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

Genetic polymorphisms in folate metabolism and their association with recurrent spontaneous abortion

OBJECTIVE

This study aims to investigate the relationship between polymorphisms in key enzyme genes involved in folate metabolism and recurrent spontaneous abortion (RSA).

METHODS

Genotypic data and red blood cell folate levels were collected from 150 patients with RSA and 120 healthy controls. The genotype and allele frequency distribution at the methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C, and methionine synthase reductase (MTRR) A66G loci were analyzed and compared. Additionally, homocysteine levels were measured.

RESULTS

Significant differences in genotype and allele frequencies were observed between the RSA group and the control group at the MTHFR C677T and MTRR A66G loci. Specifically, the distribution of genotypes and alleles at the MTHFR C677T locus showed a marked divergence between the two groups. In the RSA group, the frequency of the TT genotype was notably higher compared to the control group, suggesting a potential association with an increased risk of recurrent spontaneous abortion. Similarly, at the MTRR A66G locus, the AG and GG genotypes were more prevalent in the RSA group than in the control group, further implicating these genetic variants in the pathogenesis of RSA.

CONCLUSION

We identified a significant association between the TT genotype of MTHFR C677T and reduced red blood cell folate concentration. Additionally, the AG and GG genotypes of MTRR A66G were found to be linked to an increased risk of RSA. These findings suggest that specific variants in genes encoding folate metabolism enzymes may contribute to the risk of recurrent spontaneous abortion.

Widespread recessive effects on common diseases in a cohort of 44,000 British Pakistanis and Bangladeshis with high autozygosity

Genetic association studies have focused on testing additive models in cohorts with European ancestry. Little is known about recessive effects on common diseases, specifically for non-European ancestry. Genes & Health is a cohort of British Pakistani and Bangladeshi individuals with elevated rates of consanguinity and endogamy, making it suitable to study recessive effects. We imputed variants into a genotyped dataset (n = 44,190) by using two reference panels: a set of 4,982 whole-exome sequences from within the cohort and the Trans-Omics for Precision Medicine (TOPMed-r2) panel. We performed association testing with 898 diseases from electronic health records. 185 independent loci reached genome-wide significance (p < 5 × 10-8) under the recessive model, with p values lower than under the additive model, and >40% of these were novel. 140 loci demonstrated nominally significant (p < 0.05) dominance deviation p values, confirming a recessive association pattern. Sixteen loci in three clusters were significant at a Bonferroni threshold, accounting for multiple phenotypes tested (p < 5.4 × 10-12). In FinnGen, we replicated 44% of the expected number of Bonferroni-significant loci we were powered to replicate, at least one from each cluster, including an intronic variant in patatin-like phospholipase domain-containing protein 3 (PNPLA3; rs66812091) and non-alcoholic fatty liver disease, a previously reported additive association. We present evidence suggesting that the association is recessive instead (odds ratio [OR] = 1.3, recessive p = 2 × 10-12, additive p = 2 × 10-11, dominance deviation p = 3 × 10-2, and FinnGen recessive OR = 1.3 and p = 6 × 10-12). We identified a novel protective recessive association between a missense variant in SGLT4 (rs61746559), a sodium-glucose transporter with a possible role in the renin-angiotensin-aldosterone system, and hypertension (OR = 0.2, p = 3 × 10-8, dominance deviation p = 7 × 10-6). These results motivate interrogating recessive effects on common diseases more widely.

Study on MTHFR (C677T & A1298C) Gene Polymorphisms in the Condition of Glucose Intolerance During Pregnancy

INTRODUCTION

Gestational diabetes mellitus (GDM) is a prevalent medical complication in pregnancy, characterized by glucose intolerance. The global expected prevalence of GDM is approximately 15.1%. This study builds upon previous research by investigating elevated hematological parameters and exploring MTHFR gene polymorphisms in GDM.

MATERIALS AND METHODS

This study included 304 pregnant women, comprising 152 patients with GDM and an equal number of normal pregnant women. Employing PCR-RFLP techniques, we identified MTHFR gene polymorphisms (C677T & A1298C) associated with gestational diabetes.

RESULTS

Significant associations were found in gestational age and platelet count, indicating their relevance to GDM risk. The odds ratios for both MTHFR A1298C (p value: 0.034; OR = 0.7; 95% CI: 0.5021-0.9758) and MTHFR C677T (p value: 0.008; OR = 0.5453; 95% CI: 0.3292-0.9011) gene polymorphisms demonstrated an increased risk of GDM development.

CONCLUSION

The study reveals that elevated platelet count and polymorphs increase the risk of developing GDM in pregnant women. Gestational age also plays a role. The study also finds a link between the MTHFR C677T SNP and the MTHFR A1298C gene polymorphism and the risk of gestational diabetes in Andhra Pradesh. This gives us new information about genetic and hematological factors.

Interaction of MTHFR polymorphism with PAX1 methylation in cervical cancer

We aimed to investigate the roles and interaction effects of high-risk human papillomavirus (HR-HPV) infection, methyltetrahydrofolate reductase (MTHFR) polymorphism, and paired box gene 1 (PAX1) methylation in cervical intraepithelial neoplasia (CIN) and cervical cancer. Polymerase chain reaction was used to detect MTHFR polymorphism and PAX1 methylation; Mantel-Haenszel and Spearman's rank correlation tests were used to analyze the trends and correlations. Forty cases each of normal control (NC), CIN I, and CIN II/III and 9 squamous cell carcinoma (SCC) cases were enrolled. Increase in age increases the risk of cervical cancer. The HR-HPV infection rate, MTHFR mutation rate, and PAX1 methylation rate in CIN I, CIN II/III, and SCC groups were significantly higher than those in the NC group (P < 0.05). The above-mentioned rates gradually increased with the degree of cervical lesions. Moreover, HR-HPV infection, MTHFR polymorphism, and PAX1 methylation increased the risk of both CIN and cancer. A positive additive interaction was observed between PAX1 methylation and MTHFR polymorphism across different cervical lesion groups, whereas no interaction was found between HR-HPV infection and PAX1 methylation in lesion progression.

Impact of Alterations in Homocysteine, Asymmetric Dimethylarginine and Vitamins-Related Pathways in Some Neurodegenerative Diseases: A Narrative Review

Hyperhomocysteinemia (HHcy) influences the development and progression of neurodegenerative disorders in different ways. Homocysteine (Hcy) metabolism is related to that of asymmetric dimethylarginine (ADMA) and group B vitamins. The breakdown of the pathway involving nitric oxide (NO) and ADMA can be considered one of the causes of endothelial alteration that represents a crucial step in the development of several neurodegenerative disorders. Deficiencies of vitamins other than group B ones, such as D and A, have also been associated with central nervous system disorders. The aim of this narrative review is to describe the link between HHcy, ADMA, and vitamins in Parkinson's disease (PD), Alzheimer's disease (AD), and multiple sclerosis (MS) in terms of dysfunctional pathways and neuropathological processes, performing a literature search from 2015 to 2025 on PubMed. This review also provides an overview of the effects of vitamin supplementation on neurodegenerative diseases. The alteration of pathways involving NO production can lead to HHcy and elevated ADMA concentrations, causing neurodegeneration through various mechanisms, while vitamin supplementation has been shown to reduce Hcy levels, although with conflicting results about the improvement in clinical symptoms. Further studies are needed to develop optimal combined therapeutic strategies.

Homocysteine, Nutrition, and Gut Microbiota: A Comprehensive Review of Current Evidence and Insights

Homocysteine, a sulfur-containing amino acid, is an intermediate product during the metabolism of methionine, a vital amino acid. An elevated concentration of homocysteine in the plasma, named hyperhomocysteinemia, has been significantly related to the onset of several diseases, including diabetes, multiple sclerosis, osteoporosis, cancer, and neurodegenerative disorders such as dementia, Alzheimer's and Parkinson's diseases. An interaction between metabolic pathways of homocysteine and gut microbiota has been reported, and specific microbial signatures have been found in individuals experiencing hyperhomocysteinemia. Furthermore, some evidence suggests that gut microbial modulation may exert an influence on homocysteine levels and related disease progression. Conventional approaches for managing hyperhomocysteinemia typically involve dietary interventions alongside the administration of supplements such as B vitamins and betaine. The present review aims to synthesize recent advancements in understanding interventions targeted at mitigating hyperhomocysteinemia, with a particular emphasis on the role of gut microbiota in these strategies. The emerging therapeutic potential of gut microbiota has been reported for several diseases. Indeed, a better understanding of the complex interaction between microbial species and homocysteine metabolism may help in finding novel therapeutic strategies to counteract hyperhomocysteinemia.

Impact of Nutrition on the Gut Microbiota: Implications for Parkinson's Disease

Parkinson's disease (PD) is a multifactorial neurodegenerative disease that is characterized by the degeneration of dopaminergic neurons in the substantia nigra pars compacta and by the anomalous accumulation of α-synuclein aggregates into Lewy bodies and Lewy neurites. Research suggests 2 distinct subtypes of PD: the brain-first subtype if the pathology arises from the brain and then spreads to the peripheral nervous system (PNS) and the body-first subtype, where the pathological process begins in the PNS and then spreads to the central nervous system. This review primarily focuses on the body-first subtype. The influence of the gut microbiota on the development of PD has been the subject of growing interest among researchers. It has been suggested that gut inflammation may be closely associated with pathogenesis in PD, therefore leading to the hypothesis that gut microbiota modulation could play a significant role in this process. Nutrition can influence gut health and alter the risk and progression of PD by altering inflammatory markers. This review provides an overview of recent research that correlates variations in gut microbiota composition between patients with PD and healthy individuals with the impact of certain nutrients and dietary patterns, including the Mediterranean diet, the Western diet, and the ketogenic diet. It explores how these diets influence gut microbiota composition and, consequently, the risk of PD. Last, it examines fecal transplantation and the use of prebiotics, probiotics, or synbiotics as potential therapeutic strategies to balance the gut microbiome, aiming to reduce the risk or delay the progression of PD.

Effects of Methylenetetrahydrofolate Reductase Polymorphism on Clinical Features of High-Risk Psychosis Before Schizophrenia

OBJECTIVE

High-risk psychosis before schizophrenia includes individuals at clinical high risk (CHR) and genetic high risk (GHR). Methylenetetrahydrofolate Reductase (MTHFR) gene variants have been identified as risk factors for schizophrenia onset and symptom severity, though the effects of these polymorphisms in high-risk individuals remain unexplored. This study investigated the impact of MTHFR polymorphisms on clinical features of high-risk psychosis. We hypothesized that MTHFR variants may influence the progression of high-risk psychosis before schizophrenia.

METHODS

A total of 163 individuals were enrolled, comprising 76 healthy controls, 31 GHR, and 56 CHR. MTHFR polymorphisms (C677T, A1298C, and G1793A) were detected. The MATRICS Consensus Cognitive Battery was administered to assess cognitive ability. Additional recorded clinical features included sex, age, family history, cognitive scores, and the Structured Interview for Psychosis Risk Syndromes (SIPS) scores.

RESULTS

Higher MTHFR polymorphism levels were observed in high-risk individuals at the C677T site (p=0.006) and in multi-site variant analysis (p=0.012) compared to controls. Stratified by sex, both males and females showed similar increases in MTHFR polymorphism. Cognitive ability scores decreased in the high-risk group with an increase in MTHFR variant allele amounts. In the CHR group, SIPS scores non-significantly increased with the number of variant alleles.

CONCLUSION

Increased MTHFR polymorphism was associated with the risk progression of schizophrenia, being more pronounced in males than in females. Higher amounts of hypofunctional MTHFR variants tended to decrease the cognitive ability in both high-risk and healthy subjects, while higher risk levels are observed in CHR subjects.

An Allele of the MTHFR one-carbon metabolism gene predicts severity of COVID-19

While the public health burden of SARS-CoV-2 infection has lessened due to natural and vaccine-acquired immunity, the emergence of less virulent variants, and antiviral medications, COVID-19 continues to take a significant toll. There are > 10,000 new hospitalizations per week in the U.S., many of whom develop post-acute sequelae of SARS-CoV-2 (PASC), or "long COVID", with long-term health issues and compromised quality of life. Early identification of individuals at high risk of severe COVID-19 is key for monitoring and supporting respiratory status and improving outcomes. Therefore, precision tools for early detection of patients at high risk of severe disease can reduce morbidity and mortality. Here we report an untargeted and longitudinal metabolomic study of plasma derived from adult patients with COVID-19. One-carbon metabolism, a pathway previously shown as critical for viral propagation and disease progression, and a potential target for COVID-19 treatment, scored strongly as differentially abundant in patients with severe COVID-19. A follow-up targeted metabolite profiling revealed that one arm of the one-carbon metabolism pathway, the methionine cycle, is a major driver of the metabolic profile associated with disease severity. The methionine cycle produces S-adenosylmethionine (SAM), the methyl group donor important for methylation of DNA, RNA, and proteins, and its high abundance was reported to correlate with disease severity. Further, genomic data from the profiled patients revealed a genetic contributor to methionine metabolism and identified the C677T allele of the MTHFR gene as a pre-existing predictor of disease trajectory - patients homozygous for the MTHFR C677T have higher incidence of experiencing severe disease. Our results raise the possibility that screening for the common genetic MTHFR variant may be an actionable approach to stratify risk of COVID severity and may inform novel precision COVID-19 treatment strategies.

Evaluating the Effect of Epigallocatechin Gallate (EGCG) in Reducing Folate Levels in Reproductive Aged Women by MTHFR and DHFR Genotype in Combination With Letrozole or Clomiphene

Previous epidemiological studies have suggested that green tea catechins, including Epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, may be associated with reduced serum folate levels. This is of particular interest as women of childbearing age may be consuming EGCG from tea, dietary supplements, or involved in active clinical trials studying EGCG or green tea extract. EGCG was reported to shrink uterine fibroids in preclinical and clinical studies. This observation led to the development of a multicenter NICHD-funded clinical trial to evaluate the safety of EGCG for treating women with fibroids and unexplained infertility (NCT04177693). To answer the question of whether green tea extract standardized to EGCG led to a reduction in folate, 39 women aged ≥ 18 to ≤ 40 years, with/without uterine fibroids, were evaluated. These women were randomized to receive either EGCG, EGCG + clomiphene, or EGCG + letrozole for 30 days. A daily dose of 720 mg of highly characterized green tea extract containing EGCG was used. Participants were genotyped for polymorphisms at positions 677 and 1298 in MTHFR and for the -19 bp deletion polymorphism of DHFR. During the intervention with EGCG, folate levels remained in the normal range in all subjects. Our data suggest that in reproductive-age women, a 30-day course of EGCG 720 mg daily taken alone or in combination with clomiphene citrate or letrozole (for 5 days) is well-tolerated and is not associated with folate deficiency even in the presence of MTHFR and/or DHFR polymorphisms known to negatively impact folate synthesis. Trial Registration: Clinical trial: NCT01311869.

Association of methylenetetrahydrofolate reductase (MTHFR) C677T, MTHFR A1298C, and CYP3A4 A290G gene polymorphisms with clinical outcomes of HLA-matched sibling allogeneic hematopoietic cell transplantation in an Egyptian patient/donor cohort

The impact of non-HLA drug-metabolizing gene polymorphisms on post-transplant outcomes is well recognized. We aimed to evaluate the impact of 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T and A1982C and CYP3A4 A290G polymorphisms on the outcomes of patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) from fully matched siblings. Using PCR-RFLP and according to DNA availability, MTHFR and CYP3A4-V polymorphisms were evaluated. In total 60 patient/donor pairs were investigated. The MTHFR genotypes exhibited similar frequencies in both patients and donors; the MTHFR wild-type in patients correlated with a trend towards reduced incidence of GVHD and improved overall survival rates. Most patients (84.9 %) and donors (76.8 %) had CYP3A4 A wild type. Acute GVHD occurred only in patients with the wild type (10/45 AA vs 0/8 AG or GG) and 9/43 vs 1/13 in recipients from donors with AA vs. AG + GG. GVHD prophylaxis regimens that do not include methotrexate demonstrated a 5.5-fold increased risk of acute GVHD (p = 0.03). Alternative conditioning regimens to Busulphan/Cyclophosphamide exhibited a 19.1-fold increase in the risk of transplant-related mortality (TRM), with statistical significance (p = 0.007). Severe oral mucositis was correlated with male gender (p = 0.03) and a diagnosis of leukaemia (p = 0.007). Renal toxicity is correlated with an age of ≥ 18 years (p = 0.04) and male gender (p = 0.04). In conclusion, methotrexate in GVHD prophylaxis correlates with a reduced risk of GVHD, while the Busulphan/Cyclophosphamide conditioning regimen is linked to a lower incidence of TRM. Although statistical significance was not achieved due to the predominance of the CYP3A4 wild type, its nearly exclusive association with GVHD may hold clinical significance. Therefore, genotyping patients and adjusting the CsA dose for individuals with the CYP3A4 wild type is recommended.

Folic and folinic acid load tests for dynamic assessments of compliance and metabolism in folate deficiency and hyperhomocysteinaemia patients unresponsive to high-dose folate replacement

We describe the utility of 'folic and folinic acid load tests' in the investigation of a 26-year-old woman with persistently low serum folate and moderate hyperhomocysteinaemia unresponsive to folic acid supplements. Serum folate, plasma 5-methyltetrahydrofolate (5-MTHF), red cell 5-MTHF and plasma total homocysteine at baseline, 2-h, 4-h and 2- or 4-days (if applicable) post administration of a large dose of oral folic acid, or oral or parenteral folinic acid were measured. The tests confirmed non-compliance but also suggested an unsuspected possible defect in the folate pathway based on differential response to folic versus folinic acid supplements. The folic and folinic acid load tests identify non-compliance and can help identify possible defects related to the absorption, transportation, or metabolism of folate.

Omics Data Integration Uncovers mRNA-miRNA Interaction Regions in Genes Associated with Chronic Venous Insufficiency

Background/Objectives: Chronic venous insufficiency (CVI), a chronic vascular dysfunction, is a common health problem that causes serious complications such as painful varicose veins and even skin ulcers. Identifying the underlying genetic and epigenetic factors is important for improving the quality of life of individuals with CVI. In the literature, many genes, variants, and miRNAs associated with CVI have been identified through genomic and transcriptomic studies. Despite molecular pathogenesis studies, how the genes associated with CVI are regulated by miRNAs and the effect of variants in binding regions on expression levels are still not fully understood. In this study, previously identified genes, variants, and miRNAs associated with CVI, common variants in the mRNA-miRNA binding regions, were investigated using in silico analyses. Methods: For this purpose, miRNA research tools, MBS (miRNA binding site) database, genome browsers, and the eQTL Calculator in the GTEx portal were used. Results: We identified SNVs associated with CVI that may play a direct role in the miRNA-mediated regulation of the ZNF664, COL1A2, HFE, MDN, MTHFR, SRPX, TDRD5, TSPYL4, VEGFA, and APOE genes. In addition, when the common SNVs in the mRNA binding region of 75 unique CVI related-miRNAs in five candidate genes associated with CVI were examined, seven miRNAs associated with the expression profiles of ABCA1, PIEZO1, and CASZ1 genes were identified. Conclusions: In conclusion, the relationship between genetic markers identified in the literature that play a role in the pathogenesis of the CVI and the expression profiles was evaluated for the first time in the mRNA-miRNA interaction axis.

Folic Acid and Methyltetrahydrofolate Supplementation in the Mthfr677C>T Mouse Model with Hepatic Steatosis

BACKGROUND/OBJECTIVES

The MTHFR677C>T gene variant results in a thermolabile MTHFR enzyme associated with elevated plasma homocysteine in TT individuals. Health risks associated with the TT genotype may be modified by dietary and supplemental folate intake. Supplementation with methyltetrahydrofolate (methylTHF) may be preferable to folic acid because it is the MTHFR product, and does not require reduction by DHFR to enter one-carbon folate metabolism. In the Mthfr677C>T mouse model for this variant, female 677TT (TT) mice have an increased incidence of hepatic steatosis. The objective of this study was to compare the effects of methylTHF and folic acid supplementation on hepatic steatosis and one-carbon metabolism in this model.

METHODS

Male and female C57BL/6J 677CC (CC) and TT mice were fed control (CD), 5xmethylTHF-supplemented (MFSD), or 5xfolic-acid-supplemented (FASD) diets for 4 months. Liver sections were assessed for steatosis by Oil Red O staining. One-carbon metabolites were measured in the liver and plasma. MTHFR protein expression was evaluated in the liver.

RESULTS

MFSD had no significant effect on plasma homocysteine, liver SAM/SAH ratios, or hepatic steatosis in males or females as compared to CD. MTHFR protein increased in MFSD TT female liver, but remained <50% of the CC. FASD had no effect on plasma homocysteine but it decreased the liver MTHFR protein and SAM/SAH ratios, and increased hepatic steatosis in CC females.

CONCLUSIONS

MethylTHF and folic acid supplementation had limited benefits for TT mice, while folic acid supplementation had negative effects on CC females. Further investigation is required to determine if these effects are relevant in humans.

MTHFR Gene Polymorphisms and DNA Methylation in Idiopathic Spontaneous Preterm Birth

Background and Objectives: Preterm birth (PTB) is a complex condition with various contributing factors, including genetic and epigenetic influences such as DNA methylation. Methylenetetrahydrofolate reductase (MTHFR) plays a critical role in DNA methylation and the remethylation of homocysteine. This study aimed to investigate the association between maternal MTHFR C677T and A1298C polymorphisms, LINE-1 DNA methylation levels, and the risk of idiopathic spontaneous preterm birth (SPTB) in Caucasian women from Croatia and Slovenia. Materials and Methods: A total of 50 women with SPTB (<34 weeks of gestation) and 50 control women were included in the study. MTHFR polymorphisms were analyzed using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), and LINE-1 DNA methylation levels were quantified using the MethyLight method. Results: The study found no significant differences in MTHFR C677T and A1298C polymorphisms' genotype or allele frequencies between women with SPTB and controls. Additionally, no statistical significance of LINE-1 DNA methylation was found between the genotypes of the MTHFR polymorphisms analyzed. Conclusions: The study suggests no conclusive association between MTHFR C677T and A1298C polymorphisms, LINE-1 DNA methylation, and SPTB in Croatian and Slovenian women. Considering prior evidence connecting MTHFR polymorphisms, hyperhomocysteinemia, and PTB, the lack of homocysteine measurements and unassessed impact of folate or vitamin B supplementation limit the conclusions.

Personalized nutrition and precision medicine in perimenopausal women: A minireview of genetic polymorphisms COMT, FUT2, and MTHFR

This mini-review explores the potential of precision medicine and personalized nutrition in addressing health challenges faced by perimenopausal women, focusing on the role of genetic polymorphisms in key metabolic pathways. Specifically focus on the single nucleotide polymorphisms (SNPs) in the COMT, FUT2, and MTHFR genes, which influence neurotransmitter metabolism, gut microbiota composition, and folate homeostasis, respectively. These polymorphisms are critical in modulating hormonal fluctuations, metabolic imbalances, and nutrient absorption during perimenopause. The review highlights the impact of COMT rs4680 on stress response and mood disorders, FUT2 rs602662 and rs601338 on vitamin B12 absorption and cortisol metabolism, and MTHFR rs1801133 and rs1801131 on homocysteine levels and cardiovascular risk. Furthermore, the integration of machine learning in precision medicine is discussed, offering insights into how genetic data can optimize personalized interventions. This approach enables targeted nutritional and therapeutic strategies to mitigate the metabolic and psychological effects of perimenopause. Overall, this review underscores the importance of incorporating genetic testing into preventive care for perimenopausal women to enhance quality of life and promote healthy aging.

Genome-Wide Association Study Identifies Genetic Polymorphisms for Folate-Related Biomarkers in Chinese Preconception Women

BACKGROUND

Single-nucleotide polymorphism (SNP) allele frequencies, dietary habits, and folate status and their associations vary across ethnic populations. Little is known about the SNPs accounting for variations of folate-related biomarkers for Chinese preparing-for-pregnant females.

OBJECTIVES

We aimed to identify SNPs contributing to RBC and serum folate, vitamin B-12, and homocysteine concentrations in Chinese female preconception population.

METHODS

A genome-wide association study was conducted on 1000 randomly selected preconception Chinese women from the Shanghai Preconception Cohort. SNPs were genotyped using Illumina chips, and associations with biomarkers were assessed using simple linear regression models under the assumption of an additive genetic model. Genome-wide significance was considered at P < 10-7.

RESULTS

The MTHFR rs1801133 was the major genetic coding variant contributing to RBC folate, serum folate, and homocysteine concentrations (P = 2.28 × 10-16; P = 8.85 × 10-8, and P = 2.46 × 10-13, repsectively). It is associated with increased RBC folate (β: 0.154 per additional risk allele after log transform), decreased serum folate (β: -0.951 per additional risk allele), and increased serum homocysteine concentrations (β: 1.153 per additional risk allele). The predominant SNP associated with serum folate was rs147162222 in NTRK2 (P = 2.55 × 10-8), although that associated with homocysteine was rs77025184 located between PDE7B and LINC00271 (P = 4.91 × 10-17). For vitamin B-12, FUT2 rs1047781 was the dominant genetic variant (P = 1.59 × 10-10). The numbers of signals with a P value of <10-7 for RBC folate, serum folate, vitamin B-12, and homocysteine were 12, 18, 8, and 614, respectively.

CONCLUSIONS

This study represents the first genome-wide association study focusing on folate-related biomarkers in a Chinese preparing-for-pregnant female population. The contributions of dominent SNPs to each biomarker are partly different from other populations. The rs1801133 (C677T) in MTHFR is the predominant genetic variant contributing to RBC folate and rs1047781 (A385T) in FUT2 as the primary one explaining vitamin B-12. Notably, the intronic rs147162222 and noncoding rs77025184 are the predominant SNPs for serum folate and homocysteine, respectively.

Associations between maternal MTHFR polymorphisms and embryological outcomes in Korean patients with infertility undergoing IVF/ICSI cycles

OBJECTIVE

Methylenetetrahydrofolatereductase (MTHFR) is important for folate metabolism, which is involved in DNA synthesis and cell growth. However, the relationship between Maternal MTHFR polymorphisms and outcomes in assisted reproduction remains controversial. This is the first study to explore the effect of MTHFR polymorphisms on the embryological outcomes in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles in Korean patients with infertility.

MATERIALS AND METHODS

This retrospective cohort study included 173 women who underwent MTHFR genotyping between July, 2021 and June, 2022. The embryologic outcomes of 301 IVF/ICSI cycles were compared between groups according to MTHFR polymorphisms using ANOVA and Chi-square test.

RESULTS

Oocyte maturation rates were 80.0%, 75.0%, and 71.4% for MTHFR 677CC, 677CT, and 677TT, respectively. Cleaved embryo formation and transplantable embryo rates were comparable across various maternal MTHFR 677 genotypes. Good-quality embryo (GQE) rate was higher for MTHFR 677CT than those for 677CC and 677TT (40.0% vs. 29.4%, p = 0.001 and 40.0% vs. 33.3%, p = 0.025, respectively). When analyzing the combined MTHFR genotypes, the oocyte maturation rate was significantly lower in 677TT than in 677CC 1298AA/677CC 1298AC and 677CC 1298CC/677CT 1298AA/677CT 1298AC (71.4% vs. 76.7%, p = 0.012 and 71.4% vs. 75.7%, p = 0.029, respectively). The MTHFR 677CC/1298CC, 677CT/1298AA, and 677CT/1298AC genotypes had the highest GQE rates.

CONCLUSIONS

MTHFR 677TT genotype, which had the lowest enzymatic activity, had the lowest oocyte maturation rate. The combined MTHFR 677CC/1298CC, 677CT/1298AA, and 677CT/1298AC genotypes with intermediate enzyme activities had higher GQE rates. However, no differences were observed in the transplantable embryo rate between MTHFR genotypes.

Guidance and Position of RINN22 regarding Precision Nutrition and Nutriomics

BACKGROUND

Precision nutrition is based on the integration of individual's phenotypical and biological characteristics including genetic variants, epigenetic marks, gut microbiota profiles, and metabolite fingerprints as well as medical history, lifestyle practices, and environmental and cultural factors. Thus, nutriomics areas including nutrigenomics, nutrigenetics, nutriepigenetics, nutrimetabolomics, and nutrimetagenomics have emerged to comprehensively understand the complex interactions between nutrients, diet, and the human body's molecular processes through precision nutrition.

SUMMARY

This document from the Ibero-American Network of Nutriomics and Precision Nutrition (RINN22; https://rinn22.com/) provides a comprehensive overview of the concepts of precision nutrition approaches to guide their application in clinical and public health as well as establish the position of RINN22 regarding the current and future state of precision nutrition.

KEY MESSAGES

The progress and participation of nutriomics to precision nutrition is an essential pillar for addressing diet-related diseases and developing innovative managing strategies, which will be promoted by advances in bioinformatics, machine learning, and integrative software, as well as the description of specific novel biomarkers. In this context, synthesizing and critically evaluating the latest developments, potential applications, and future needs in the field of nutrition is necessary with a holistic perspective, incorporating progress in omics technologies aimed at precision nutrition interventions. This approach must address and confront healthy, social, food security, physically active lifestyle, sanitation, and sustainability challenges with preventive, participatory, and predictive strategies of personalized, population, and planetary nutrition for a precision tailored health.

Investigating the Matrix of Factor V Leiden (G1691A), Factor II Prothrombin (G2021A), MTHFR C677T and A1298G Polymorphisms in Greek Population: A Preliminary Study

BACKGROUND

Thrombophilia, characterized by an increased risk of thrombosis, can result from genetic polymorphisms in clotting factors. This study aims to investigate the prevalence of factor V Leiden (G1691A), factor II prothrombin (G20210A), and MTHFR (C677T and A1298C) polymorphisms in a Greek population, evaluating not only their association with thrombophilia, but also broader health implications.

METHODS

We conducted a cross-sectional study involving one hundred apparently healthy adults from Thessaloniki, Greece. After obtaining informed consent, DNA was isolated and analyzed using real-time PCR to detect the frequencies of the aforementioned polymorphisms.

RESULTS

The genetic distribution of the examined polymorphisms aligns closely with that observed in Northern Europe. Factor V Leiden (FVL) and prothrombin G20210A mutations were predominantly wild types, with a small percentage showing heterozygous mutations. The MTHFR C677T and A1298C polymorphisms showed a higher variation in allele frequency. Certain lifestyle factors such as smoking and high body mass index were significantly associated with the occurrence of combined MTHFR genotypes, suggesting an interaction between genetic and environmental risk factors. Family cancer and cardiovascular history was significantly associated with combined FVL and prothrombin G20210A and MTHFR polymorphism heterozygous carriers.

CONCLUSIONS

Our findings indicate that these genetic polymorphisms are not only pivotal in understanding thrombophilia but also have broader implications for cardiovascular disease and cancer. This study highlights the need for further research into the combined effects of genetic and epigenetic factors on health, which could lead to improved screening and personalized preventive healthcare strategies.

Impact of genetic variations of gene involved in regulation of metabolism, inflammation and coagulation on pathogenesis of cardiac injuries associated with COVID-19

BACKGROUND

SARS-CoV-2 infection can result in long-term chronic cardiovascular (CV) damage after the acute phase of the illness. COVID-19 frequently causes active myocarditis, SARS-CoV-2 can directly infect and kill cardiac cells, causing severe pathology and dysfunction across the organs and cells. Till now, the pathogenesis of COVID-19-associated cardiac injuries has not been understood, but there are several factors that contribute to the progression of cardiac injuries, such as genetic, dietary, and environmental. Among them ranges of host genetic factor including metabolizing, inflammation, and coagulation related genes have a role to contribute the cardiac injuries induced by COVID-19. Hereditary DNA sequence variations contribute to the risk of illness in almost all of these diseases. Hence, we comprehended the occurrence of genetic variations of metabolizing, inflammation and coagulation-related genes in the general population, their expression in various diseases, and their impact on cardiac injuries induced by COVID-19.

METHOD

We utilized multiple databases, including PubMed (Medline), EMBASE, and Google Scholar, for literature searches.

DESCRIPTION

The genes involved in metabolism (APOE, MTHFR), coagulation (PAI-1, ACE2), and immune factors (CRP, ESR, and troponin I) may have a role in the progression of COVID-19-associated cardiac injuries. The risk factors for CVD are significantly varied between and within different regions. In healthy individuals, the ACE I allele is responsible for the predisposition to CAD, but the ACE D haplotype is responsible for susceptibility and severity, which ultimately leads to heart failure. Patients who carry the T allele of rs12329760 in the TMPRSS2 gene are at risk for developing the severe form of COVID-19. IL-6 (rs1800796/rs1800795) polymorphism is associated with an increased mortality rate and susceptibility to severe COVID-19 disease. While the putative role of IL-6 associated with chronic, inflammatory diseases like cardiac and cerebrovascular disease is well known.

CONCLUSION

The occurrence of genetic variations in the ACE-2, AGT, DPP-IV, TMPRSS2, FUIRN, IL-4, IL-6, IFN-γ, and CYP2D6 genes is varied among different populations. Examining the correlation between these variations and their protein levels and cardiac injuries induced by COVID-19 may provide valuable insights into the pathogenesis of cardiac injuries induced by COVID-19.

Factor V Leiden (R506Q), Prothrombin G20210A, and MTHFR C677T Variants and Thrombophilia in Qatar Biobank Participants: A Case Control Study

Background: Thrombophilia, a predisposition to develop blood clots, is very common and can have serious sequelae. Aim: This study aimed to determine the prevalence of three thrombophilia-related genetic variants-factor V Leiden (FVL), prothrombin (F2) G20210A, and MTHFR C677T-in the Qatari population and their associations with self-reported thrombosis. Methods: We analysed samples from 408 Qatari participants [304 controls and 104 with self-reported thrombosis (deep vein thrombosis, pulmonary embolus, or ischaemic stroke)] from the Qatar Biobank. FVL (rs6025), F2 (rs1799963), and MTHFR (rs1801133) variants were genotyped using TaqMan assays. Results: Participants with self-reported thrombosis were older and more likely to be female. FVL A allele carriage (GA + AA vs. GG) was significantly higher in thrombosis cases (OR 3.6, p = 0.0002). In addition, individuals carrying FVL AA and GA genotypes had a lower mean platelet volume on average than those with the GG genotype (p = 0.03). MTHFR C677T did not show a similar association, and the F2 G20210A variant was too rare for analysis. Conclusions: There were significant differences in FVL A allele carriage between individuals with a history of thrombosis and the control group. Future research should explore the complex interplay between genetics and environment in thrombosis risk within this population.

Serum molecules of the folate-driven one-carbon cycle as indicators of depressive tendencies in the elderly

Aims

The folate-driven one-carbon (1C) cycle plays a significant role in the occurrence and development of depression. This study aimed to examine the potential of important molecules of the folate-driven 1C cycle as biomarkers for depressive tendency.

Methods

Ninety-five serum samples from older adults (age >60 years) were collected for this study. We quantified the concentrations of key metabolites and coenzymes of the folate-driven 1C cycle using Ultra-Performance Liquid Chromatography coupled with Tandem Mass Spectrometry (UPLC-MS/MS) and familiar clinical liver and kidney indicators in serum. Based on the differences in Hamilton Depression Rating Scale (HAMD)-17 scores, we compared the concentrations of measured molecules between elderly individuals with low and high levels of depression defined as HAMD-17 scores of 0-7 and 8-24, respectively. We also analyzed the concentration ranges of these molecules reflecting the level of depressive tendencies in the cohort.

Results

Our results showed significant variations in serum folate concentrations, SAM (S-adenosylmethionine), TBA (total bile acid), and SAM/SAH (S-enosylhomocysteine) ratios in elderly individuals with different HAMD-17 scores. Serum folate concentrations below 15.5 nmol/L and SAM/SAH ratios below 13.0 exhibited elevated levels of depressive tendency experienced among the participants.

Conclusions

The concentrations of serum folate, SAM, TBA, and SAM/SAH ratios might be used as indicators of depressive tendencies in the elderly population. A serum folate concentration of 15.5 nmol/L and a SAM/SAH ratio of 13.0 might be critical thresholds for indicating depressive tendencies in the Chinese elderly population.

Correlating COVID-19 severity with biomarker profiles and patient prognosis

COVID-19's long-lasting and complex impacts have become a global concern, with diverse clinical outcomes. This study evaluated 226 participants to understand the clinical spectrum of COVID-19/Long COVID (LC), exploring how disease severity correlates with sociodemographic factors and biomarkers. Determinants related to COVID-19 severity included age (P < 0.001), lower education (P < 0.001), ethnicity (P = 0.003), overweight (P < 0.001), MTHFR gene rs1801133 (P = 0.035), cardiovascular diseases (P = 0.002), diabetes mellitus (DM) (P = 0.006), Factor VIII (FVIII) (P = 0.046), von Willebrand factor (VWF) (P = 0.002), and dimer D (DD) (P < 0.001). Six months later, in a portion of the monitored participants, a significant reduction in FVIII (P < 0.001), VWF (P = 0.002), and DD (P < 0.001) levels was observed, with only DD returning to normal values. Different systemic sequelae were identified, with higher incidences of joint pain and myalgia in participants with a clinical history of DM, chronic lung disease (CLD) and sustained high interleukin 6 values in the convalescent phase. CLD, COVID-19 severity and high DD levels increased the risk of developing dyspnea and palpitations. Women were more likely to develop lower limb phlebitis long-term, while sustained elevated FVIII in the convalescent phase was associated with an increased risk of swelling. Regular physical activity had a protective effect against swelling. This study highlights factors contributing to COVID-19 severity/LC, emphasizing endothelial cell activation as a potential mechanism.

Polymorphism of Folate Metabolism Genes among Ethnic Kazakh Women with Preeclampsia in Kazakhstan: A Descriptive Study

INTRODUCTION

Preeclampsia is a severe multifactorial complication of pregnancy. Studies found associations between folate metabolism genes' polymorphisms and preeclampsia. However, investigations in this field are limited among Asian populations. Thus, the study's aim was to evaluate the prevalence of methionine synthase (MTR), methionine synthase reductase (MTRR), and methylenetetrahydrofolate reductase (MTHFR) genes' polymorphisms among ethnic Kazakh women with preeclampsia.

METHODS

This was a retrospective study involving 4246 patients' data for the period of 2018-2022. Identification of MTR, MTRR, and MTHFR genes' polymorphism was performed via PR-PCR. Peripheral blood samples were obtained for the analyses. In total, 4246 patients' data of Kazakh ethnicity with preeclampsia at >20 weeks gestational age who had undergone an investigation to identify polymorphisms of the folate metabolism pathway genes for the period of 5 years were included in this study.

RESULTS

The most common and prevalent mutation was the MTRR A66G polymorphism: 24.5% of all tested patients with preeclampsia had the MTRR A66G polymorphism. It was highest among the 35-39 age group participants. The second most prevalent was the MTHFR C677T polymorphism: 9% of women with preeclampsia had the MTHFR C677T mutation. It was highest among women aged 30-34. There was a rare association of the MTR A2756G mutation with preeclampsia among the study participants.

CONCLUSIONS

The identified levels of MTRR A66G and MTHFR C677T polymorphisms among the study participants suggest the importance of evaluating MTRR and MTHFR polymorphisms in women with preeclampsia. The role of the MTR A2756G polymorphism in the development of preeclampsia needs to be further investigated.

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.

Novel analysis of functional relationship linking moyamoya disease to moyamoya syndrome

Objective

The aim of this study was to elucidate the genetic pathways associated with Moyamoya disease (MMD) and Moyamoya syndrome (MMS), compare the functional activities, and validate relevant related genes in an independent dataset.

Methods

We conducted a comprehensive search for genetic studies on MMD and MMS across multiple databases and identified related genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichments analyses were performed for these genes. Commonly shared genes were selected for further validation in the independent dataset, GSE189993. The Sangerbox platform was used to perform statistical analysis and visualize the results. P＜0.05 indicated a statistically significant result.

Results

We included 52 MMD and 51 MMS-related publications and identified 126 and 51 relevant genes, respectively. GO analysis for MMD showed significant enrichment in cytokine activity, cell membrane receptors, enzyme binding, and immune activity. A broader range of terms was enriched for MMS. KEGG pathway analysis for MMD highlighted immune and cellular activities and pathways related to MMS prominently featured inflammation and metabolic disorders. Notably, nine overlapping genes were identified and validated. The expressions of RNF213, PTPN11, and MTHFR demonstrated significant differences in GSE189993. A combined receiver operating characteristic curve showed high diagnostic accuracy (AUC = 0.918).

Conclusions

The findings indicate a close relationship of MMD with immune activity and MMS with inflammation, metabolic processes and other environmental factors in a given genetic background. Differentiating between MMD and MMS can enhance the understanding of their pathophysiology and inform the strategies for their diagnoses and treatment.

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.

Association between Methylenetetrahydrofolate Reductase (MTHFR) and 5-Methyltetrahydrofolate-Homocysteine Methyltransferase Reductase (MTRR) Polymorphisms in Iraqi Patients with COVID-19

Background

The methylenetetrahydrofolate reductase (MTHFR) gene is an essential gene in the metabolism of folate-homocysteine. Recently, the level of homocysteine was found to be a significant marker in the follow-up of COVID-19 infection. Thus, this study aimed to detect the effect of genetic polymorphisms for single nucleotide polymorphisms (SNPs) (c.66A>G, c.1298A>C, and c.677CT) on COVID-19 infection.

Methods

Blood samples were collected from 270 patients with COVID-19 in the medical center of Al-Shifa (Baghdad, Iraq) from November 2020 to March 2021. Tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) technique was used for the detection of genotypes of SNPs. The odds ratio (OR) was used to detect the relationship between SNPs and COVID-19 infections. Haplotype analysis was performed by SHEsis software.

Results

There was a significant difference between mild/moderate cases and severe/critical cases for ages (35-45), (46-55), and (56-65) years (P<0.0001, P=0.01, and P=0.006, respectively). The results showed significant differences in the T allele for SNP c.677>C (P<0.0001 and OR=4.58). The C allele for SNP c.1298A>C indicated significant differences (P<0.001 and OR=3.15). Besides, the G allele for SNP c.677C>T showed significant differences (P<0.001 and OR=6.64). Consequently, these SNPs showed a predisposition to the development of COVID-19 infection. With regard to the C-A-A, T-A-A and T-C-G haplotypes indicated significant differences between the control and patient groups. The C-A-A was related to a decreased risk and indicated a protective effect against COVID-19 infection development (P<0.0001 and OR=0.218). The increased risk was associated with T-A-A and T-C-G haplotypes and indicated the risk impact on COVID-19 infection development (P<0.0001, P=0.004, and OR=15.5, OR=6.772, respectively). Furthermore, the linkage disequilibrium (LD) for SNPs was studied, and the complete D' value was 99.

Conclusion

The genetic polymorphisms of SNPs (c.66A>G, c.1298A>C, and c.677C>T) in the Iraqi population were associated with COVID-19 infection.

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.

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.