Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism: epidemiology, metabolism and the associated diseases

Impact of gene-by-trauma interaction in MDD-related multimorbidity clusters

BACKGROUND

Major depressive disorder (MDD) is considerably heterogeneous in terms of comorbidities, which may hamper the disentanglement of its biological mechanism. In a previous study, we classified the lifetime trajectories of MDD-related multimorbidities into seven distinct clusters, each characterized by unique genetic and environmental risk-factor profiles. The current objective was to investigate genome-wide gene-by-environment (G × E) interactions with childhood trauma burden, within the context of these clusters.

METHODS

We analyzed 77,519 participants and 6,266,189 single-nucleotide polymorphisms (SNPs) of the UK Biobank database. Childhood trauma burden was assessed using the Childhood Trauma Screener (CTS). For each cluster, Plink 2.0 was used to calculate SNP × CTS interaction effects on the participants' cluster membership probabilities. We especially focused on the effects of 31 candidate genes and associated SNPs selected from previous G × E studies for childhood maltreatment's association with depression.

RESULTS

At SNP-level, only the high-multimorbidity Cluster 6 revealed a genome-wide significant SNP rs145772219. At gene-level, MPST and PRH2 were genome-wide significant for the low-multimorbidity Clusters 1 and 3, respectively. Regarding candidate SNPs for G × E interactions, individual SNP results could be replicated for specific clusters. The candidate genes CREB1, DBH, and MTHFR (Cluster 5) as well as TPH1 (Cluster 6) survived multiple testing correction.

LIMITATIONS

CTS is a short retrospective self-reported measurement. Clusters could be influenced by genetics of individual disorders.

CONCLUSIONS

The first G × E GWAS for MDD-related multimorbidity trajectories successfully replicated findings from previous G × E studies related to depression, and revealed risk clusters for the contribution of childhood trauma.

Protective alleles and precision healthcare in crewed spaceflight

Common and rare alleles are now being annotated across millions of human genomes, and omics technologies are increasingly being used to develop health and treatment recommendations. However, these alleles have not yet been systematically characterized relative to aerospace medicine. Here, we review published alleles naturally found in human cohorts that have a likely protective effect, which is linked to decreased cancer risk and improved bone, muscular, and cardiovascular health. Although some technical and ethical challenges remain, research into these protective mechanisms could translate into improved nutrition, exercise, and health recommendations for crew members during deep space missions.

MTHFR gene polymorphisms in diabetes mellitus

The methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) are three regulatory enzymes in the folic acid (FA) cycle play a critical role in the balance of methionine and homocysteine. MTHFR and MTRR gene polymorphisms affect the biochemical activities of enzymes, impairing the remethylation of homocysteine to methionine. In 1972, severe MTHFR deficiency resulting in homocystinuria was first reported, suggesting MTHFR involvement in the disease. MTHFR C677T polymorphism can independently increase the risk of high homocysteine (HHcy) in plasma. Elevation of homocysteine levels could increase the risk of microvascular damage, thrombosis, heart disease, etc. Vascular complications were regarded as a leading major cause of diabetes mortality, and disability increases individual health and economic burden. Diabetes mellitus (DM) is a chronic inflammatory disease, and conventional medications do not provide a complete cure for diabetes. It was essential to identify other risk factors for the intervention and prevention of diabetes. MTHFR gene polymorphism is an emerging risk factor in diabetes. Recent studies have shown that polymorphisms of the MTHFR gene play a significant role in the pathophysiology of diabetes, including inflammation and insulin resistance. This review summarizes the association between MTHER gene polymorphism and diabetes.

MTHFR as a Novel Candidate Marker for Litter Size in Rabbits

Litter size is a significant economic trait during animal reproduction. This current study attempted to decipher whether MTHFR promotes the apoptosis of granulosa cells (GCs) and inhibits their proliferation by investigating the effects of the MTHFR gene using flow cytometry and a Cell Counting Kit-8 (CCK-8) assay. MTHFR is linked with ovarian follicle development in the reproductive performance of 104 female New Zealand rabbits. We observed that MTHFR could regulate the mRNA of follicular development-related genes (TIMP1, CITED1, FSHR, GHR, HSD17B1, and STAR) with a qRT-PCR, and we observed the protein expression of CITED1 and GHR using a western blot (WB) analysis. The dual luciferase activity assays helped identify the core promoter region of the MTHFR gene, and the polymorphism of the MTHFR promoter region was studied using Sanger sequencing. The results indicated four single nucleotide polymorphisms (SNPs) within the core promoter region, among which the g.-680C>A locus was significantly associated with both the total and alive litter sizes. Additionally, the CC genotype was associated with the largest total and alive litter sizes, compared to the CA and AA genotypes (p < 0.05). In conclusion, this study investigated the effects of MTHFR on ovarian granulosa cells and its association with selected reproductive parameters in rabbits. The results provide a theoretical foundation for the use of MTHFR as a molecular marker in rabbits.

The Significance of Genetically Determined Methylation and Folate Metabolism Disorders in the Pathogenesis of Coronary Artery Disease: A Target for New Therapies?

Methylation is a biochemical process involving the addition of a methyl group (-CH3) to various chemical compounds. It plays a crucial role in maintaining the homeostasis of the endothelium, which lines the interior surface of blood vessels, and has been linked, among other conditions, to coronary artery disease (CAD). Despite significant progress in CAD diagnosis and treatment, intensive research continues into genotypic and phenotypic CAD biomarkers. This review explores the significance of the methylation pathway and folate metabolism in CAD pathogenesis, with a focus on endothelial dysfunction resulting from deficiency in the active form of folate (5-MTHF). We discuss emerging areas of research into CAD biomarkers and factors influencing the methylation process. By highlighting genetically determined methylation disorders, particularly the MTHFR polymorphism, we propose the potential use of the active form of folate (5-MTHF) as a novel CAD biomarker and personalized pharmaceutical for selected patient groups. Our aim is to improve the identification of individuals at high risk of CAD and enhance their prognosis.

The Multifaceted Complexity of Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS): A Case Report Highlighting Atypical Gastrointestinal Manifestations

BACKGROUND

Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS) is an autosomal dominant autoinflammatory disorder stemming from mutations in the TNFRSF1A gene affecting the tumor necrosis factor receptor (TNFR)-1. These mutations lead to dysregulated inflammatory responses, primarily mediated by augmented interleukin (IL)-1β release.

CASE PRESENTATION

We present the case of a 29-year-old woman with a history of recurrent febrile episodes, abdominal pain, and joint manifestations, eventually diagnosed with TRAPS following genetic testing revealing a heterozygous R92Q mutation in TNFRSF1A. Further genetic examinations unveiled additional clinically significant mutations, complicating the clinical picture. Our patient exhibited delayed colonic transit time and right colonic amyloidosis, a rare complication. Surgical intervention was required for overwhelming intestinal obstruction, revealing mucosal atrophy and dense lymphocytic infiltrates on histological examination.

DISCUSSION

Gastrointestinal involvement in TRAPS is common but can present diagnostic challenges. Following colon resection, histological examination revealed amyloid deposition, underscoring the importance of a comprehensive evaluation of these patients. Isolated colic amyloidosis has significant diagnostic and prognostic implications, warranting cautious monitoring and tailored management strategies. Treatment of TRAPS typically involves anti-inflammatory agents such as IL-1 inhibitors, with our patient experiencing clinical improvement on anakinra and canakinumab.

CONCLUSION

This case report emphasizes the diverse manifestations of TRAPS and the importance of recognizing gastrointestinal complications, particularly isolated colic amyloidosis. Comprehensive evaluation, including histological examination, is crucial for identifying atypical disease presentations and guiding management decisions. Continued research is needed to elucidate the underlying mechanisms and optimize treatment strategies for TRAPS and its associated complications.

Folate and Vitamin B12 Levels in Chilean Women with PCOS and Their Association with Metabolic Outcomes

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age. Many women with PCOS have been found to have an unbalanced diet and deficiencies in essential nutrients. This study aimed to assess the levels of folate and vitamin B12 (B12) and their relationship with metabolic factors in women with PCOS. Anthropometric, clinical, and genetic analyses were conducted to evaluate markers related to one-carbon metabolism in women with PCOS and in a control group. The PCOS group had a higher BMI and HOMA-IR (1.7 vs. 3.1; p < 0.0001). HDL cholesterol levels were 23% lower and triglyceride levels were 74% higher in women with PCOS. Although there were no significant differences in folate and B12 levels between the PCOS and control groups, over 60% of women with PCOS had low B12 levels (<300 pg/mL) and high homocysteine levels. In addition, the MTHFR A1298C and C677T polymorphisms were not associated with PCOS. Moreover, erythrocyte folate levels were positively correlated with fasting glucose, triglycerides, and free androgen index, and negatively correlated with SHBG and LH levels. These results suggest that B vitamins may be associated with the metabolic phenotype in PCOS. This study emphasizes the potential link between folate, vitamin B12, and metabolic and hormonal outcomes in women with PCOS.

Genetic Susceptibility in Endothelial Injury Syndromes after Hematopoietic Cell Transplantation and Other Cellular Therapies: Climbing a Steep Hill

Hematopoietic stem cell transplantation (HSCT) remains a cornerstone in the management of patients with hematological malignancies. Endothelial injury syndromes, such as HSCT-associated thrombotic microangiopathy (HSCT-TMA), veno-occlusive disease/sinusoidal obstruction syndrome (SOS/VOD), and capillary leak syndrome (CLS), constitute complications after HSCT. Moreover, endothelial damage is prevalent after immunotherapy with chimeric antigen receptor-T (CAR-T) and can be manifested with cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). Our literature review aims to investigate the genetic susceptibility in endothelial injury syndromes after HSCT and CAR-T cell therapy. Variations in complement pathway- and endothelial function-related genes have been associated with the development of HSCT-TMA. In these genes, CFHR5, CFHR1, CFHR3, CFI, ADAMTS13, CFB, C3, C4, C5, and MASP1 are included. Thus, patients with these variations might have a predisposition to complement activation, which is also exaggerated by other factors (such as acute graft-versus-host disease, infections, and calcineurin inhibitors). Few studies have examined the genetic susceptibility to SOS/VOD syndrome, and the implicated genes include CFH, methylenetetrahydrofolate reductase, and heparinase. Finally, specific mutations have been associated with the onset of CRS (PFKFB4, CX3CR1) and ICANS (PPM1D, DNMT3A, TE2, ASXL1). More research is essential in this field to achieve better outcomes for our patients.

Dynamic inter-domain transformations mediate the allosteric regulation of human 5, 10-methylenetetrahydrofolate reductase

5,10-methylenetetrahydrofolate reductase (MTHFR) commits folate-derived one-carbon units to generate the methyl-donor S-adenosyl-L-methionine (SAM). Eukaryotic MTHFR appends to the well-conserved catalytic domain (CD) a unique regulatory domain (RD) that confers feedback inhibition by SAM. Here we determine the cryo-electron microscopy structures of human MTHFR bound to SAM and its demethylated product S-adenosyl-L-homocysteine (SAH). In the active state, with the RD bound to a single SAH, the CD is flexible and exposes its active site for catalysis. However, in the inhibited state the RD pocket is remodelled, exposing a second SAM-binding site that was previously occluded. Dual-SAM bound MTHFR demonstrates a substantially rearranged inter-domain linker that reorients the CD, inserts a loop into the active site, positions Tyr404 to bind the cofactor FAD, and blocks substrate access. Our data therefore explain the long-distance regulatory mechanism of MTHFR inhibition, underpinned by the transition between dual-SAM and single-SAH binding in response to cellular methylation status.

A Proactive Intervention Study in Metabolic Syndrome High-Risk Populations Using Phenome-Based Actionable P4 Medicine Strategy

The integration of predictive, preventive, personalized, and participatory (P4) healthcare advocates proactive intervention, including dietary supplements and lifestyle interventions for chronic disease. Personal profiles include deep phenotypic data and genetic information, which are associated with chronic diseases, can guide proactive intervention. However, little is known about how to design an appropriate intervention mode to precisely intervene with personalized phenome-based data. Here, we report the results of a 3-month study on 350 individuals with metabolic syndrome high-risk that we named the Pioneer 350 Wellness project (P350). We examined: (1) longitudinal (two times) phenotypes covering blood lipids, blood glucose, homocysteine (HCY), and vitamin D3 (VD3), and (2) polymorphism of genes related to folic acid metabolism. Based on personalized data and questionnaires including demographics, diet and exercise habits information, coaches identified 'actionable possibilities', which combined exercise, diet, and dietary supplements. After a 3-month proactive intervention, two-thirds of the phenotypic markers were significantly improved in the P350 cohort. Specifically, we found that dietary supplements and lifestyle interventions have different effects on phenotypic improvement. For example, dietary supplements can result in a rapid recovery of abnormal HCY and VD3 levels, while lifestyle interventions are more suitable for those with high body mass index (BMI), but almost do not help the recovery of HCY. Furthermore, although people who implemented only one of the exercise or diet interventions also benefited, the effect was not as good as the combined exercise and diet interventions. In a subgroup of 226 people, we examined the association between the polymorphism of genes related to folic acid metabolism and the benefits of folate supplementation to restore a normal HCY level. We found people with folic acid metabolism deficiency genes are more likely to benefit from folate supplementation to restore a normal HCY level. Overall, these results suggest: (1) phenome-based data can guide the formulation of more precise and comprehensive interventions, and (2) genetic polymorphism impacts clinical responses to interventions. Notably, we provide a proactive intervention example that is operable in daily life, allowing people with different phenome-based data to design the appropriate intervention protocol including dietary supplements and lifestyle interventions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43657-023-00115-z.

Sperm DNA methylation defects in a new mouse model of the 5,10-methylenetetrahydrofolate reductase 677C>T variant and correction with moderate dose folic acid supplementation

5,10-Methylenetetrahydrofolate reductase (MTHFR) is an enzyme that plays a key role in providing methyl groups for DNA methylation, including during spermatogenesis. A common genetic variant in humans (MTHFR 677C>T) results in reduced enzyme activity and has been linked to various disorders, including male infertility. A new animal model has been created by reproducing the human equivalent of the polymorphism in mice using CRISPR/Cas9. Biochemical parameters in the Mthfr 677TT mice recapitulate alterations found in MTHFR 677TT men. Our aims were to characterize the sperm DNA methylome of the Mthfr 677CC and TT mice on a control diet (2 mg folic acid/kg diet) and assess the effects of folic acid supplementation (10 mg/kg diet) on the sperm DNA methylome. Body and reproductive organ weights, testicular sperm counts, and histology were examined. DNA methylation in sperm was assessed using bisulfite pyrosequencing and whole-genome bisulfite sequencing (WGBS). Reproductive parameters and locus-specific imprinted gene methylation were unaffected by genotype or diet. Using WGBS, sperm from 677TT mice had 360 differentially methylated tiles as compared to 677CC mice, predominantly hypomethylation (60% of tiles). Folic acid supplementation mostly caused hypermethylation in sperm of males of both genotypes and was found to partially correct the DNA methylation alterations in sperm associated with the TT genotype. The new mouse model will be useful in understanding the role of MTHFR deficiency in male fertility and in designing folate supplementation regimens for the clinic.

Folate Deficiency and/or the Genetic Variant Mthfr677C >T Can Drive Hepatic Fibrosis or Steatosis in Mice, in a Sex-Specific Manner

SCOPE

Disturbances in one-carbon metabolism contribute to nonalcoholic fatty liver disease (NAFLD) which encompasses steatosis, steatohepatitis, fibrosis, and cirrhosis. The goal is to examine impact of folate deficiency and the Mthfr677C >T variant on NAFLD.

METHODS AND RESULTS

This study uses the new Mthfr677C >T mouse model for the human MTHFR677C >T variant. Mthfr677CC and Mthfr677TT mice were fed control diet (CD) or folate-deficient (FD) diets for 4 months. FD and Mthfr677TT alter choline/methyl metabolites in liver and/or plasma (decreased S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio, methyltetrahydrofolate, and betaine; increased homocysteine [Hcy]). FD, with contribution from Mthfr677TT, provokes fibrosis in males. Studies of normal livers reveal alterations in plasma markers and gene expression that suggest an underlying predisposition to fibrosis induced by FD and/or Mthfr677TT in males. These changes are absent or reverse in females, consistent with the sex disparity of fibrosis. Sex-based differences in methylation potential, betaine, sphingomyelin, and trimethylamine-N-oxide (TMAO) levels may prevent fibrogenesis in females. In contrast, Mthfr677TT alters choline metabolism, dysregulates expression of lipid metabolism genes, and promotes steatosis in females.

CONCLUSION

This study suggests that folate deficiency predisposes males to fibrosis, which is exacerbated by Mthfr677TT, whereas Mthfr677TT predisposes females to steatosis, and reveal novel contributory mechanisms for these NAFLD-related disorders.

Leiomyoma and the importance of genetic variation on genes related to the vasculature system - CβS, MTHFR, NOS3, CYBA, and ACE1

OBJECTIVE

The link between the systemic vasculature system and tumor biology is here investigated by studying the contribution of CβS (844ins68), MTHFR (677C > T), NOS3 (4a/4b), CYBA (C242T), and ACE1 (I/D) genes to leiomyoma onset, uterus and leiomyoma volumes.

METHODS

DNA samples from 130 women with leiomyomas and 527 from healthy women were genotyped by PCR or PCR-RFLP. Qui-square (χ2) or Fisher's exact test were used to test associations. All the mentioned tests were performed in IBM® SPSS® Statistics Version 28. Statistical significance was defined as a p-value < 0.05.

RESULTS

Results revealed that CβS (in the codominant and allelic models, p = 0.044 and, p = 0.015, OR = 1.791 [1.114-2.879], respectively), MTHFR (in the codominant, allelic and dominant models, p = 0.009, p = 0.002, OR = 0.585 [0.416-0.824] and p = 0.003, OR = 0.527 [0.346-0.802], respectively) and ACE1 (dominant model, p = 0.045, OR = 0.639 [0.411-0.992]) genes are associated with leiomyoma onset. NOS3 4a4a genotype is associated with a lower uterus volume (p = 0.004). This study also uncovers intriguing epistatic interactions among some genes that further accentuate their roles in disease modulation. Indeed, the epistatic interactions between the CC genotype (MTHFR) and (+/+) (CβS; p = 0.003), 4b4b (NOS3; p = 0.006, OR = 2.050 [1.223-3.439]) or DD (ACE1; p < 0.001, OR = 2.362 [1.438-3.880]) were shown to be associated with the disease, while 4a presence (NOS3) in epistasis with I presence (ACE1), increased the effect protection having just the I allele presence (p = 0.029, OR = 0.446 [0.214-0.930]).

CONCLUSIONS

We conclude that variation in genes related to the systemic vascular system can play a role in the onset and development of leiomyoma.

Association Between Multiple Single Nucleotide Polymorphisms in Folate Metabolism Pathway and Breast Cancer Risk in Georgian Women: A Case-Control Study

Background

The folate metabolism pathway plays an integral part in DNA synthesis, methylation, and repair. Methylenetetrahydrofolate reductase (MTHFR) and methylenetetrahydrofolate dehydrogenase (MTHFD1) are both enzymes that are involved in this pathway, and the single nucleotide polymorphisms (SNPs) in genes coding for them have modulatory effects on DNA expression. This study aimed to investigate the relationship between MTHFR C677T (rs1801133) and MTHFD1 G1958A (rs2236225) polymorphisms and the risk of developing breast cancer in Georgian women.

Methods

A case-control study was performed examining the MTHFR C677T and MTHFD1 G1958A SNP in breast cancer-confirmed cases and healthy matched controls. Real time-polymerase chain reaction (PCR) was used to genotype SNPs. The case individuals' pathology reports were obtained following surgeries for cancer characteristic data. Statistical analysis was performed to investigate the significance of the acquired data.

Results

Statistical analysis of MTHFR C677T SNP revealed that the CT genotype increased the risk of breast cancer by 2.17 folds in the over-dominant model. Statistical analysis of MTHFD1 G1958A SNP showed that the GA genotype increased the risk of breast cancer by 4.12 folds in the codominant model and 2.41 folds in the over-dominant model. No statistically significant link was found between genotypes and lymph node status, however, patients with the CT genotype had higher percentages of proliferative activity.

Conclusions

Breast cancer seems to have a statistically significant association with the CT genotype in MTHFR C677T and the GA genotype in MTHFD1 G1958A in Georgian women.

Epigenetic Genome Modifications during Pregnancy: The Impact of Essential Nutritional Supplements on DNA Methylation

Pregnancy is an extremely stressful period in a pregnant woman's life. Currently, women's awareness of the proper course of pregnancy and its possible complications is constantly growing. Therefore, a significant percentage of women increasingly reach for various dietary supplements during gestation. Some of the most popular substances included in multi-ingredient supplements are folic acid and choline. Those substances are associated with positive effects on fetal intrauterine development and fewer possible pregnancy-associated complications. Recently, more and more attention has been paid to the impacts of specific environmental factors, such as diet, stress, physical activity, etc., on epigenetic modifications, understood as changes occurring in gene expression without the direct alteration of DNA sequences. Substances such as folic acid and choline may participate in epigenetic modifications by acting via a one-carbon cycle, leading to the methyl-group donor formation. Those nutrients may indirectly impact genome phenotype by influencing the process of DNA methylation. This review article presents the current state of knowledge on the use of folic acid and choline supplementation during pregnancy, taking into account their impacts on the maternal-fetal unit and possible pregnancy outcomes, and determining possible mechanisms of action, with particular emphasis on their possible impacts on epigenetic modifications.

Association of epistatic effects of MTHFR, ACE, APOB, and APOE gene polymorphisms with the risk of myocardial infarction and unstable angina in Egyptian patients

Despite remarkable discoveries in the genetic susceptibility of coronary artery disease (CAD), a large part of heritability awaits identification. Epistasis or gene-gene interaction has a profound influence on CAD and might contribute to its missed genetic variability; however, this impact was largely unexplored. Here, we appraised the associations of gene-gene interactions and haplotypes of five polymorphisms, namely methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE) insertion/deletion (I/D), apolipoprotein B (APOB) R3500Q, and apolipoprotein E (APOE) ε4 with the risk of myocardial infarction (MI) and unstable angina (UA). Gene-environment interactions with traditional risk factors and clinical data were also scrutinized. This study recruited 100 MI, 50 UA patients, and 100 apparently healthy controls. Logistic regression models were employed in association analyses. We remarked that the single locus effect of individual polymorphisms was relatively weak; however, a magnified effect of their combination via gene-gene interaction may predict MI risk after adjustment for multiple comparisons. Only MTHFR C677T, ACE I/D, and APOB R5300Q were associated with the risk of UA, and the ACE I/D-R3500Q interaction posed a decreased UA risk. APOB R3500Q was in strong linkage disequilibrium with MTHFR C677T, ACE I/D, and APE ε4 polymorphisms. The TCDGε3, CADGε4, and TADGε4-C677T-A1298C-ACE I/D-R3500Q-APOE haplotypes were associated with escalating MI risk, while the CDG or CIG-C677T-ACE I/D-R3500Q haplotype was highly protective against UA risk compared to controls. Interestingly, the CADGε4 and CAIGε3 haplotypes were strongly associated with the presence of diabetes and hypertension, respectively in MI patients; both haplotypes stratified patients according to the ECHO results. In UA, the CDG haplotype was negatively associated with the presence of diabetes or dilated heart. Conclusively, our results advocate that a stronger combined effect of polymorphisms in MTHFR, ACE, APOB, and APOE genes via gene-gene and gene-environment interactions might help in risk stratification of MI and UA patients.

Association between dietary folate intake and severe headache among adults in the USA: a cross-sectional survey

Folate, also known as vitamin B9, is a water-soluble vitamin. Previous studies on dietary folate intake in severe headache patients were equivocal. Therefore, we conducted a cross-sectional study to elucidate the relationship between folate intake and severe headache. This cross-sectional study used data from participants over 20 years old who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004. The diagnosis of severe headache was made through participants' self-report in the NHANES questionnaire section. We performed multivariate logistic regression and restricted cubic spline (RCS) regression to explore the relationship between folate intake and severe headache. A total of 9859 participants took part in the study, 1965 of whom were severe headache patients and the rest were non-severe headache. We found that dietary folate intake was significantly and inversely associated with severe headache. Compared with participants with lower folate intake Q1 (≤ 229·97 ug/d), the adjusted OR values for dietary folate intake and severe headache in Q2 (229·98-337 ug/d), Q3 (337·01-485 ug/d) and Q4 (≥ 485·01 ug/d) were 0·81 (95 % CI: 0·67, 0·98, P = 0·03), 0·93 (95 % CI: 0·77, 1·12, P = 0·41) and 0·63 (95 % CI: 0·49, 0·80, P < 0·001), respectively. For women aged 20-50 years, there was a non-linear association between folate intake and severe headache in the RCS. Women aged 20-50 years should have higher awareness of dietary folate and increase their dietary intake of folate, which may aid in preventing severe headache.

Clinical and laboratory findings and etiologies of genetic homocystinemia: a single-center experience

BACKGROUND

Homocysteine (Hcy) is an endogenous nonprotein sulfur-containing amino acid biosynthesized from methionine by the removal of its terminal methyl group. Hyperhomocysteinemia (HHcy) has been linked to many systemic disorders, including stroke, proteinuria, epilepsy, psychosis, diabetes, lung disease, and liver disease. The clinical effects of high serum Hcy level, also known as hyperhomocysteinemia, have been explained by different mechanisms. However, little has been reported on the clinical and laboratory findings and etiologies of genetic HHcy in children. This study aimed to examine the relationships between clinical features, laboratory findings, and genetic defects of HHcy.

METHODS

We retrospectively evaluated 20 consecutive children and adolescents with inherited HHcy at the pediatric neurology division of Baskent University, Adana Hospital (Adana, Turkey) between December 2011 and December 2022.

RESULTS

Our main finding is that the most common cause of genetic HHcy is MTHFR mutation. The other main finding is that the Hcy level was higher in patients with CBS deficiency and intracellular cbl defects than in MTHFR mutations. We also found that clinical presentations of genetic HHcy vary widely, and the most common clinical finding is seizures. Here, we report the first and only case of a cbl defect with nonepileptic myoclonus. We also observed that mild and intermediate HHcy associated with the MTHFR mutation may be related to migraine, vertigo, tension-type headache, and idiopathic intracranial hypertension. Although some of the patients were followed up in tertiary care centers for a long time, they were not diagnosed with HHcy. Therefore, we suggest evaluating Hcy levels in children with unexplained neurological symptoms.

CONCLUSIONS

Our findings suggest that genetic HHcy might be associated with different clinical manifestations and etiologies. Therefore, we suggest evaluating Hcy levels in children with unexplained neurologic symptoms.

Cardiogenic Shock in a Patient With 4G/4G PAI Polymorphism and MTHFR A1298C Mutation

Myocardial infarction (MI) remains a common cause of morbidity and mortality. Although many well-known risk factors exist, the association between inherited thrombophilia disorders and acute MI is not well described. Here, we present a case of a 75-year-old male with known 4G/4G PAI-1 polymorphism, methylenetetrahydrofolate reductase (MTHFR) mutation, and peripheral artery disease (PAD) post stent placement who presented with cardiogenic shock in the setting of acute MI with no prior significant cardiac history.

Current insights into genome-based personalized nutrition technology: a patent review

Unlike general nutritional ranges that meet the nutritional needs essential for maintaining the life of an entire population, personalized nutrition is characterised by maintaining health through providing customized nutrition according to individuals' lifestyles or genetic characteristics. The development of technology and services for personalized nutrition is increasing, owing to the acquisition of knowledge about the differences in nutritional requirements according to the diversity of individuals and an increase in health interest. Regarding genetics, technology is being developed to distinguish the various characteristics of individuals and provide customized nutrition. Therefore, to understand the current state of personalized nutrition technology, understanding genomics is necessary to acquire information on nutrition research based on genomics. We reviewed patents related to personalized nutrition-targeting genomics and examined their mechanisms of action. Using the patent database, we searched 694 patents on nutritional genomics and extracted 561 highly relevant valid data points. Furthermore, an in-depth review was conducted by selecting core patents related to genome-based personalized nutrition technology. A marked increase was observed in personalized nutrition technologies using methods such as genetic scoring and disease-specific dietary recommendations.

Association between COVID-19 Infection or Vaccination Outcomes and Methylenetetrahydrofolate Reductase Gene Polymorphism: A Systematic Review of the Literature

BACKGROUND

Thrombosis is a detrimental sequala of COVID-19 infection; thus, prophylactic anti-coagulant therapy has been deemed mandatory in treatment unless serious contraindications are present. Susceptibility to thromboembolic events in COVID-19, or following COVID-19 vaccination, is likely attributable to an interplay of factors, including a patient's baseline clinical status and comorbidities, alongside genetic risk factors. In Europe, 8-20% of the population are homozygous for the MTHFR (methylene tetrahydrofolate reductase) variant, which compromises folate metabolism and elevates homocysteine levels. While heightened homocysteine levels are considered a risk factor for thromboembolic events, the precise clinical significance remains a contentious issue. However, recent research suggests elevated homocysteine levels may predict the course and severity of COVID-19 infection. Given the lack of reliable biomarkers predictive of COVID-19 thrombotic risk existing in practice, and the accessibility of MTHFR screening, we established two main outcomes for this study: (1) to determine the association between hereditary MTHFR mutations and COVID-19 severity and thromboembolic events and (2) to determine the link between MTHFR variants and adverse thrombotic events following COVID-19 vaccination.

METHODS

The review was conducted in accordance with PRISMA guidelines. Medline, Scopus, and Web of Science databases were searched from pandemic inception (11 March 2020) to 30 October 2023. Eligibility criteria were applied, and data extraction performed.

RESULTS

From 63 citations identified, a total of 14 articles met the full inclusion criteria (8 of which were cross-sectional or observational studies, and 6 were case studies or reports). Among the eight observational and cross-sectional studies evaluating the relationship between MTHFR variants (C667T; A1298C) and thromboembolic events in COVID-19 infection, four studies established a connection (n = 2200), while the remaining four studies failed to demonstrate any significant association (n = 38).

CONCLUSIONS

This systematic review demonstrated a possible association between the MTHFR gene variants and COVID-19 severity, thromboembolic events, and adverse events following vaccination. However, the paucity of robust data precluded any firm conclusions being drawn. Further prospective trials are required to determine the connection between the MTHFR gene variant and COVID-19 infection and vaccination outcomes.

A bicarotid trunk with associated right retroesophageal subclavian artery in a child with neurofibromatosis type 1 complicated by a left hemispheric stroke

PURPOSE

To describe the association between two aortic arch branch variants and its possible relationship with neurofibromatosis-1.

METHODS

A 5-year-old female with NF-1 diagnosis presented to the emergency department at 2 months of age with irritability, vomiting and left gaze deviation. Brain MRI showed a left side acute hemispheric stroke and left internal carotid occlusion.

RESULTS

CT angiography of the neck showed the right and left common carotid arteries arising from a common vascular trunk coming from the aortic arch and a right retroesophageal subclavian artery.

CONCLUSION

Although the relationship between NF-1 mutation and aortic arch branch abnormalities has not been described, there is a recognized condition known as neurofibromatosis/Noonan syndrome which is an accepted variant of NF-1 with clinical features of both NF-1 and Noonan syndrome caused by dysregulation of the RAS-MAPK pathway. Aortic arch branch variations in patients with NF-1 could be explained by this association.

Susceptibility to preoperative seizures in glioma patients with elevated homocysteine levels

OBJECTIVE

Seizures are a common clinical presentation in patients with glioma and substantially impact patients' quality of life. Hyperhomocysteinemia is defined as abnormally high serum levels of homocysteine (Hcy) and is reportedly linked to susceptibility to various nervous system diseases. However, it remains unclear whether and how hyperhomocysteinemia and its associated genetic polymorphisms promote seizures in glioma patients.

METHODS

We retrospectively reviewed all medical data from 127 patients with malignant gliomas, who underwent initial tumor resection by our team between July 2019 and June 2021 and had preoperative measurements of serum Hcy levels. According to whether they had at least one seizure before surgery, they were divided into the seizure and nonseizure groups. We also detected polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and measured intratumoral Hcy levels in these patients.

RESULTS

Hyperhomocysteinemia was a susceptibility factor for preoperative seizures in glioma patients according to both univariate analyses (P < 0.001) and multivariate logistic regression analyses (OR 1.239, 95% CI 1.062-1.445, P = 0.007). Patients with the MTHFR C677T variant exhibited elevated serum Hcy levels (P = 0.027) and an increased prevalence of preoperative seizures (P = 0.019). Intratumoral Hcy levels were positively correlated with serum Hcy levels (R = 0.231, P = 0.046) and were elevated in patients with hyperhomocysteinemia (P = 0.031), the MTHFR C677T variant (P = 0.002) and preoperative seizures (P = 0.003). High intratumoral Hcy levels, rather than hyperhomocysteinemia or the MTHFR C677T variant, emerged as an independent risk factor for preoperative seizures (OR 1.303, 95% CI 1.015-1.673, P = 0.038). Furthermore, the effects of hyperhomocysteinemia on epileptic susceptibility were reduced to nonsignificance when intratumoral Hcy was controlled to the same level between groups.

SIGNIFICANCE

Glioma patients with hyperhomocysteinemia and the MTHFR C677T variant were susceptible to preoperative seizures, suggesting their potential as biomarkers for the management of seizures in glioma patients. The elevation of intratumoral Hcy is a possible mechanism underlying this susceptibility.

New insights into the nutritional genomics of adult-onset riboflavin-responsive diseases

Riboflavin, or vitamin B2, is an essential nutrient that serves as a precursor to flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). The binding of the FAD and/or FMN cofactors to flavoproteins is critical for regulating their assembly and activity. There are over 90 proteins in the human flavoproteome that regulate a diverse array of biochemical pathways including mitochondrial metabolism, riboflavin transport, ubiquinone and FAD synthesis, antioxidant signalling, one-carbon metabolism, nitric oxide signalling and peroxisome oxidative metabolism. The identification of patients with genetic variants in flavoprotein genes that lead to adult-onset pathologies remains a major diagnostic challenge. However, once identified, many patients with adult-onset inborn errors of metabolism demonstrate remarkable responses to riboflavin therapy. We review the structure:function relationships of mutant flavoproteins and propose new mechanistic insights into adult-onset riboflavin-responsive pathologies and metabolic dysregulations that apply to multiple biochemical pathways. We further address the vexing issue of how the inheritance of genetic variants in flavoprotein genes leads to an adult-onset disease with complex symptomologies and varying severities. We also propose a broad clinical framework that may not only improve the current diagnostic rates, but also facilitate a personalized approach to riboflavin therapy that is low cost, safe and lead to transformative outcomes in many patients.

Performance evaluation of QuantStudio 1 plus real-time PCR instrument for clinical laboratory analysis: A proof-of-concept study

Objective

The real-time PCR system is one of the most powerful research tools available in the life sciences field. The aim of this study was to preliminarily evaluate the analytical performance of QuantStudio 1 Plus real-time PCR system (QS 1 plus) for clinical procedures.

Methods

The consistency of QS 1 plus with the reference system in terms of various clinical procedures was evaluated. For qualitative data, the Kappa test was used to analyze the agreement of the results. For the quantitative data, Passing-Bablok regression analysis and Bland-Altman plot analysis were used to assess the concordance between QS 1 plus and the reference instrument.

Results

Passing-Bablok regression showed an excellent agreement between the QS 1 plus and LC 480 systems for HBV DNA quantification (y = 0.928 + 0.970x), whereas Bland-Altman plot analysis showed very small mean deviations between the two systems. The QS 1 plus yielded perfectly consistent results with the reference instrument for methylenetetrahydrofolate reductase (MTHFR) C677T melting curve genotyping analysis, MTHFR C677T genotyping analysis, Norovirus RNA negative/positive analysis, influenza B virus (Flu B) RNA negative/positive analysis, Mycobacterium tuberculosis (MTB) DNA negative/positive analysis, Human Papillomavirus (HPV) genotyping analysis, epidermal growth factor receptor (EGFR) gene mutation analysis. Both the relative quantitative analysis and the relative quantitative analysis (standard curve) confirmed the satisfactory concordance between the QS 1 plus instrument and the ABI 7500 instrument by Passing-Bablok regression analysis (y = 0.180 + 0.817x and y = 0.012 + 1.000x, respectively) and Bland-Altman plot analysis.

Conclusions

Our research has proven that QS 1 plus is adaptable to most test procedures in the clinical laboratory. This may provide the basis for its further application.

Challenges in treatment of gestational trophoblastic neoplasia in patients with MTHFR mutation: A case report

•We present a case of a patient with post molar pregnancy who has a MTHFR C677T mutation.•The mutation led to an alteration of recommended chemotherapy regimen.•No studies have reported treatment recommendations pertaining to gyn malignancies in patients with MTHFR allele.•We present a novel instance where MTHFR mutation altered a patient's treatment for gestational trophoblastic neoplasia.

Consistent Correlation between MTHFR and Vascular Thrombosis in Neonates-Case Series and Clinical Considerations

BACKGROUND

MTHFR polymorphism has been inconsistently linked to thrombotic events-some studies have shown its contribution to venous thrombosis, arterial thrombosis, and ischemic stroke, whereas others have found no statistically significant correlation between them.

METHODS

A descriptive case series study was performed in the Neonatal Intensive Care Unit of "Marie Sklodowska Curie" Emergency Clinical Hospital for Children in Bucharest, Romania.

RESULTS

All patients had positive results for MTHFR variants; 14 patients were positive for compound heterozygosity, 13 patients for MTHFR C677T (seven of which were homozygous), and 13 patients for MTHFR A1298C (three of which were homozygous). Eighteen patients received anticoagulants (heparin, enoxaparin, or bivalirudin), and thrombolytics (alteplase) were administered in six cases. In one case, a thrombectomy was performed; in another, vascular plasty was undertaken. Only in six cases was complete revascularization possible. Incomplete revascularization occurred for one patient with a negative outcome.

CONCLUSION

The particularity of this case series is that every patient in our unit who developed thrombi had a positive genetic result for MTHFR mutations. MTHFR mutations should be regarded as a thrombotic risk factor for critically ill patients, and screening for MTHFR mutations should be performed in every admitted patient to intensive care units, thus achieving the prevention of thrombi.

The STROMICS genome study: deep whole-genome sequencing and analysis of 10K Chinese patients with ischemic stroke reveal complex genetic and phenotypic interplay

Ischemic stroke is a leading cause of global mortality and long-term disability. However, there is a paucity of whole-genome sequencing studies on ischemic stroke, resulting in limited knowledge of the interplay between genomic and phenotypic variations among affected patients. Here, we outline the STROMICS design and present the first whole-genome analysis on ischemic stroke by deeply sequencing and analyzing 10,241 stroke patients from China. We identified 135.59 million variants, > 42% of which were novel. Notable disparities in allele frequency were observed between Chinese and other populations for 89 variants associated with stroke risk and 10 variants linked to response to stroke medications. We investigated the population structure of the participants, generating a map of genetic selection consisting of 31 adaptive signals. The adaption of the MTHFR rs1801133-G allele, which links to genetically evaluated VB9 (folate acid) in southern Chinese patients, suggests a gene-specific folate supplement strategy. Through genome-wide association analysis of 18 stroke-related traits, we discovered 10 novel genetic-phenotypic associations and extensive cross-trait pleiotropy at 6 lipid-trait loci of therapeutic relevance. Additionally, we found that the set of loss-of-function and cysteine-altering variants present in the causal gene NOTCH3 for the autosomal dominant stroke disorder CADASIL displayed a broad neuro-imaging spectrum. These findings deepen our understanding of the relationship between the population and individual genetic layout and clinical phenotype among stroke patients, and provide a foundation for future efforts to utilize human genetic knowledge to investigate mechanisms underlying ischemic stroke outcomes, discover novel therapeutic targets, and advance precision medicine.

Metabolic Analysis of Methylenetetrahydrofolate Reductase Single Nucleotide Polymorphisms (MTHFR 677C<T and MTHFR 1298A<C), Serum Folate and Vitamin B12 in Neural Tube Defects

Neural tube defects (NTDs) are among the most prevalent and debilitating birth defects with their causes are still unknown, despite mounting evidence that genetic and/or environmental factors may play a role. We aimed to analyze two single nucleotide polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene, serum folate and vitamin B12 status among a cohort of Egyptian children with NTDs and their mothers. A case-control study has been conducted on 50 Egyptian children with various types of NTDs and their mothers. They were comparable with 50 unrelated healthy, age and sex matched children and their mothers (50) selected as controls. Pediatric and neurosurgical assessments were performed to the included cases. Serum folate and vitamin B12 were measured using ELISA kits. MTHFR 677C Collapse

Key Words

• Folic acid
• Neural tube defects
• Vitamin B12
• rs1801131
• rs1801133

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Affiliation(s)

Mohammed H. Hassan Department of Medical Biochemistry, Faculty of Medicine, South Valley University, Qena, 83523 Egypt
Mohamed A. Raslan Department of Chemistry, Faculty of Science, Aswan University, Aswan, 81528 Egypt
Mena Tharwat Department of Chemistry, Faculty of Science, Aswan University, Aswan, 81528 Egypt
Hala M. Sakhr Department of Pediatrics, Faculty of Medicine, South Valley University, Qena, 83523 Egypt
Eslam El-Sayed El-Khateeb Department of Neurosurgery, Faculty of Medicine, South Valley University, Qena, 83523 Egypt
Shimaa Fathy Sakr Molecular Biology Unit, Medical Technology Center, Medical Research Institute, Alexandria University, Alexandria, Egypt
Hesham H. Ameen Department of Clinical Pathology, Faculty of Medicine, Al-Azhar University (Assiut Branch), Assiut, Egypt
Ali R. Hamdan Department of Neurosurgery, Faculty of Medicine, South Valley University, Qena, 83523 Egypt

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Hyperhomocysteinemia and Accelerated Aging: The Pathogenic Role of Increased Homocysteine in Atherosclerosis, Osteoporosis, and Neurodegeneration

Cardiovascular diseases and osteoporosis, seemingly unrelated disorders that occur with advanced age, share major pathogenetic mechanisms contributing to accelerated atherosclerosis and bone loss. Hyperhomocysteinemia (hHcy) is among these mechanisms that can cause both vascular and bone disease. In its more severe form, hHcy can present early in life as homocystinuria, an inborn error of metabolic pathways of the sulfur-containing amino acid methionine. In its milder forms, hHcy may go undiagnosed and untreated into adulthood. As such, hHcy may serve as a potential therapeutic target for cardiovascular disease, osteoporosis, thrombophilia, and neurodegeneration, collectively representing accelerated aging. Multiple trials to lower cardiovascular risk and improve bone density with homocysteine-lowering agents, yet none has proven to be clinically meaningful. To understand this unmet clinical need, this review will provide mechanistic insight into the pathogenesis of vascular and bone disease in hHcy, using homocystinuria as a model for accelerated atherosclerosis and bone density loss, a model for accelerated aging.

Primary Intracranial Ewing Sarcoma Invading the Superior Sagittal Sinus with EWSR1-FLI1 Gene Fusion and EWSR1 Gene Mutation: A Case Report and Literature Review

BACKGROUND

Primary intracranial Ewing sarcoma (ES) is an extremely rare intracranial malignant tumor, mostly occurring in children and adolescents. Because of its rarity, the magnetic resonance imaging (MRI) features and treatment strategies of primary intracranial ES are still unclear.

METHODS

The purpose of this study was therefore to report a case of primary intracranial ES, whose molecular features included both EWSR1-FLI1 (EWS RNA binding protein 1- Friend leukemia integration 1) gene fusion and EWSR1 gene mutation. It is worth noting that this is the first reported case of ES invading the superior sagittal sinus and mostly causing occlusion. At the same time, there were polymorphisms of four drug metabolism-related enzymes in the tumor. Subsequently, we conducted a literature review to characterize the clinical features, imaging findings, pathological features, treatments, and prognoses of primary intracranial ESs.

RESULTS

A 21-year-old female was admitted to the hospital with headache with nausea and vomiting for 2 weeks. An MRI showed a 3.8 × 4.0 cm large heterogeneous mass in the bilateral parietal lobe with peritumoral edema. The tumor invaded the superior sagittal sinus and mostly caused occlusion of the middle segment of the superior sagittal sinus. The mass was successfully removed using a neuromicroscope. Postoperative pathology indicated a primary intracranial ES. High throughput sequencing (next generation sequencing) showed that there was EWSR1-FLI1 gene fusion and EWSR1 gene mutation in the tumor, with polymorphisms of four drug metabolism-related enzymes and low tumor mutational burden. Subsequently, the patient received intensity modulated radiation therapy. The patient has signed an informed consent form.

CONCLUSIONS

The diagnosis of primary intracranial ES depended on histopathology, immunohistochemistry staining, and genetic testing. At present, total tumor resection combined with radiotherapy and chemotherapy is the most effective treatment. We report the first case of primary intracranial ES invading the superior sagittal sinus and causing middle segment occlusion, accompanied by EWSR1-FLI1 gene fusion and EWSR1 gene mutation.

MTHFR act as a potential cancer biomarker in immune checkpoints blockades, heterogeneity, tumor microenvironment and immune infiltration

PURPOSE

To evaluate the role and landscape of 5-10-Methylenetetrahydrofolate reductase (MTHFR) to immune infiltration, tumor microenvironment, heterogeneity, immune checkpoints blockades, prognostic significance across cancer types.

METHODS

Data sets of genomic, transcriptomic and clinic features of MTHFR across > 60,000 patients and up to 44 cancer types were comprehensively analyzed using R software.

RESULTS

Expression of MTHFR gene is significantly lower in 17 tumors and correlated with overall survival (OS), disease-specific survival (DSS), progression-free interval (PFI) in specific tumors. Gene alterations of MTHFR are observed significant differences across tumor types. Expression of MTHFR is negatively correlated with the stemness index (mDNAsi, mRNAsi, DMPsi, ENHsi, EREG-mDNAsi and EREG-mRNAsi) in the most cancers. MTHFR showed significantly correlated with 67 types of immune cell infiltration scores in 44 cancer types by XCELL algorithm. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis are conducted to show the core tumor mechanism and biological process. Correlations between MTHFR and biomarkers of heterogeneity (MSI, TMB, MATH, HRD, LOH, Neoantigen, ploidy and purity) are also significant in specific tumors. MTHFR is significantly positively correlated with biomarkers of immune related genes (CD19, CD274, CD80, CD86) and mismatched repair genes (MLH1, PMS2, MSH2, MSH6, EPCAM, MLH3, PMS1, EXO1) in most cancer types. Receiver Operating Characteristics (ROC) analyses show MTHFR could act as a potential biomarker in anti-PD-1 (nivolumab to melanoma) and anti-CTLA4 (ipilimumab to melanoma) group of ontreatment, in anti-PD-1 (pembrolizumab to melanoma) group of pretreatment. Two immunohistochemistry antibodies HPA076180 and HPA077255 are verified in 20 types of tumor and could be used to detect the expression of MTHFR efficiently in clinic.

CONCLUSIONS

MTHFR could predict the response of immune checkpoints blockades, heterogeneity, tumor microenvironment and immune infiltration.

Effects of folic acid supplementation on chronic atrophic gastritis based on MTHFR C677T polymorphism

BACKGROUND

It has been shown the methylenetetrahydrofolate reductase (MTHFR) 677TT (rs 1801133) genotype predicts histopathological alterations in the incisura of patients with chronic atrophic gastritis (CAG). MTHFR is a crucial enzyme in fatty acid (FA) metabolism. This study aimed to evaluate the influence of FA supplementation in CAG patients without Helicobacter pylori infection and the MTHFR C677T (rs 1801133) genotype as a potential CAG predictor.

METHODS

A total of 96 CAG patients, aged 21 to 72 years old, were enrolled in this study. After 6 months of treatment, histopathological outcomes were compared among patients treated with weifuchun (WFC) (1.44 g 3 times per os per day), those treated with WFC and FA (5 mg once daily), and those treated with WFC, FA, and vitamin B12 (VB12) (0.5 mg 3 times per day) based on the Operative Link on Gastritis/Intestinal Metaplasia assessment staging systems.

RESULTS

Atrophic lesions in patients treated with WFC and FA improved more than in patients treated only with WFC therapy (78.1% vs 53.3%, P = .04). Atrophic or intestinal metaplasia (IM) lesions in the incisura of patients with the TT genotype were better than those in patients with the CC/CT genotype (P = .02).

CONCLUSION

The treatment of CAG patients with 5 mg of FA supplements daily for 6 months improved their gastric atrophy status, especially for the Operative Link on Gastritis/Intestinal Metaplasia assessment stages I/II. Moreover, our study is the first to reveal that patients with the MTHFR 677TT genotype require more timely and effective FA treatment than those with the CC/CT genotype.

Recurrent Pregnancy Loss Etiology, Risk Factors, Diagnosis, and Management. Fresh Look into a Full Box

Recurrent pregnancy loss is a complex health challenge with no universally accepted definition. Inconsistency in definitions involves not only the number of spontaneous abortions (two or three) that are accepted for recurrent pregnancy loss but the types of pregnancy and gestational age at miscarriage. Due to the heterogeneity of definitions and criteria applied by international guidelines for recurrent pregnancy loss, the true incidence of recurrent miscarriage, which is reported to range from 1% to 5%, is difficult to estimate. Moreover, the exact etiology of recurrent pregnancy loss remains questionable; thus, it is considered a polyetiological and multifactorial condition with many modifiable and non-modifiable factors involved. Even after thoroughly evaluating recurrent pregnancy loss etiology and risk factors, up to 75% of cases remain unexplained. This review aimed to summarize and critically analyze accumulated knowledge on the etiology, risk factors, relevant diagnostic options, and management approach to recurrent pregnancy loss. The relevance of various factors and their proposed roles in recurrent pregnancy loss pathogenesis remains a matter of discussion. The diagnostic approach and the management largely depend on the etiology and risk factors taken into consideration by a healthcare professional as a cause of recurrent miscarriage for a particular woman or couple. Underestimation of social and health consequences of recurrent pregnancy loss leads to compromised reproductive health and psychological well-being of women after miscarriage. Studies on etiology and risk factors for recurrent pregnancy loss, especially idiopathic, should be continued. The existing international guidelines require updates to assist clinical practice.

Case report: Young-onset large vessel ischemic stroke due to hyperhomocysteinemia associated with the C677T polymorphism on 5,10-methylenetetrahydrofolate reductase and multi-vitamin deficiency

Hyperhomocysteinemia is an important risk factor for cerebral infarction. Herein, we report on a 30-year-old man previously diagnosed with epilepsy who presented with right hemiplegia and total aphasia. Magnetic resonance imaging showed a fronto-temporal ischemic lesion due to occlusion of the left middle cerebral artery. Clinical testing and imaging demonstrated that he had hyperhomocysteinemia induced by multiple factors including the C677T polymorphism on 5.10-methylenetetrahydrofolate reductase (MTHFR), and multiple vitamin deficiencies. The C677T polymorphism on MTHFR is closely related to hyperhomocysteinemia and folate deficiency in epileptic patients who are taking multiple anti-convulsants. Given hyperhomocysteinemia can independently cause stroke at a young age, physicians should periodically examine plasma homocysteine and serum folic acid levels in epileptic patients who are on long-term regimens of multiple anti-epileptic drugs.

The association between serum folate and gestational diabetes mellitus: a large retrospective cohort study in Chinese population

OBJECTIVE

To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.

DESIGN

In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage-response relationship between serum folate and the risk of GDM.

SETTING

A sigle, urban hospital in Shanghai, China.

PARTICIPANTS

A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.

RESULTS

Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs).

CONCLUSIONS

The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.

Maternal pre-pregnancy BMI, MTHFR polymorphisms, and the risk of adverse pregnancy outcomes in pregnant women from South China: a retrospective cohort study

BACKGROUND

Increasing evidence suggests an association between maternal pre-pregnancy body mass index (pre-BMI) and adverse pregnancy outcomes. However, the effects of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on these relationships require further investigation. This study aimed to investigate whether the relationship between pre-BMI and the risk of adverse pregnancy outcomes was influenced by MTHFR gene polymorphisms.

METHODS

A total of 5614 mother-fetus pairs were included in the study. The odds ratios (OR) of adverse pregnancy complications, including gestational diabetes mellitus (GDM), gestational hypertension (GHT), cesarean delivery (CS), and premature rupture of membranes (PROM), were estimated using adjusted logistic regression models and subgroup analysis.

RESULTS

Pregnant women with higher pre-BMI values were positively related to the risk of GDM, GHT, and CS. In the subgroup analysis, underweight BMI was associated with a decreased risk of CS and GDM in pregnant women with the MTHFR A1298C AA or C677T CC genotype, while overweight/obese BMI was associated with an increased risk of GDM and CS in different MTHFR variants. Moreover, pregnant women with MTHFR A1298C AC + CC or C667T CC were found to have an increased risk of GHT in the MTHFR A1298C AA or C667T CT + TT genotype. A remarkable association was observed between the obesity group with MTHFR A1298C AC + CC (OR = 6.49, CI: 2.67-15.79) and the overweight group with the C667T CC genotype (OR = 4.72, CI: 2.13-10.45).

CONCLUSIONS

MTHFR gene polymorphisms exert a modifying effect on the association between maternal pre-BMI and the risk of GHT, CS, and GDM. Pregnant women with a high pre-BMI with specific MTHFR genotypes should be considered for GHT development.

Effects of Folic Acid Supplementation on Liver Enzymes, Lipid Profile, and Insulin Resistance in Patients with Non-Alcoholic Fatty Liver Disease: A Randomized Controlled Trial

Background

Previous evidence revealed an association between folate deficiency and non-alcoholic fatty liver disease (NAFLD). This study is the first one investigating the effects of folic acid on hepatic steatosis grade, liver enzymes, insulin resistance, and lipid profile in NAFLD cases.

Materials and Methods

Sixty-six participants with NAFLD were allocated randomly to take either a placebo or one oral tablet of folic acid (1 mg) on a daily basis within eight weeks. Serum folate, homocysteine, glucose, aminotransferases, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and lipids were assessed. Ultrasonography was used for assessing the liver steatosis grade.

Results

The serum alanine transaminase, grade of hepatic steatosis, and aspartate transaminase significantly were decreased within both study groups; however, the between-group comparison was not statistically significant. Of note, the decrease in ALT was more pronounced in folic acid compared with the placebo group (-5.45 ± 7.45 vs. -2.19 ± 8.6 IU/L). The serum homocysteine was decreased after receiving folic acid compared to the placebo (-0.58 ± 3.41 vs. +0.4 ± 3.56 μmol/L; adjusted P = 0.054). Other outcomes did not significantly change.

Conclusion

Supplementation with folic acid (1 mg/d) for eight weeks among cases with NAFLD did not change significantly the serum levels of liver enzymes, the hepatic steatosis grade, insulin resistance and lipid profile. However, it was able to prevent the increase in homocysteine in comparison with the placebo. Conducting further research is suggested with the longer duration and different doses of folic acid, adjusted to the genotypes of methylenetetrahydrofolate reductase polymorphism, among NAFLD patients.

Association between Micronutrients and Hyperhomocysteinemia: A Case-Control Study in Northeast China

Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular and cerebrovascular diseases where the plasma homocysteine (Hcy) concentration exceeds 15 µmol/L. HHcy is affected by vitamins B12, B6, and folic acid (fol); however, its relationship with other nutrients is not fully understood. We investigated the nutritional and genetic factors associated with HHcy and the possible dose-response relationships or threshold effects in patients in Northeast China. Genetic polymorphisms and micronutrients were tested with polymerase chain reaction and mass spectrometry, respectively. This trial was registered under trial number ChiCTR1900025136. The HHcy group had significantly more males and higher body mass index (BMI), methylenetetrahydrofolate reductase (MTHFR 677TT) polymorphism proportion, and uric acid, Zn, Fe, P, and vitamin A levels than the control group. After adjusting for age, sex, BMI, vitamin B12, fol, and MTHFR C677T, the lowest Zn quartile reduced the odds ratio of HHcy compared with the highest Zn quartile. The dose-response curves for the association between plasma Zn and HHcy were S-shaped. High plasma Zn concentrations were significantly correlated with high HHcy odds ratios, and the curve leveled off or slightly decreased. Most importantly, HHcy risk decreased with decreasing plasma Zn concentration; the threshold was 83.89 µmol/L. Conclusively, individuals residing in Northeast China, especially those with the MTHFR 677TT polymorphism, must pay attention to their plasma Zn and Hcy levels.

Genome-wide Association Study of Methotrexate-Induced Liver Injury in Rheumatoid Arthritis Patients

Hepatotoxicity is a serious adverse drug reaction related to methotrexate (MTX). However, the cause of drug-induced liver injury (DILI) is still unclear and unpredictable. Genetic risk factors may predispose for MTX-DILI. Therefore, we conducted a nested case-control genome-wide association study to explore genetic risk factors associated with MTX-DILI. Seven international groups contributed blood samples and data of patients with rheumatoid arthritis who used MTX. MTX-DILI was defined as an alanine aminotransferase (ALT) level of at least three times the upper limit of normal (ULN), to increase contrast controls ALT levels did not raise above two times the ULN. Per study site, control subjects and patients with MTX-DILI (ratio 3:1) were matched for age, gender, and duration of MTX use. Patients were genotyped using Illumina GSA MD-24v1-0 and data were imputed using the 1000 Genomes reference panel. Single-nucleotide polymorphisms (SNPs) were analyzed using an additive genetic model, corrected for sex, country, and age. A P-value of ≤ 5 × 10^-8 was considered significant, whereas a  P-value of ≤ 5 × 10^-6 was considered suggestive. A total of 108 MTX-DILI cases and 311 controls were included for association analysis. None of the SNPs were significantly associated with MTX-DILI. However, we found seven suggestive genetic variants associated with MTX-DILI (P-values 7.43 × 10^-8 to 4.86 × 10^-6 ). Of those, five SNPs were in the intronic protein-coding regions of FTCDNL1, BCOR, FGF14, RBMS3, and PFDN4/DOK5. Investigation of candidates SPATA9 (rs72783407), PLCG2 (rs60427389), RAVER2 (rs72675408), JAK1 (rs72675451), PTPN2 (rs2476601), MTHFR C677T (rs1801133), and into the HLA region did not show significant findings. No genetic variants associated with MTX-DILI were found, whereas suggestive SNPs need further investigation.

Thrombophilia and Immune-Related Genetic Markers in Long COVID

Aiming to evaluate the role of ten functional polymorphisms in long COVID, involved in major inflammatory, immune response and thrombophilia pathways, a cross-sectional sample composed of 199 long COVID (LC) patients and a cohort composed of 79 COVID-19 patients whose follow-up by over six months did not reveal any evidence of long COVID (NLC) were investigated to detect genetic susceptibility to long COVID. Ten functional polymorphisms located in thrombophilia-related and immune response genes were genotyped by real time PCR. In terms of clinical outcomes, LC patients presented higher prevalence of heart disease as preexistent comorbidity. In general, the proportions of symptoms in acute phase of the disease were higher among LC patients. The genotype AA of the interferon gamma (IFNG) gene was observed in higher frequency among LC patients (60%; p = 0.033). Moreover, the genotype CC of the methylenetetrahydrofolate reductase (MTHFR) gene was also more frequent among LC patients (49%; p = 0.045). Additionally, the frequencies of LC symptoms were higher among carriers of IFNG genotypes AA than among non-AA genotypes (Z = 5.08; p < 0.0001). Two polymorphisms were associated with LC in both inflammatory and thrombophilia pathways, thus reinforcing their role in LC. The higher frequencies of acute phase symptoms among LC and higher frequency of underlying comorbidities might suggest that acute disease severity and the triggering of preexisting condition may play a role in LC development.

Biological Role of Folic Acid in Pregnancy and Possible Therapeutic Application for the Prevention of Preeclampsia

The rationale and importance of folic acid supplementation during pregnancy for fetal congenital defect prevention are accepted worldwide. Moreover, a sufficient plasma concentration of folates can reduce the incidence of spontaneous abortions, and support the normal expansion of placental blood vessels, ensuring physiological placental blood flow, thus promoting appropriate fetal growth and development. Furthermore, there is emerging evidence that long-term supplementation with folic acid can effectively prevent preeclampsia. Preeclampsia is unique to the human species in complications during pregnancy, which contributes to maternal and perinatal mortality worldwide. In the pathogenesis of preeclampsia abnormal placental invasion, the excess of antiangiogenic factors and maternal-placental syndrome play a key role. Increased blood levels of homocysteine during pregnancy are associated with the risk of preeclampsia. Moreover, hyperhomocysteinemia has been proposed to be an independent risk factor for preeclampsia. Folate supplementation helps to decrease elevated levels of homocysteine; thus, the role of folic acid supplementation in pregnancy is even more important. Multiple reports suggest that folate administration decreases the level of serum homocysteine and, therefore, reduce the risk and severity of preeclampsia. However, the association between folic acid supplementation and the decreased risk of preeclampsia has been investigated with controversial conclusions. Currently, the optimal dose of folic acid that is effective for preeclampsia prevention remains uncertain. In this review, we aim to summarize the accumulated knowledge on the role of folic acid in the pathogenesis of preeclampsia, and the possible impact of folate supplementation on the decreased risk of preeclampsia.

Lack of Association of C677T Methylenetetrahydrofolate Reductase Polymorphism with Breast Cancer Risk in Mali

Methylenetetrahydrofolate reductase (MTHFR) plays a major role in the metabolism of folates and homocysteine, which in turn can affect gene expression and ultimately promote the development of breast cancer. Thus, mutations in the MTHFR gene could influence homocysteine, methionine, and S-adenosylmethionine levels and, indirectly, nucleotide levels. Imbalance in methionine and S-adenosylmethionine synthesis affects protein synthesis and methylation. These changes, which affect gene expression, may ultimately promote the development of breast cancer. We therefore hypothesized that such mutations could also play an important role in the occurrence and pathogenesis of breast cancer in a Malian population. In this study, we used the PCR-RFLP technique to identify the different genotypic profiles of the C677T MTHFR polymorphism in 127 breast cancer women and 160 healthy controls. The genotypic distribution of the C677T polymorphism in breast cancer cases was 88.2% for CC, 11.0% for CT, and 0.8% for TT. Healthy controls showed a similar distribution with 90.6% for CC, 8.8% for CT, and 0.6% for TT. We found no statistical association between the C677T polymorphism and breast cancer risk for the codominant models CT and TT (p > 0.05). The same trend was observed when the analysis was extended to other genetic models, including dominant (p = 0.50), recessive (p = 0.87), and additive (p = 0.50) models. The C677T polymorphism of MTHFR gene did not influence the risk of breast cancer in the Malian samples.

Association of methylenetetrahydrofolate reductase (MTHFR) rs1801133 (677C>T) gene polymorphism with ischemic stroke risk in different populations: An updated meta-analysis

Background: Recently, increasing evidence has implicated methylenetetrahydrofolate reductase (MTHFR) gene mutation as a risk factor for ischemic stroke (IS) in the general population. However, studies have been inconclusive and lack evidence on specific populations. We aim to determine whether the rs1801133 (NC_000001.11 (MTHFR):g. 677C>T (p.Ala222Val) variant, we termed as MTHFR rs1801133 (677 C>T), is linked to an increased risk of IS in different age groups and ancestry groups. Methods: The literature relevant to our study was found by searching the PubMed, Cochrane Library, Web of Science, EMBASE, and CNKI databases. A random effect model analysis was used to calculate the pooled odds ratio (OR) and 95% confidence interval (CI) to evaluate any possible association. We conducted a subgroup analysis based on the age and ancestry groups of the included populations. Results: As of March 2022, 1,925 citations had been identified in electronic databases, of which 96 studies involving 34,814 subjects met our eligibility criteria. A strong link was found between IS and the MTHFR gene rs1801133 (677C>T) polymorphism in all genetic models [dominant genetic model (OR = 1.47; 95%CI = 1.33-1.61; p < 0.001), recessive genetic model (OR = 1.52; 95%CI = 1.36-1.71; p < 0.001), heterozygous model (OR = 1.36; 95%CI = 1.24-1.48; p < 0.001), homozygous model (OR = 1.82; 95%CI = 1.58-2.11; p < 0.001), and T allelic genetic model (OR = 1.37; 95%CI = 1.27-1.48; p < 0.001)]. Further subgroup analyses indicated that the MTHFR rs1801133 (677C>T) variant may increase the risk of IS in Asian, Hispanic, or Latin population, middle-aged, and elderly populations (p < 0.001). Conclusion: Our results implied that mutation of the T allele of MTHFR rs1801133 (677C>T) could be a risk factor for IS. A significant association was found among Asian, Hispanic, or Latin population, middle-aged, and elderly people.

Homocysteine, Vitamin B12 and Folate Level: Possible Risk Factors in the Progression of Chronic Heart and Kidney Disorders

Cobalamin is an essential molecule for humans; it is exceptionally important for various body functions, including deoxyribonucleic acid synthesis and cellular energy production. Vegans are more vulnerable to vitamin B12 deficiency than natives with moderate consumption of animal dietary supplements or people with inadequate nutritional patterns. However, the long-term effects of sub-medical deficiency have not been thoroughly studied, but they may have a negative impact on the cardiovascular system, pregnancy outcomes, and vascular, renal, cognitive, bone, and eye health. Alongside the statin remedy, that is a powerful approach for CVD prevention. Another approach is related to the B nutrition substitution remedy with folic acid, and vitamins B6 and B12 are extensively practised nowadays. There is a tremendous interest in plasma homocysteine (tHcy) as a cardiovascular hazard factor. However, current research in the field of its prevention is more inclined toward confirming the benefit of tHcy-reducing remedy with vitamin B12. Thus, while folic acid fortification is primarily aimed at reducing neural-tube defects, it may also play a significant role in the primary prevention of CVD by lowering tHcy. Folate and B-vitamins play important roles in CVD prevention and nutrition policy implementation. Patients affected with Chronic Kidney Disease (CKD) or end-stage Stage Renal Disease (ESRD) experience a tremendous cardiovascular threat that may also further lead to death. As a result, routine monitoring of vitamin B12 levels is likely to be beneficial for the early detection and treatment of metabolic vitamin B12 deficiency, as well as the prevention of heart-related diseases.

Methylenetetrahydrofolate Reductase 677T Allele Is a Risk Factor for Arterial Thrombosis in Chinese Han Patients with Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by the persistent presence of antiphospholipid antibodies (aPL) and thrombotic or obstetric events. Given the heterogeneity of the clinical manifestations, it is likely that genetic and acquired factors are involved in the pathogenesis of APS. The inherited polymorphisms of the thrombophilic gene, including methylenetetrahydrofolate reductase (MTHFR) C677T, type 1 plasminogen activator inhibitor (PAI-1) 4G/5G, factor V Leiden (FVL) G1691A, prothrombin (PT) G20210A, antithrombin (AT), and fibrinogen (Fg) polymorphisms, were analyzed in 67 aPL(+) patients from the Chinese Han population, including 41 APS patients and 26 persistent aPL carriers. The MTHFR C677T genotypes of 105 healthy controls, and the PAI-1 4G/5G polymorphism of 120 healthy controls, from the Chinese Han population were acquired for this study. Both the MTHFR C677T genotype (χ² = 10.67, p = 0.004) and C/T allele distribution (χ² = 5.92, p = 0.019) between the aPL(+) patients and healthy controls were found to be significantly different. Furthermore, we observed that the patients with at least one T allele had a higher risk of arterial thrombosis (CT vs. CC, OR 11.00, p= 0.025; CT + TT vs. CC, OR 10.27, p = 0.018). The C677T mutation of MTHFR is a risk factor for arterial thrombosis in Chinese Han patients with APS.

Clinical and genetic aspects of menopausal hormone therapy - a modern paradigm. What changed COVID-19 pandemic?

In the modern paradigm of public health protection, much attention is paid to the health of women in peri- and postmenopause, and a personalized approach prevails. It is generally recognized that the pathogenetic therapy of menopausal disorders is hormone therapy. But the COVID-19 pandemic has made its own adjustments to the routine strategy of choosing menopausal hormone therapy (MHT). The purpose of this review was to analyze studies on the dependence of the effectiveness of MHT on clinical and genetic aspects in the context of the ongoing COVID-19 pandemic. The review highlights the main risks of MHT for thromboembolic diseases and coagulation complications characteristic of COVID-19, discusses genetic predispositions that aggravate the course of the post-COVID period, as well as the effectiveness of estrogens in protecting the vascular endothelium and increasing the number of CD4+ T cells, providing an adequate immune response when infected with SARS-CoV-2. Numerous studies show that the complications characteristic of the severe course of COVID-19 are multifactorial in nature and cannot be unambiguously explained only by genetic predisposition. However, with the development of personalized medicine, special attention should be paid to the study of genetic aspects that can equally contribute to the occurrence of menopausal disorders in healthy women and aggravate the course of the post-pregnancy period. The data presented allow us to conclude that in the context of the ongoing COVID-19 pandemic at the population level, MHT can bring significant benefits to women during menopause due to the beneficial effect of estrogens on vascular walls. Additional study of the relationship between the course of the postcovid period in MHT users and polymorphisms of candidate genes that determine the risks of thrombotic complications and metabolic consequences is required.

Olive Oil in the Mediterranean Diet and Its Biochemical and Molecular Effects on Cardiovascular Health through an Analysis of Genetics and Epigenetics

Human nutrition is a relatively new science based on biochemistry and the effects of food constituents. Ancient medicine considered many foods as remedies for physical performance or the treatment of diseases and, since ancient times, especially Greek, Asian and pre-Christian cultures similarly thought that they had beneficial effects on health, while others believed some foods were capable of causing illness. Hippocrates described the food as a form of medicine and stated that a balanced diet could help individuals stay healthy. Understanding molecular nutrition, the interaction between nutrients and DNA, and obtaining specific biomarkers could help formulate a diet in which food is not only a food but also a drug. Therefore, this study aims to analyze the role of the Mediterranean diet and olive oil on cardiovascular risk and to identify their influence from the genetic and epigenetic point of view to understand their possible protective effects.

Mild methylenetetrahydrofolate reductase deficiency accelerates liver triacylglycerol and uric acid accumulation in fructose-fed mice

A genetic predisposition to hepatic steatosis may be associated with dietary patterns. We hypothesized that a common variant in human methylenetetrahydrofolate reductase (MTHFR 677C→T) was previously associated with an increased risk of nonalcoholic fatty liver disease (NAFLD). In this study, we investigated the relationship between the human MTHFR polymorphism and NAFLD using fructose-fed male C57BL/6 Mthfr^+/+ and Mthfr^+/- mice, a model for the human gene variant. Mice were fed an 8% fructose solution for 12 weeks. Mthfr^+/- mice had significantly increased abdominal fat mass and hepatic triglyceride (TG) but displayed a similar liver mass when compared with Mthfr^+/+ mice. Liver morphology showed that mild MTHFR deficiency induced liver lipid droplet deposition and inflammatory cell infiltration, suggesting accelerated lipid accumulation in the liver. Moreover, mild MTHFR deficiency increased hepatic xanthine oxidase activity and uric acid accumulation. Using untargeted lipidomics, we identified 116 differentially expressed lipids species in the liver of Mthfr^+/- mice when compared with Mthfr^+/+ animals. The most significant lipid increase was observed in 47 TGs, followed by 33 phosphatidylcholines in Mthfr^+/- mice liver. When compared with Mthfr^+/+ liver, 9 TGs were dramatically decreased in Mthfr^+/- liver. These changes were associated with upregulated gene expressions related to triglyceride synthesis and storage. Thus, Mthfr^+/- mice developed NAFLD disease. These findings suggested the Mthfr variant may be at an increased risk of liver steatosis on a fructose solution diet.