T polymorphism of the MTHFR gene and variant hemoglobins : a study in newborn (original) (raw)

C677T polymorphism of the MTHFR gene and variant hemoglobins: a study in newborns from Salvador, Bahia, Brazil

Cadernos de Saúde Pública, 2004

The C677T polymorphism in the methylenetetrahydrofolate reductase gene (MTHFR) is associated with an increase in total homocysteine serum levels (tHcy), described as a risk factor for cardiovascular disease. Eight hundred forty-three neonates from two different maternity hospitals, one public and another private, in Salvador, Bahia, Brazil were screened for this polymorphism by PCR and RFLP. The T-allele frequency in the total sample was 0.23, and the prevalence rates of heterozygous and homozygous carriers were 36.2% and 5.3%, respectively. The T-allele frequency differed and the T/T genotype was more prevalent at the private maternity hospital. The hemoglobin (Hb) profile was investigated by HPLC in 763 newborns. The frequency of variant Hb was higher at the public than at the private maternity hospital. The association of the C677T polymorphism and the Hb profile was investigated in 683 newborns, showing a relatively high frequency of variant Hbs and the T allele. These data coul...

Investigation the Association Between MTHFR Gene Polymorphism and Homocysteine in Iranian Pregnant Women

Asian Journal of Pharmaceutical and Clinical Research, 2017

Objective: This study was aimed to investigate the association between polymorphisms in MTHFR gene and Vitamin B12-dependent homocysteine metabolism.Methods: Hyperhomocysteinemia has been implicated as a risk factor for complications in pregnancy including abortion, preeclampsia, and placental abruption. Several epidemiological studies have investigated the associations of MTHFR C677T polymorphism with hypertension or hypertension in pregnancy. However, the results were controversial. Numbers of 100 samples from healthy pregnant women as control criteria and 100 samples from fertile women have been collected. Due to research on MTHFR polymorphism, special primers have been designed. The research on MTHFR polymorphism has been done by restriction fragment length polymorphism assay.Results: The results demonstrated 9.26% have been registered for heterozygous individuals and the homocysteine level of homozygous individuals was 41.18% (higher than the normal level). The results showed...

Homocysteine, Folate & Methylenetetrahydrofolate Reductase (MTHFR) 677C???T Polymorphism in Spanish Pregnant Woman and in Their Offspring

Journal of Pediatric Gastroenterology and Nutrition, 2005

In the present study, the determinants of fasting plasma homocysteine in diabetic subjects were examined; whether plasma homocysteine and vascular disease are related and the influence of the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene on serum and erythrocyte folate, plasma homocysteine and vascular disease. Diabetic clinic subjects (Type I, n l 354; Type II, n l 392) were recalled for a cross-sectional survey. Standard methods were used to measure biochemical variables and to characterize vascular disease and MTHFR genotype. Plasma homocysteine was significantly and directly related to age, male sex and serum urea, and inversely related to serum folate and vitamin B12, independently in stepwise regression. When corrected for age and sex, homocysteine was significantly related to hard end points of coronary artery disease and stroke (each P 0.01), remaining significant when additionally adjusted for serum folate (P l 0.043 and P l 0.019 respectively). Serum folate was not clearly related to these events, although there was a trend to associate with the lower quintile of serum folate. The MTHFR genotype was not a determinant of plasma homocysteine, even in those in the lowest quintile of serum folate, nor of vascular disease. TT homozygosity at residue 677 was associated with elevation of total erythrocyte folate compared with both other genotypes (P 0.0001), almost certainly due to the diversion of 5,10-methylenetetrahydrofolate into derivates subsequent to the partial metabolic block that results from the MTHFR enzyme defect. In conclusion, in this clinic cohort of people with diabetes, vascular disease is related to plasma homocysteine, which is correlated with serum folate. The MTHFR genotype does not significantly influence either plasma homocysteine or vascular disease, despite it being a determinant of erythrocyte folate, which reflects its effect on folate metabolism.

Plasma Homocysteine Levels, Methylene Tetrahydrofolate Reductase Polymorphisms, and the Risk of Thromboembolism in Children

Journal of Pediatric Hematology/Oncology, 2011

There are limited data regarding the role of methylene tetrahydrofolate reductase (MTHFR) A1298C polymorphism and hyperhomocysteinemia as risk factors for retinal vein thrombosis (RVT) in Iranians. This study aimed to examine a possible association between fasting plasma total homocysteine (tHcy) levels, MTHFR A1298C polymorphism and RVT development in Iranian patients. Our study population consisted of 73 patients with a diagnosis of RVT (52.7 W 16.2 years) and 73 age and sex-matched healthy controls (49.1 W 14.6 years). Genotyping for the MTHFR A1298Cpolymorphism was conducted by PCR-RFLP technique and plasma tHcy levels were measured by an enzyme immunoassay method. Fasting plasma tHcy levels were 20.29 W 8.5 mmol/l in RVT patients and 10.9 W 3.1 mmol/l in control subjects. The number of cases with abnormal tHcy values (hyperhomocysteinemia) was significantly higher in the RVT patients than control subjects (P U 0.0001). The prevalence of MTHFR 1298CC homozygote genotype was similar in RVT patients and controls (17.8 vs.15.1%, P U 0.45). There were no significant differences in genotype distribution of MTHFR A1298C polymorphism between males and females in both RVT patients and controls (P > 0.05). The frequency of the 1298C allele was 39.1 and 35.6% in patients and controls, respectively, and did not differ significantly between them (P U 0.23). Moreover, heterozygote and homozygote genotypes in the RVT patients had significantly higher abnormal tHcy values than corresponding genotypes in control subjects (P < 0.001). Our study demonstrated that hyperhomocysteinemia but not homozygosity for MTHFR A1298C polymorphism is a significant risk factor for RVT in the Iranian population. Blood Coagul Fibrinolysis 27:000-000

Association of total plasma homocysteine with methylenetetrahydrofolate reductase genotypes 677C>T, 1298A>C, and 1793G>A and the corresponding haplotypes in Swedish children and adolescents

International journal of molecular medicine, 2007

We studied 692 Swedish children and adolescents (aged 9-10 or 15-16 years, respectively), in order to evaluate the effect of the methylenetetrahydrofolate reductase (MTHFR) 677C>T, 1298A>C, and 1793G>A polymorphisms on total plasma homocysteine concentrations (tHcy). Genotyping was performed with Pyrosequencing™ technology. The MTHFR 677C>T polymorphism was associated with increased tHcy concentrations in both the children and the adolescents (P<0.001 for both age groups) in both genders. The effect of MTHFR 1298A>C was studied separately in subjects with the 677CC and 677CT genotypes, and the 1298C allele was found to be associated with higher tHcy levels both when children were stratified according to 677C>T genotypes, and when using haplotype analyses and diplotype reconstructions. The 1793A allele was in complete linkage disequilibrium with the 1298C allele. It was still possible to show that the 1793A allele was associated with lower tHcy levels, statistically significant in the adolescents. In conclusion, a haplotype-based approach was slightly superior in explaining the genetic interaction on tHcy plasma levels in children and adolescents than a simple genotype based approach (R 2 adj 0.44 vs. 0.40). The major genetic impact on tHcy concentrations is attributable to the MTHFR 677C>T polymorphism. The common 1298A>C polymorphism had a minor elevating effect on tHcy, whereas the 1793G>A polymorphism had a lowering effect on tHcy.

MTHFR C677T and A1298C gene polymorphisms and their relation to homocysteine level in Egyptian children with congenital heart diseases

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/authorsrights Objective: To investigate the association of combined MTHFR C677T and A1298C gene polymorphisms with congenital heart diseases (CHD) in Egyptian children and their mothers and to determine their effect on homocys-teine level in these children. Material and methods: MTHFR C677T and A1298C polymorphisms were genotyped in 160 Egyptian children (80 patients with CHD and 80 healthy controls) and their mothers using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP), while, homocysteine (Hcy) level was measured optically by enzymatic method. Results: We found that MTHFR 677TT genotype, T allele, 1298CC genotype, and C allele were associated with 2.61, 2.0, 2.91 and 1.99 fold increased risk of CHD in Egyptian children respectively. Furthermore, the frequencies of MTHFR 1298AC and CC genotypes and C allele significantly increased in mothers with CHD affected children. The homocysteine levels were significantly increased in MTHFR 677TT and 1298CC genotypes in children with CHD. Conclusions: Our study demonstrated an association of MTHFR A1298C polymorphisms with CHD in Egyptian children and their mothers, while, MTHFR C677T polymorphisms were significantly associated with the risk of CHD in the children only. An association between combined MTHFR A1298C and C677T polymorphisms and CHD was recorded in the children and their mothers. Also, homocysteine levels were significantly increased with both MTHFR 677TT and 1298CC genotypes in Egyptian children with CHD.

Correlation Between C677T and A1298C Mutations on the MTHFR Gene With Plasma Homocysteine Levels and Venous Thrombosis in Pregnant Women at Risk of Thrombosis

Zahedan Journal of Research in Medical Sciences, 2015

Background: Deep venous thrombosis (DVT) is a common disease with a high morbidity, mortality and increase in miscarriages. Objectives: The purpose of this study was to assessment the correlation between C677T and A1298C mutations on the methylenetetrahydrofolate reductase (MTHFR) gene with total plasma homocysteine levels and deep venous thrombosis in pregnant women at risk of thrombosis. Patients and Methods: In this case-control study, 120 pregnant women with risk of DVT and 100 pregnant women without risk of DVT were included in the study. Assay for identification of MTHFR mutations was carried out by PCR-RFLP. Total plasma homocysteine was measured by ELISA method. Results: Homozygous (MM) mutations of MTHFR C677T and A1298C were not associated with DVT in pregnant women with and without DVT, respectively. Plasma homocysteine levels were significantly higher in pregnant women with DVT (18.3 ± 5.9 μmol/L) than in the pregnant women without DVT (8.9 ± 6.4 μmol/L) in C677T and A1298C mutations on the MTHFR gene, respectively (P = 0.021). Conclusions: Our results showed that MTHFR C677T and MTHFR A1289C polymorphisms are not connected with total plasma homocysteine levels in pregnant women with and without DVT. Also, plasma homocysteine levels were significantly higher in pregnant women with DVT.

Polymorphisms in the methylenetetrahydrofolate reductase and methionine synthase reductase genes and homocysteine levels in Brazilian children

American Journal of Medical Genetics, 2004

Hyperhomocysteinemia is a risk factor for thrombosis, and methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms, folate, and B 12 levels could contribute to plasma homocysteine (Hcy) variation. Although well established in adults, few studies have been performed in childhood. In this study, we investigated association of polymorphisms C677T and A1298C in the MTHFR gene and A66G in the MTRR gene with Hcy levels in children. These polymorphisms, as well as Hcy, folate, and vitamin B 12 levels were investigated in 220 normal children with ages ranging from 1 to 8 years. Plasma Hcy, folate, and vitamin B 12 levels were normal in all children. None of the polymorphisms could be considered an independent risk factor for hyperhomocysteinemia during childhood. The median Hcy levels in 37 children (17%) doubly heterozygous for C677T and A1298C mutations in the MTHFR gene were not different from the other genotypes. However, the association of the different genotypes with Hcy, folate, and vitamin B 12 levels demonstrated significant P-values. The folate levels demonstrated a statistically significant decrease (P ¼ 0.0477) from the C677T mutation in the MTHFR gene (TT genotype) when compared to the other groups. Folate was the only independent risk factor for hyperhomocysteinemia. Thus, monitoring the concentrations of folate would be more helpful for evaluating hyperhomocysteinemia and for preventing cardiovascular disease. ß 2004 Wiley-Liss, Inc.

Association of Methylenetetrahydrofolate Reductase C677T Polymorphism with Hyperhomocysteinemia and Deep Vein Thrombosis in the Iranian Population

Vascular specialist international, 2015

Deep venous thrombosis (DVT) is a common but elusive condition characterized by a high morbidity and mortality rate. The aim of the present study was to investigate the correlation between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with plasma total homocysteine (tHcy) levels and DVT risk in an Iranian population. Materials and Methods: Our study population consisted of 67 patients with a diagnosis of DVT and 67 healthy subjects as controls. Genotyping of MTHFR C677T polymorphism was performed by the polymerase chain reaction technique combined with restriction enzyme fragment length polymorphism (PCR-RFLP) and measurement of tHcy levels was done by enzyme immunoassay method. Results: Plasma tHcy levels were significantly higher in DVT patients than controls (18.09±7.6 vs. 10.5±4.3, P=0.001). Also, plasma tHcy levels were significantly higher in MTHFR 677TT genotypes compared to 677CC genotypes in both DVT patients (P=0.016) and controls (P=0.03). Neither heterozygote nor homozygote genotypes of MTHFR C677T polymorphism was significantly correlated with DVT (P>0.05). The distribution of MTHFR C677T genotypes was similar between men and women in both DVT patients and controls (P>0.05). Moreover, the frequency of mutant 677T allele did not differ significantly between the two groups (28.3% vs. 21.6%, P=0.15). Conclusion: Based on this study, we propose that hyperhomocysteinemia but not homozygosity for MTHFR C677T polymorphism is a significant risk factor for DVT in the Iranian population. Also, MTHFR 677TT genotype is a determinant of elevated plasma tHcy levels.