의 다형성 여부를 확인하였다. 결 과: MTHFR C677T 유전자형은 CC, CT, TT에 대해 각각 30.7%, 48.7%, 20.6%였으며, 환자군에서 각각 37.8%, 48.6%, 13.5% 였다. 정상군과 환자군 사이 모든 조합에서 유의한 차이를 보이지 않았다. 대립유전자의 비율 역시 대조군과 환자군에서 각각 44.9%, 37.8%였으며, 통계적 유의한 차이는 없었다. MTRR A66G 유전자형은 대조군에서 AA, AG, GG에 대해 각각 50.0%, 46.1%, 3.9%였으며, 환자군에서는 각각 13.5%, 81.1%, 5.4%였다. MTRR의 정상 유전자형인 AA와 이형접합성 변이형인 AG 유전자형을 비교하였을 때 유의한 차이를 보였으며(OR: 6.5, 95% CI: 2.3-18.6, P<0.05), 정상이 아닌 모든 다른 유전자형(AG/GG)과 비교하였을 때에도 역시 유의한 차이를 보였다(OR: 6.4, 95% CI: 2.3-18.1, P<0.05). 결 론: 본 연구에서는 MTHFR 677번째 염기의 다형성은 염색체 비분리로 인한 태아 염색체의 수적이상과 연관성이 없는 것으로 확인하였으나, MTRR 66부위의 경우 염기의 다형성이 태아 염색체의 수적이상을 유발하는 유전적 요소로서의 가능성을 제시하고 있다.

• Genomics & Informatics
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• 제5권2호
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• pp.56-60
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• 2007

Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common craniofacial birth defect that is the result of a mixture of genetic and environmental factors. While studies have identified a number of different candidate genes and loci for the etiology of CL/P, the results have not been consistent among different ethnic groups. To study the genetic association of the candidate genes in Korean patients affected by CL/P, we genotyped 97 nonsyndromic CL/P patients and 100 control individuals using single nucleotide polymorphic markers at the MTHFR, TGFA, and IRF6 genes. We report that the T3827C marker at TGFA showed significant association with nonsyndromic CL/P, but all the other markers tested were not significantly associated with nonsyndromic CL/P in Korean patients.

• 대한유전성대사질환학회지
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• 제11권1호
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• pp.103-105
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• 2011

고호모시스틴혈증(hyperhomocysteinemia)은 호모시스테인과 메티오닌의 대사과정에 관여하는 여러 효소들의 결핍에 의해 발생할 수 있으며, 대표적인 효소 결핍으로는 cysthathione beta-synthase (CBS) 결핍증, Methionine synthase (MS) 결핍증, methylenetetrahydrofolate reductase (MTHFR) 결핍증이 있다. 이들은 고호모시스테인혈증을 보이나 임상증상, 메티오닌의 동반 상승, 거대적아구성빈혈, 메칠말로닌산뇨증등의 동반 여부등을 토대로 감별진단에 도움을 받을 수 있다. 본 연자는 뇌혈전증과 뇌졸중을 동반하는 고호모시스테인혈증의 원인으로 MTHFR 유전자의 돌연변이를 발견한 증례를 경험하였기에 이를 보고하는 바이다.

• Clinical and Experimental Pediatrics
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• 제54권8호
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• pp.335-339
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• 2011

Purpose: Hyperhomocysteinemia is known as a risk factor for atherosclerosis. Preclinical arteriosclerosis is noted and premature atherosclerosis is known to be accelerated in Kawasaki disease (KD) patients. Genetic polymorphisms in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene result in elevated plasma homocysteine concentrations and are known to be associated with the development of coronary artery disease. Our hypothesis is that single nucleotide polymorphisms (SNPs) of the MTHFR gene are related to the development of KD and coronary artery lesions (CALs). Methods: For this study, we selected 3 candidate single nucleotide polymorphisms (SNPs) (rs2274976, rs1801131, and rs1801133) of MTHFR. These SNPs are located on chromosome 1p36.3. We included 101 KD patients and 306 healthy adults as controls in this study. CALs were seen in 38 patients. Genotypes of the selected SNPs were determined by direct sequencing and analyzed with SNPAlyze. Results: The genetic distribution and allelic frequency of the 3 MTHFR SNPs (rs2274976, rs1801131, and rs1801133) were not significantly different in patients with KD compared to the control group (P=0.71, 0.17, and 0.96, respectively). There was no difference in the genetic distribution of the MTHFR SNPs between the normal control group and the CAL group (P=0.43, 0.39, 0.52 respectively). Conclusion: The genetic distribution of the MTHFR SNPs (rs2274976, rs1801131, and rs1801133) was not different in the KD group compared to the control group. In addition, the genetic distribution of these SNPs was not different in the CAL group compared to the control group in the Korean population.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4559-4565
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• 2013

Background: Methylenetetrahydrofolate reductase (MTHFR) is involved in DNA synthesis and repair. We here aimed to investigate two common polymorphisms, C677T and A1298C, with genotype and haplotype frequencies in colorectal cancer (CRC) cases among Jordanian. Materials and Methods: 131 CRC cases were studied for MTHFR C677T and A1298C polymorphisms, compared to 117 controls taken from the general population, employing the PCR-RFLP technique. Results: We found the frequency of the three different genotypes of MTHFR C677T among Jordanians to be CC: 61.7%, CT: 35.2%, and TT 3.1% among CRC cases and 50.9%, 38.8% and 10.3% among controls. Carriers of the TT genotype were less likely to have CRC (OR=0.25; 95%CI: 0.076-0.811; p=0.021) as compared to those with the CC genotype. Genotype analysis of MTHFR A12987C revealed AA: 38.9%, AC: 45%, and CC 16% among CRC cases and 37.4%, 50.4% and 12.2% among controls. There was no significant association between genetic polymorphism at this site and CRC. Haplotype analysis of MTHFR polymorphism at the two loci showed differential distribution of the TA haplotype (677T-1298A) between cases and controls. The TA haplotype was associated with a decreased risk for colorectal cancer (OR=0.6; 95% CI: 0.4-0.9, p=0.03). Conclusions: The genetic polymorphism of MTHFR at 677 and the TA haplotype may modulate the risk for CRC development among the Jordanian population. Our findings may reflect an importance of genes involved in folate metabolism in cancer risk.

• Clinical and Experimental Reproductive Medicine
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• 제38권3호
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• pp.168-173
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• 2011

Objective: To examine the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and hyperhomocysteinemia in women with unexplained recurrent miscarriages (RM) and to investigate the association between MTHFR genotype variants and alloimmune activation, proportion of peripheral blood natural killer (pbNK) cells. Methods: A total of 39 patients with a history of two or more unexplained miscarriages were recruited to this study. The controls were women who had a live birth without a history of RM (n=50). The proportion of pbNK cells was measured by flow cytometry. Plasma homocysteine levels and the incidence of the MTHFR variant of the RM and control groups were compared. The proportion of pbNK cells was compared to the MTHFR variants in the RM group. Results: No differences were found between the two groups' mean plasma homocysteine levels ($7.6{\pm}1.5{\mu}mol$/L vs. $7.1{\pm}2.1{\mu}mol$/L) or incidence of the MTHFR genotype variant (CC, 35% vs. 33%; CT, 40% vs. 53%; and TT, 25% vs. 14%). In the RM group, individuals with the TT variant ($7.7{\pm}1.1{\mu}mol$/L) had higher homocysteine levels than those with the CC and CT variants ($7.4{\pm}1.9{\mu}mol$/L and $7.4{\pm}1.2{\mu}mol$/L) and those with the CT variant ($19.2{\pm}8.1%$) had a higher proportion of CD3-/CD56+ pbNK cells than those with the CC and TT variants ($17.7{\pm}6.6%$ and $17.9{\pm}7.0%$), but the results of both comparisons were statistically insignificant. Conclusion: These preliminary results show no difference in plasma homocysteine levels between the RM and control groups or among MTHFR genotype variants in the RM group, which may suggest that the plasma homocysteine level is difficult to use as a predictive marker of RM in the Korean population. A study of a larger number of patients is needed.

• Clinical and Experimental Reproductive Medicine
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• 제44권3호
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• pp.152-158
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• 2017

Objective: To identify the associations between polymorphisms of the 3'-untranslated region (UTR) of methylenetetrahydrofolate reductase (MTHFR) gene, which codes for an important regulatory enzyme primarily involved in folate metabolism, and idiopathic recurrent pregnancy loss (RPL) in Korean women. Methods: The study population comprised 369 RPL patients and 228 controls. MTHFR 2572C > A, 4869C > G, 5488C > T, and 6685T > C 3'-UTR polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis or by TaqMan allelic discrimination assays. Natural killer cell proportions were determined by flow cytometry. Results: The MTHFR 2572-5488-6685 (A-C-T) haplotype had an adjusted odds ratio of 0.420 (95% confidence interval, 0.178-0.994; p= 0.048) for RPL. Analysis of variance revealed that MTHFR 4869C > G was associated with altered $CD56^+$ natural killer cell percentages (CC, $17.91%{\pm}8.04%$; CG, $12.67%{\pm}4.64%$; p= 0.024) and folate levels (CC, $12.01{\pm}7.18mg/mL$; CG, $22.15{\pm}26.25mg/mL$; p= 0.006). Conclusion: Variants in the 3'-UTR of MTHFR are potential biomarkers for RPL. However, these results should be validated in additional studies of ethnically diverse groups of patients.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 2002년도 제54차 추계 학술대회 연제집
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• pp.362-363
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• 2002

• Journal of Nutrition and Health
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• 제38권3호
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• pp.211-218
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• 2005

Elevated homocysteine concentration is known to be related to placental abruption, spontaneous abortion, and many adverse pregnancy outcomes. The purpose of this study was to investigate the effects of folic acid supplementation ($1000{\cal}ug$ per day) and 5, 10 methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism genotype on serum homocysteine and B vitamin levels in 50 infertile women ($31.2{\pm}3.2\;years$). Blood sampling was performed at baseline and at the end of folic acid supplementation period. In infertile women, serum folate and vitamin $B_{12}$ concentrations were significantly higher in post-supplementation than those in pre-supplementation. Serum homocysteine concentration was significantly lower in post-supplementation than that in pre-supplementation. However, serum homocysteine levels were still higher in the T/T genotype than those in the C/C or C/T even after folic acid supplementation. Serum homo-cysteine was inversely related to serum folate in T/T homozygotes at baseline and at the end of folic acid supplementation. These results suggest that folic acid supplementation is needed for infertile women to improve their vitamin status and also to reduce the risk of hyperhomocysteinemia. These effects were different according to their MTHFR C677T genotypes. Therefore, further studies are necessary to determine the optimal level of supplementation of folic acid by MTHFR genotypes.