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1.
Medicine (Baltimore) ; 99(40): e22614, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019481

RESUMO

BACKGROUND: The relationship between MTHFR (5, 10-methylene tetrahydrofolate reductase) gene polymorphisms and Systemic Lupus Erythematosus (SLE) has been wildly studied, but the results are still conflicting. Therefore, the purpose of this meta and pooled analysis was to identify the role of the MTHFR SNP (single nucleotide polymorphism, rs1801133) in SLE in a large sample of subjects and to assess the risk of SLE. METHODS: Data were collected from EMBASE, PubMed and China National Knowledge Infrastructure from inception to August, 2019. Summary odds ratio (OR) with 95% confidence interval (CI) was applied to assess the association. Subgroup and sensitivity analysis were performed to assess the potential sources of heterogeneity of the pooled estimation. RESULTS: We identified seven eligible studies involving 882 cases and 991 controls. MTHFR rs1801133 T carrier was significantly associated with increased risk of SLE when comparing to C allele [ORs were 1.766 (1.014-3.075) for T carrier vs CC, P = .04]. Furthermore, the results of the subgroup analysis by genotyping methods suggested that T allele significantly contributed to the risk of SLE for both by polymerase chain reaction-TaqMan (PCR-TaqMan) [10.111 (2.634-38.813) for TT vs CC, 3.467 (1.324-9.078) for CT vs CC and 3.744 (1.143-12.264) for TT vs C carrier]. Also the results of the subgroup analysis by ethnicity suggested that T allele significantly contributed to the risk of SLE for Asians [9.679 (4.444-21.082) for TT vs CC, 5.866 (3.021-11.389) for T carrier vs CC and 8.052 (3.861-16.795) for TT vs C carrier]. CONCLUSION: This cumulative meta-analysis showed that the MTHFR SNP (rs1801133) contributed to susceptibility of SLE. However, more multicentre well-designed case-control studies and larger sample sizes are exceedingly required to validate our findings in the future.


Assuntos
Lúpus Eritematoso Sistêmico/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Portador Sadio , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Medição de Risco , Sensibilidade e Especificidade
2.
Medicine (Baltimore) ; 99(35): e21558, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871871

RESUMO

BACKGROUND: As indicated by numerous studies, there exists a relationship between the polymorphism of methylenetetrahydrofolate reductase (MTHFR) and susceptibility to diabetic nephropathy (DN) in various populations; nonetheless, the findings remain inconsistent. Therefore, we carried out a meta-analysis to determine the relationship between the MTHFR gene polymorphism and DN susceptibility. MATERIALS AND METHOD: Related studies were identified from PubMed, Cochrane Library, EMBASE, and the China National Knowledge Infrastructure database (time period: from building the library to October 2019). The strength of the association was examined using odds ratios (ORs) with 95% confidence intervals (95% CIs). RESULTS: The findings illustrated that the C677T gene polymorphism was significantly associated with an enhanced susceptibility to DN compared to that with diabetes mellitus in allelic (OR = 1.64, 95% CI = 1.34-2.00, P < .001), dominant (OR = 1.85, 95% CI = 1.40-2.46, P < .001), codominant (heterozygote: OR = 1.67, 95% CI = 1.27-2.21, P < .001; homozygote: OR = 2.55, 95% CI = 1.82-3.57, P < .001), and recessive (OR = 1.89, 95% CI = 1.50-2.38, P < .001) models of the overall population. Moreover, as compared with the healthy controls, a significantly augmented susceptibility to DN was found in all 5 genetic comparison models (allelic: OR = 2.06, 95% CI = 1.58-2.67, P < .001; dominant: OR = 2.52, 95% CI = 1.73-3.69, P < .001; codominant: OR = 3.78, 95% CI = 2.50-5.70, P < .001; recessive: OR = 2.41, 95% CI = 1.96-2.97, P < .001). Furthermore, stratifying data by ethnicity revealed substantially augmented vulnerability to DN in not only Caucasian but also Asian populations. CONCLUSION: The present study suggests that the C677T polymorphism was associated with an augmented susceptibility to DN.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/epidemiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Grupo com Ancestrais do Continente Europeu/genética , Predisposição Genética para Doença , Humanos , Fatores de Risco
3.
Anticancer Res ; 40(8): 4263-4270, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727753

RESUMO

BACKGROUND/AIM: Enzymatic variants involved in fluoropyrimidine metabolism have been associated with adverse events (AEs). We assessed the association between C677T (rs1801133) and A1298 (rs1801131) methylenetetrahydrofolate reductase (MTHFR) polymorphisms and AEs in patients with first-line fluoropyrimidine-based chemotherapy. PATIENTS AND METHODS: Fifty patients with metastatic colorectal cancer were prospectively followed-up during the first 4 cycles of fluoropyrimidine-based treatment to assess AEs. Germline DNA was analyzed to determine the C677T and A1298C MTHFR polymorphisms. The associations between MTHFR polymorphisms and toxicity were examined. RESULTS: Individuals carrying at least one mutant allele of the MTHFR C677T polymorphism had increased risk to experience anemia (OR=1.69, 95% CI=1.13-2.53, p=0.005), neutropenia (OR=2.27, 95% CI=1.47-3.42, p<0.001) thrombocytopenia (OR=1.91, 95% CI=1.30-2.70, p<0.001), neuropathy (OR=1.77, 95% CI=1.16-2.70, p=0.02), diarrhea (OR=1.69, 95% CI=1.13-2.53, p=0.005), and hand-foot syndrome (OR=1.56, 95% CI=1.08-2.27, p=0.013), compared to patients carrying the wild type alleles. The presence of the mutant allele C of the MTHFR A1298C polymorphism was associated with increased risk of anemia (OR=2.75, 95% CI=1.01-7.48, p=0.02) and thrombocytopenia (OR=3.14, 95% CI=1.01-9.78, p=0.03); however, the prevalence of this allele in the sample was quite low (20%). CONCLUSION: MTHFR C677T and A1298C polymorphisms predicted toxicity in a subset of Mestizo patients with colorectal adenocarcinoma.


Assuntos
Antimetabólitos Antineoplásicos/toxicidade , Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Grupos Étnicos/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Idoso , Neoplasias Colorretais/patologia , Costa Rica , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Compostos Organoplatínicos/administração & dosagem , Estudos Prospectivos
4.
Medicine (Baltimore) ; 99(29): e21045, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32702845

RESUMO

BACKGROUND: Previous meta-analyses have explored the association between the C677T polymorphism of methyltetrahydrofolate reductase (MTHFR) and chronic kidney disease (CKD) but there were no studies with a decisive conclusion. Furthermore, the high heterogeneity among different populations is not yet interpreted. OBJECTIVES: This study used trial sequential analysis (TSA) to evaluate whether the nowadays conclusion supported by current cumulative samples. We also applied case-weighted meta-regression to explore the potential gene-environment interactions. METHODS: For the first stage of this study we conducted a case-control study involving 847 dialysis patients from 7 hemodialysis centers in Taipei during 2015 to 2018 and 755 normal controls from a health center in the Tri-Service General Hospital. The second stage combined the results from the first stage with previous studies. The previous studies were collected from PubMed, EMBASE, and Web of Science databases before January 2018. RESULTS: From the case-control study, the T allele of MTHFR C677T appeared to have a protective effect on end-stage renal disease compared with the C allele [odds ratio (OR): 0.80, 95% CI (confidence interval) = 0.69-0.93]. However, the meta-analysis contradicted the results in Asian (OR = 1.12, 95% CI = 0.96-1.30). The same analysis was also applied in Caucasian and presented similar results from Asian (OR = 1.18, 95% CI = 0.98-1.42). The TSA showed our case-control study to be the decisive sample leading to a null association among Asian population. The high heterogeneity (I = 75%) could explain the contradictory results between the case-control study and the meta-analysis. However, further case-weighted meta-regression did not find any significant interaction between measured factors and MTHFR C677T on CKD. CONCLUSIONS: High heterogeneities were found in both Caucasian and Asian, which caused the null relationship in meta-analysis while there were significant effects in individual studies. Future studies should further explore the high heterogeneity that might be hidden in unmeasured gene-environment interactions, to explain the diverse findings among different populations.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Insuficiência Renal Crônica/genética , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença , Humanos , Masculino , Taiwan
5.
Int Heart J ; 61(3): 553-561, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32418960

RESUMO

Many published studies have evaluated the association between the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133) polymorphism and the risk of congenital heart disease (CHD); however, the specific conclusion is still controversial.To get a more accurate conclusion, we used a meta-analysis to evaluate the association between the MTHFR gene C677T polymorphism and the risk of CHD.Based on the design-based search strategy, a comprehensive literature search was conducted on PubMed, OVID, Cochrane Library, Embase, Wanfang, CNKI, and Web of Science. We selected the Newcastle-Ottawa Scale (NOS) to assess the quality of the included studies. We performed a heterogeneity test on the results of the study and calculated the combined odds ratios (ORs) and its corresponding 95% confidence intervals (95% CIs) under a random- or fixed-effect model. Subgroup analyses were conducted by ethnicity, source of controls, sample size, and genotyping method. Sensitivity analysis was used to insure authenticity of this meta-analysis result. Egger's test and Begg's funnel plot were performed to detect publication bias.Eventually, our meta-analysis included 15 eligible studies. We observed a significant correlation between the MTHFR C677T polymorphism and the development of CHD in the recessive model (OR: 1.35, 95% CI: 1.06-1.71, P = 0.006) for the overall population. In subgroups stratified by ethnicity and source of controls, subgroup analyses indicated similar associations in Asians and hospital-based groups, but not for Caucasians and population-based groups. Egger's test and Begg's funnel plot demonstrated no significant publication bias in our study.Our analysis identified that MTHFR C677T allele is a risk genetic for CHD development, especially in Asians compared with Caucasians.


Assuntos
Cardiopatias Congênitas/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Predisposição Genética para Doença , Humanos
6.
Nutr Metab Cardiovasc Dis ; 30(6): 939-947, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32404292

RESUMO

BACKGROUND AND AIMS: Elevated homocysteine concentration is associated with a higher risk of cardiovascular disease. The aim of our study was to determine the environmental and genetic factors associated with serum homocysteine concentration in healthy young adults. Moreover, we aimed to determine the cutoff value of homocysteine concentration for predicting unfavorable MTHFR genotype and to investigate whether this association is modified by dietary patterns and serum folate status. METHODS AND RESULTS: A total of 744 healthy individuals, aged 18-35 years, were included in the study. Diet quality was assessed by establishing diet quality scores and adherence to the pro-Healthy Diet Index (pHDI) and non-Healthy Diet Index (nHDI). Genotyping was performed using the TaqMan method. Multivariate analysis showed that pHDI, creatinine, folate concentrations, and the T/T genotype of the C677T polymorphism in MTHFR, as well as the interaction between the T/T genotype of MTHFR (C677T polymorphism) and folate level, were most strongly related to homocysteine concentrations. The specificity of a homocysteine >13.1 µmol/l in predicting T/T homozygous status was 76% (area under the curve 0.68). CONCLUSION: Healthy dietary patterns, folate, and creatinine levels, as well as the C677T polymorphism, proved to be the strongest predictors of homocysteine concentrations. T/T genotype of MTHFR modifies the relationship between folate and homocysteine.


Assuntos
Dieta Saudável , Comportamento Alimentar , Interação Gene-Ambiente , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , Adolescente , Adulto , Fatores Etários , Biomarcadores/sangue , Creatinina/sangue , Feminino , Ácido Fólico/sangue , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
7.
Curr Atheroscler Rep ; 22(4): 13, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32440785

RESUMO

PURPOSE OF REVIEW: Intracranial atherosclerosis (ICAS) is the most common cause of stroke throughout the world. It also increases the risk of recurrent stroke and dementia. As a complex and multifactorial disease, ICAS is influenced by multiple genetic, biological, and environmental factors. This review summarizes the candidate gene and genome-wide studies aimed at discovering genetic risk factors of ICAS. RECENT FINDINGS: Numerous studies have focused on the association between single-nucleotide polymorphisms (SNPs) of atherosclerosis-related genes and the risk of ICAS. Variants in adiponectin Q (ADIPOQ), ring finger protein 213 (RNF213), apolipoprotein E (APOE), phosphodiesterase 4D (PDE4D), methylenetetrahydrofolate reductase (MTHFR), lipoprotein lipase (LPL), α-adducin (ADD1) genes, angiotensin-converting enzyme (ACE), and other genes related to renin-angiotensin-aldosterone system have been associated with ICAS. We review the available evidences on the candidate genes and SNPs associated with genetic susceptibility to ICAS, and point out future developments of this field. Genetic discoveries could have clinical implications for intracranial atherosclerotic disease.


Assuntos
Predisposição Genética para Doença/genética , Arteriosclerose Intracraniana/genética , Adenosina Trifosfatases/genética , Adiponectina/genética , Apolipoproteínas E/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Feminino , Humanos , Lipase Lipoproteica/genética , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Peptidil Dipeptidase A/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Ubiquitina-Proteína Ligases/genética
8.
Urologiia ; (2): 66-70, 2020 Apr.
Artigo em Russo | MEDLINE | ID: mdl-32351067

RESUMO

References. Disturbances of spermogram parameters are associated with infertility in men and are determined by polymorphisms of many genes involved in spermatogenesis. Folate metabolism plays an important role in spermatogenesis, as it is involved in the synthesis, repair and methylation of DNA. OBJECTIVE: the distribution of C677T (rs1801133) and A1298C (rs1801131) polymorphisms of the MTHFR gene among infertile and fertile men in the Moscow region and to identify a possible Association of these polymorphisms with the risk of pathospermia. MATERIALS AND METHODS: the study included 127 infertile men with different forms of pathospermia and 68 fertile men (with one or more children). Genotyping of polymorphisms (C677T and A1298C) gene MTHFR was performed by real-time polymerase chain reaction (PCR-RV). RESULTS: Analysis of the distribution of MTHFR genotypes (C677T and A1298C) revealed no significant differences in the distribution of genotypes in groups of infertile and fertile men. The frequency of minor allele 1298S in asthenospermia was 52%, in teratospermia was 36% and in men with azzospermia - 33% (2=8.67; p=0.003). DISCUSSION: To date, there are no published results on the study of the Association of polymorphisms of folate-metabolizing enzyme genes with the development of pathospermia among men in the Moscow region. The results of our study demonstrate that 1298 polymorphism of the MTHFR gene may be involved in the etiology of male infertility in patients of the Moscow region. CONCLUSION: Comparative analysis of gene and genotype frequencies by the studied polymorphisms in infertile men with different forms of pathospermia showed an associative relationship of allele 1298C of MTHFR gene with the risk of asthenozoospermia (p<0.05).


Assuntos
Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Estudos de Casos e Controles , Criança , Frequência do Gene , Genótipo , Humanos , Masculino , Moscou , Polimorfismo de Nucleotídeo Único
9.
J Appl Oral Sci ; 28: e20190583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267380

RESUMO

BACKGROUND: Genetic and epigenetic changes have been associated with periodontitis in various genes; however, little is known about genes involved in epigenetic mechanisms and in oxidative stress. OBJECTIVE: This study aims to investigate the association of polymorphisms C677T in MTHFR (rs1801133) and -149C→T in DNMT3B (rs2424913), as well as the methylation profiles of MTHFR, miR-9-1, miR-9-3, SOD1, and CAT with periodontitis. The association between polymorphisms and DNA methylation profiles was also analyzed. METHODOLOGY: The population studied was composed of 100 nonsmokers of both sexes, divided into healthy and periodontitis groups. Genomic DNA was extracted from the epithelial buccal cells, which were collected through a mouthwash. Polymorphism analysis was performed through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), while methylation-specific PCR (MSP) or combined bisulfite restriction analysis techniques were applied for methylation analysis. RESULTS: For DNMT3B, the T allele and the TT genotype were detected more frequently in the periodontitis group, as well as the methylated profile on the miR-9-1 promoter region. There was also a tendency towards promoter region methylation on the CAT sequence of individuals with periodontal disease. CONCLUSION: The polymorphism -149C→T in DNMT3B (rs2424913) and the methylated profile of the miR-9-1 promoter region are associated with periodontitis.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , MicroRNAs/genética , Periodontite/genética , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , Catalase/genética , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Superóxido Dismutase-1/genética
10.
Wei Sheng Yan Jiu ; 49(1): 123-131, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32290927

RESUMO

OBJECTIVE: To analyze geographical distribution characteristics of folate metabolism related single nucleotide polymorphisms. METHODS: This work made a statistical analysis of MTHFR and MTRR gene polymorphism distribution about Chinese Han and minority childbearing age women in 16 provinces and 2 municipalities from 64 published Chinese literatures, depicted the regional distributive characteristics of the two gene polymorphisms, and analyzed the association with neural tube defects status for a long time in China. RESULTS: By summarizing and analyzing single nucleotide polymorphisms of MTHFR C677 T in Chinese Han and minority childbearing age women in 16 provinces and 2 municipalities, the results showed that MTHFR 677 TT and 677 T allele frequency increased steadily from south to north, MTHFR 1298 CC occupied a very small proportion. Through interaction analysis of A1298 C and C677 T, the result showed that two genes presented a linkage imbalance, and TT/AA frequency distribution presented a gradually decreasing trend from north to south, and there were no TT/AC, TT/CC, and CT/CC nationwide, it was found that MTRR 66 AA accounted from 34% to 58%, with the northern part slightly higher than the southern part. And MTRR 66 GG was between 5% and 17%. CONCLUSION: We could pay attention to gene polymorphism risk assessment to reduce neural tube defects for childbearing age women, in order to provide powerful human genetics data support for improving the birth population quality and national public health policy.


Assuntos
Ferredoxina-NADP Redutase/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Carbono , China , Feminino , Frequência do Gene , Genética Populacional , Genótipo , Geografia , Humanos , Redes e Vias Metabólicas
11.
Artigo em Russo | MEDLINE | ID: mdl-32323943

RESUMO

OBJECTIVE: To study the association of the C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene with the risk of schizophrenia in a large sample, including schizophrenic patients and mentally healthy people, and to investigate the relationship of this polymorphism with the severity of schizophrenia symptoms and genotype-environment interaction effects on these symptoms. MATERIAL AND METHODS: The sample for genotyping consisted of 1357 patients with schizophrenia and schizophrenia spectrum disorders and 711 people of the control group. The severity of symptoms was assessed with the PANSS. Obstetrical complications and a traumatic brain injury in medical history were studied as environmental factors. RESULTS AND CONCLUSION: No association was found between MTHFR C677T polymorphism and schizophrenia. There was no genotype effect on the severity of symptoms on the PANSS subscales. The effect of genotype-environment interactions on the severity of schizophrenia symptoms was not detected. The results do not confirm the data of a number of studies on the relationship of MTHFR C677T polymorphism with schizophrenia symptoms.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Predisposição Genética para Doença , Genótipo , Humanos , Esquizofrenia/enzimologia
12.
BMC Neurol ; 20(1): 128, 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32278343

RESUMO

BACKGROUND: Hyperhomocysteinemia (HHCY) is a risk factor for cardiovascular and cerebrovascular diseases. The C677T 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphism increases homocysteine (HCY) levels. This study analyzed the relationship between C677T MTHFR polymorphism and the therapeutic effect of lowering HCY in stroke patients with HHCY. METHODS: Baseline data were collected from stroke patients with HHCY for this prospective cohort study. The C677T MTHFR genotype was detected by polymerase chain reaction-restriction fragment length polymorphism and the therapeutic effect to reduce HCY was compared. RESULTS: Of 200 stroke patients 162 (81.0%) completed follow-up and were evaluated. Most of them responded well to treatment (103 cases, 63.5%), but 59 (36.4%) patients were in the poor efficacy group. There was a significant difference in terms of age (P < 0.001), hypertension (P = 0.041), hyperuricemia (P = 0.042), HCY after treatment (P < 0.001), and MTHFR genotype (P < 0.001) between the poor efficacy and effective groups, with increased frequency of the TT genotype in the poor efficacy group. Logistic regression showed that the T allele was associated with poor efficacy (OR = 0.733, 95%CI: 0.693, 0.862, P < 0.001). In the codominant model the TT genotype was associated with poor outcome (OR = 0.862, 95%CI: 0.767, 0.970, P = 0.017) and this was also the case in the recessive model (OR = 0.585, 95%CI: 0.462, 0.741, P < 0.001) but there was no association between CT and TT in the dominant model. CONCLUSIONS: The T allele and TT genotype of the MTHFR C677T polymorphism was associated with poor HCY reduction treatment efficacy in stroke patients with HHCY. TRIAL REGISTRATION: The registration number of the clinical trial is ChiCTR1800020048. Registration date: December 12, 2018.


Assuntos
Homocisteína/sangue , Hiper-Homocisteinemia/terapia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Acidente Vascular Cerebral/complicações , Adulto , Idoso , Alelos , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Estudos Prospectivos , Fatores de Risco
13.
Cancer Epidemiol ; 65: 101693, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32135505

RESUMO

BACKGROUND: Childhood acute lymphoblastic leukaemia (ALL) is a heterogeneous disease associated with multiple risk factors including genetic susceptibility. Polymorphisms in folate genes have been associated with a protective effect against ALL, although some studies contradict these findings. We aimed to test whether there is an association between the MTHFR rs1801133 variant and the occurrence of B-cell precursor ALL (BCP-ALL) taking in account molecularly distinct subtypes of fetal origin. METHODS: We performed a case-control genotyping study with 2067 samples, 1309 ALL and 758 controls, from children aged ≤ 15 years for MTHFR rs1801133 polymorphism. Risk associations were calculated by odds ratios estimated with unconditional logistic regression, adjusted for frequency-matched ethnic groups. RESULTS: Overall, MTHFR rs1801133 does not impact ALL risk in children with more than 6 years of age. A significant positive association for MTHFR rs1801133 variant was found for ALL with KMT2A-r in the dominant model (adj. OR, 1.48, 95 % CI, 1.01-2.17), while ETV6-RUNX1 and Hyperdiploid subgroups have shown a borderline effect (adj. OR, 1.33, 95 % CI, 0.99-1.78). CONCLUSIONS: The polymorphism MTHFR rs1801133 increased the risk of infant ALL in Brazilian population.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia
14.
Pregnancy Hypertens ; 20: 7-13, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32120336

RESUMO

BACKGROUND: Pre-eclampsia (PE) is a leading cause of maternal and neonatal mortality in Africa; and has been associated with the interplay of genetic, metabolic and environmental factors. Polymorphisms of methylene tetrahydrofolate reductase (MTHFR) and methionine synthase (MTR) folate cycle genes, have been controversially associated with pre-eclampsia in studies from different human populations. OBJECTIVES: To determine the distribution of MTHFR C677T and MTR A2756G polymorphisms in a Nigerian population and evaluate possible associations with the occurrence of pre-eclampsia and homocysteine metabolic derangement. MATERIALS AND METHODS: This study was a hospital based study carried out in Lagos, South-western Nigeria. Two hundred pregnant women clinically diagnosed with pre-eclampsia (study group) and 200 apparently healthy non-pre-eclamptic pregnant women (control group) were recruited for the study after written informed consent. Pre-eclampsia was diagnosed based on the International Society for the Study of Hypertension in Pregnancy re-classification of 2013. MTHFR C677T and MTR A2756G polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Statistical analyzes were performed using SPSS version 23. Hardy-Weinberg distribution were tested with χ2 test. Logistic regression model was used to evaluate the relationship of variables with pre-eclampsia. A value of p < 0.05 was considered statistically significant. RESULTS: MTHFR genotype frequencies of CC, CT and TT were 59.8%; 31.2% and 9.0% in study group and 76.6%; 22.3% and 1.0% in the control group respectively. MTR A2756G genotype frequencies of AA, AG and GG genotypes were 71.9%; 20.1% and 8.0% for the study group and 81.5%; 16.4% and 2.1% for the control group. Occurrence of pre-eclampsia was significantly associated with presence of T allele of MTHFR (OR = 1.855; p < 0.05) and G allele of MTR genes (OR = 1.269; p < 0.05), Homozygosity of TG haplotype significantly increased the occurrence of pre-eclampsia among Nigerian women (OR = 2.252; p < 0.05). Population attributable risk fraction percent for the T and G alleles were 16.4% and 11.5% respectively. Mean plasma Hcy level was not, however, significantly affected by MTHFR/MTR haplotypes (F = 1.54; p = 0.157). CONCLUSION: MTHFR C677T and MTR A2756G polymorphisms were associated with pre-eclampsia in a population of pregnant women in Lagos, Nigeria.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Pressão Sanguínea/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia/genética , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Heterozigoto , Homozigoto , Humanos , Nigéria , Fenótipo , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/enzimologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Fatores de Risco , Adulto Jovem
15.
Genet Test Mol Biomarkers ; 24(3): 150-155, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32119787

RESUMO

Purpose: The methylene tetrahydrofolate reductase (MTHFR) C677T, MTHFR A1298C, and the methionine synthase reductase (MTRR) A66G polymorphisms are the three most common folate metabolism-related loci in the Chinese population. They are associated with numerous birth defects or congenital diseases. To facilitate screening and genetic counseling, we established a method for the simultaneous detection of these three polymorphisms using the Luminex liquid suspension chip and multiple asymmetric polymerase chain reactions (PCRs). Materials and Methods: The three polymorphisms were amplified by multiplex PCR with biotinylated primers, followed by hybridization with six probe-linked magnetic microspheres. The mean fluorescent intensity value in each microsphere was detected by Luminex Magpix for polymorphism detection in 150 samples and confirmed by sequencing. Results: The consistency between the Luminex liquid suspension chip method and sequencing was 100%. Among the 150 randomized samples, the minor allele frequency (MAF) of MTHFR C677T was 0.41, which was the most common variant allele, followed by MTRR A66G (MAF = 0.24), and finally MTHFR A1298C (MAF = 0.19). Conclusion: The Luminex liquid suspension chip method can replace sequencing to analyze the MTHFR C677T, MTRR A1298C, and MTRR A66G loci simultaneously as a rapid, convenient, accurate, and stable method for large-scale testing.


Assuntos
Ferredoxina-NADP Redutase/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Reação em Cadeia da Polimerase/métodos , Adulto , Alelos , Grupo com Ancestrais do Continente Asiático/genética , China , Primers do DNA/genética , Feminino , Ferredoxina-NADP Redutase/análise , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Genótipo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/análise , Polimorfismo de Nucleotídeo Único/genética
16.
Vasc Health Risk Manag ; 16: 53-56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021228

RESUMO

Introduction: Factor V Leiden (G1691A), prothrombin (G20210A) and MTHFR (C677T) gene mutations were investigated in many studies for their association with Deep Venous Thrombosis. Case Presentation: A North Lebanese family has been examined, from an index case, a 40-year-old woman, who had a history of venous thrombosis with unexplained recurrent miscarriage. The index case was found to be heterozygous for factor V Leiden G1691A, prothrombin G20210A, and methylenetetrahydrofolate reductase C677T gene variants. Her family members were heterozygous for at least two of the three-point mutations, and multiple risk factors associated with thrombophilia were identified. Conclusion: Our findings emphasize the need for clarifying the utility and futility of thrombophilia testing in the era of molecular diagnostics.


Assuntos
Aborto Habitual/etiologia , Resistência à Proteína C Ativada/genética , Coagulação Sanguínea/genética , Fator V/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação , Protrombina/genética , Trombofilia/genética , Trombose Venosa/etiologia , Aborto Habitual/sangue , Aborto Habitual/diagnóstico , Resistência à Proteína C Ativada/sangue , Resistência à Proteína C Ativada/complicações , Resistência à Proteína C Ativada/diagnóstico , Adulto , Feminino , Predisposição Genética para Doença , Hereditariedade , Humanos , Líbano , Linhagem , Fenótipo , Gravidez , Fatores de Risco , Trombofilia/sangue , Trombofilia/complicações , Trombofilia/diagnóstico , Trombose Venosa/sangue , Trombose Venosa/diagnóstico
17.
Adv Clin Exp Med ; 29(2): 251-256, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32073761

RESUMO

BACKGROUND: Down syndrome (DS) is the most frequent cause of intellectual disability. In 95% of cases, it is caused by simple trisomy of chromosome 21 resulting from nondisjunction of chromosomes in meiotic division. Currently, the molecular and cellular mechanisms responsible for the phenomenon of nondisjunction are unknown. OBJECTIVES: To investigate the incidence of 5 single-nucleotide polymorphisms (SNPs) of the MTHFR gene in a population of Polish mothers who had given birth to children with trisomy 21 in comparison with a control group of women with healthy offspring. MATERIAL AND METHODS: The test material comprised venous blood collected from mothers who had given birth to a child with DS (study group, n = 130) as well as from women who had given birth to children without trisomy 21 (control group, n = 88). DNA was isolated using a kit manufactured by Qiagen. Amplification was carried out using a Qiagen Multiplex PCR Kit (Qiagen); genotyping was performed using SNaPshot Genotyping MasterMix (Applied Biosystems). RESULTS: No statistically significant differences were observed in the frequency of genotypes between the examined groups in terms of the polymorphisms of the MTHFR gene. CONCLUSIONS: In the Polish population studied, no relationship was found between the occurrence of particular genotypes of the MTHFR gene, i.e., 677CT, 1298AC, rs3737964, rs4846048, and rs1994798, in women and the birth of children with trisomy 21. The results contradict the validity of research on polymorphisms of the MTHFR gene as potential predisposing factors for the occurrence of trisomy 21 in children.


Assuntos
Síndrome de Down , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mães , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Criança , Feminino , Genótipo , Humanos , Polônia , Gravidez , Fatores de Risco
18.
Nutrients ; 12(2)2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32019154

RESUMO

Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism associated with body fat accumulation could possibly trigger an inflammatory process by elevating homocysteine levels and increasing cytokine production, causing several diseases. This study aimed to evaluate the effects of food intervention, and not folate supplements, on the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) in overweight and obese women with the MTHFR C677T polymorphism. A randomized, double-blind eight-week clinical trial of 48 overweight and obese women was conducted. Participants were randomly assigned into two groups. They received 300 g of vegetables daily for eight weeks containing different doses of folate: 95 µg/day for Group 1 and 191 µg/day for Group 2. MTHFR C677T polymorphism genotyping was assessed by digestion with HinfI enzyme and on 12% polyacrylamide gels. Anthropometric measurements, 24-h dietary recall, and biochemical analysis (blood folic acid, vitamin B12, homocysteine (Hcy), TNF-α, IL-1ß, and IL-6) were determined at the beginning and end of the study. Group 2 had a significant increase in folate intake (p < 0.001) and plasma folic acid (p < 0.05) for individuals with the cytosine-cytosine (CC), cytosine-thymine (CT), and thymine-thymine (TT) genotypes. However, only individuals with the TT genotype presented reduced levels of Hcy, TNF-α, IL-6, and IL-1ß (p < 0.001). Group 1 showed significant differences in folate consumption (p < 0.001) and folic acid levels (p < 0.05) for individuals with the CT and TT genotypes. Food intervention with folate from vegetables increased folic acid levels and reduced interleukins, TNF-α, and Hcy levels, mainly for individuals with the TT genotype.


Assuntos
Ácido Fólico/administração & dosagem , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Obesidade/genética , Sobrepeso/genética , Verduras , Adulto , Dieta/métodos , Inquéritos sobre Dietas , Método Duplo-Cego , Feminino , Ácido Fólico/sangue , Genótipo , Homocisteína/sangue , Humanos , Interleucina-1beta/sangue , Interleucina-6/sangue , Pessoa de Meia-Idade , Nutrigenômica , Obesidade/sangue , Obesidade/dietoterapia , Sobrepeso/sangue , Sobrepeso/dietoterapia , Polimorfismo Genético , Fator de Necrose Tumoral alfa/sangue , Vitamina B 12/sangue
19.
Mutat Res ; 819-820: 111687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31968288

RESUMO

Methylene tetrahydrofolate reductase (MTHFR) is a flavoprotein, involved in one-carbon pathway and is responsible for folate and homocysteine metabolism. Regulation of MTHFR is pivotal for maintaining the cellular concentrations of methionine and SAM (S-adenosyl methionine) which are essential for the synthesis of nucleotides and amino acids, respectively. Therefore, mutations in MTHFR leads to its dysfunction resulting in conditions like homocystinuria, cardiovascular diseases, and neural tube defects in infants. Among these conditions, homocystinuria has been highly explored, as it manifests ocular disorders, cognitive disorders and skeletal abnormalities. Hence, in this study, we intend to explore the mutational landscape of human MTHFR isoform-1 (h.MTHFR-1) to decipher the most pathogenic variants pertaining to homocystinuria. Thus, a multilevel stringent prioritization of non-synonymous mutations in h.MTHFR-1 by integrative machine learning approaches was implemented to delineate highly deleterious variants based on its pathogenicity, impact on structural stability and functionality. Subsequently, extended molecular dynamics simulations and molecular docking studies were also integrated in order to prioritize the mutations that perturbs structural stability and functionality of h.MTHFR-1. In addition, displacement of Loop (Arg157-Tyr174) and helix α9 (His263-Ser272) involved in open/closed conformation of substrate binding domain were also probed to confirm the functional loss. On juxtaposed analysis, it was inferred that among 126 missense mutations screened, along with known pathogenic mutations (H127 T, A222 V, T227 M, F257 V and G387D) predicted that W500C, P254S and D585 N variants could be potentially driving homocystinuria. Thus, uncovering the prospects for inclusion of these mutations in diagnostic panels based on further experimental validations.


Assuntos
Homocistinúria/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/química , Mutação de Sentido Incorreto , S-Adenosilmetionina/química , Tetra-Hidrofolatos/química , Sítio Alostérico , Motivos de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Expressão Gênica , Homocistinúria/enzimologia , Homocistinúria/patologia , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Aprendizado de Máquina , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , NADP/química , NADP/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , S-Adenosilmetionina/metabolismo , Especificidade por Substrato , Tetra-Hidrofolatos/metabolismo , Termodinâmica
20.
Medicine (Baltimore) ; 99(4): e18720, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977861

RESUMO

The methylenetetrahydrofolate reductase (MTHFR) may play a pathological role in polycystic ovary syndrome (PCOS). However, the conclusions of published reports on the relationship between the MTHFR C677T polymorphism and PCOS risk remain controversial.To derive a more precise estimation we performed a metaanalysis based on 22 studies that together included 2405 cases and 2419 controls. PubMed, EMBASE, WanFang and the Chinese National Knowledge Infrastructure databases were used to retrieve articles up to up to October 28, 2019. The crude odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated to evaluate the association.Metaanalysis results showed a significant association between the MTHFR C677T polymorphism and PCOS risk in 3 genetic models (allele model: OR = 1.40, 95% CI = 1.27-1.53; dominant model: OR = 1.47, 95% CI = 1.17-1.85); homozygous model: OR = 1.90, 95% CI = 1.55-2.32). Moreover, significant associations were observed when stratified by ethnicity, source of controls, etiology, and genotype methods.This metaanalysis suggests that the T-allele of the MTHFR C677T polymorphism is associated with an increased risk of PCOS, especially in Asians further studies with larger population sizes are needed to confirm these results.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Síndrome do Ovário Policístico/genética , Grupos de Populações Continentais , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
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