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Sample records for mthfr gene predisposes

  1. [Relationship of MTHFR gene polymorphisms with infertility].

    PubMed

    Guo, Kai-min; Tian, Run-hui; Wang, Hong-liang

    2016-02-01

    The folate metabolic pathway plays important roles in cellular physiology by participating in nucleotide synthesis, DNA repair and methylation, and maintenance and stability of the genome. Methylenetetrahydrofolate reductase (MTHFR) is a key regulatory enzyme involved in folate metabolism. Polymorphisms of MTHFR may change the level of homocysteine and affect DNA synthesis and methylation, leading to an increased oxidative stress and disturbed methylation reactions and consequently affecting reproductive function. This article presents an overview on MTHFR gene polymorphisms, proposing that multicentered, large-sample and long-term prospective studies are needed to reveal the relationship between MTHFR gene polymorphisms and infertility. PMID:26939404

  2. MTHFR gene polymorphisms in bladder cancer in the Turkish population.

    PubMed

    Izmirli, Muzeyyen; Inandiklioglu, Nihal; Abat, Deniz; Alptekin, Davut; Demirhan, Osman; Tansug, Zuhtu; Bayazit, Yildirim

    2011-01-01

    Bladder cancer is the 9th most common cancer and is responsible for malignancy related death all on the world. Folate and folate related enzyme polymorphisms related to the cancer risk. The methylene tethrahydrofolate reductase (MTHFR) enzyme is folate related and association of bladder cancer and MTHFR gene. Our purpose was to assess the prevalence of MTHFR gene 677 CT and 1298 AC polymorphisms and Bladder cancer in Turkey. We intended that bladder cancer patients and controls and we used the Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) methods. The MTHFR gene C677T and A1298C polymorphisms were associated with an increased risk of bladder cancer in our population (For the MTHFR gene C677T polymorphism and A1298C polymorphism; p=0.036<0.05; p=0.278>0.05 respectively). Consequently, the MTHFR gene C677T polymorphism augments the risk of bladder cancer in Turkey. PMID:22126575

  3. Relationship of MTHFR gene polymorphisms with renal and cardiac disease

    PubMed Central

    Trovato, Francesca M; Catalano, Daniela; Ragusa, Angela; Martines, G Fabio; Pirri, Clara; Buccheri, Maria Antonietta; Di Nora, Concetta; Trovato, Guglielmo M

    2015-01-01

    AIM: To investigate the effects of different methylenetetrahydrofolate reductase (MTHFR) 677C>T gene polymorphism and hyperhomocysteinemia for the development of renal failure and cardiovascular events, which are controversial. METHODS: We challenged the relationship, if any, of MTHFR 677C>T and MTHFR 1298A>C polymorphisms with renal and heart function. The present article is a reappraisal of these concepts, investigating within a larger population, and including a subgroup of dialysis patients, if the two most common MTHFR polymorphisms, C677T and A1298C, as homozygous, heterozygous or with a compound heterozygous state, show different association with chronic renal failure requiring hemodialysis. MTHFR polymorphism could be a favorable evolutionary factor, i.e., a protective factor for many ominous conditions, like cancer and renal failure. A similar finding was reported in fatty liver disease in which it is suggested that MTHFR polymorphisms could have maintained and maintain their persistence by an heterozygosis advantage mechanism. We studied a total of 630 Italian Caucasian subject aged 54.60 ± 16.35 years, addressing to the increased hazard of hemodialysis, if any, according to the studied MTHFR genetic polymorphisms. RESULTS: A favorable association with normal renal function of MTHFR polymorphisms, and notably of MTHFR C677T is present independently of the negative effects of left ventricular hypertrophy, increased Intra-Renal arterial Resistance and hyperparathyroidism. CONCLUSION: MTHFR gene polymorphisms could have a protective role on renal function as suggested by their lower frequency among our dialysis patients in end-stage renal failure; differently, the association with left ventricular hypertrophy and reduced left ventricular relaxation suggest some type of indirect, or concurrent mechanism. PMID:25664255

  4. MTHFR Gene C677T Polymorphism in Autism Spectrum Disorders.

    PubMed

    Sener, Elif Funda; Oztop, Didem Behice; Ozkul, Yusuf

    2014-01-01

    Aim. Autism is a subgroup of autism spectrum disorders, classified as a heterogeneous neurodevelopmental disorder and symptoms occur in the first three years of life. The etiology of autism is largely unknown, but it has been accepted that genetic and environmental factors may both be responsible for the disease. Recent studies have revealed that the genes involved in the folate/homocysteine pathway may be risk factors for autistic children. In particular, C677T polymorphism in the MTHFR gene as a possible risk factor for autism is still controversial. We aimed to investigate the possible effect of C677T polymorphism in a Turkish cohort. Methods. Autism patients were diagnosed by child psychiatrists according to DSM-IV and DSM-V criteria. A total of 98 children diagnosed as autistic and 70 age and sex-matched children who are nonautistic were tested for C677T polymorphism. This polymorphism was studied by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Results. MTHFR 677T-allele frequency was found to be higher in autistic children compared with nonautistic children (29% versus 24%), but it was not found statistically significant. Conclusions. We conclude that other MTHFR polymorphisms such as A1298C or other folate/homocysteine pathway genes may be studied to show their possible role in autism. PMID:25431675

  5. MTHFR Gene C677T Polymorphism in Autism Spectrum Disorders

    PubMed Central

    Oztop, Didem Behice; Ozkul, Yusuf

    2014-01-01

    Aim. Autism is a subgroup of autism spectrum disorders, classified as a heterogeneous neurodevelopmental disorder and symptoms occur in the first three years of life. The etiology of autism is largely unknown, but it has been accepted that genetic and environmental factors may both be responsible for the disease. Recent studies have revealed that the genes involved in the folate/homocysteine pathway may be risk factors for autistic children. In particular, C677T polymorphism in the MTHFR gene as a possible risk factor for autism is still controversial. We aimed to investigate the possible effect of C677T polymorphism in a Turkish cohort. Methods. Autism patients were diagnosed by child psychiatrists according to DSM-IV and DSM-V criteria. A total of 98 children diagnosed as autistic and 70 age and sex-matched children who are nonautistic were tested for C677T polymorphism. This polymorphism was studied by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Results. MTHFR 677T-allele frequency was found to be higher in autistic children compared with nonautistic children (29% versus 24%), but it was not found statistically significant. Conclusions. We conclude that other MTHFR polymorphisms such as A1298C or other folate/homocysteine pathway genes may be studied to show their possible role in autism. PMID:25431675

  6. Association of MTHFR gene polymorphisms with breast cancer survival

    PubMed Central

    Martin, Damali N; Boersma, Brenda J; Howe, Tiffany M; Goodman, Julie E; Mechanic, Leah E; Chanock, Stephen J; Ambs, Stefan

    2006-01-01

    Background Two functional single nucleotide polymorphisms (SNPs) in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, C677T and A1298C, lead to decreased enzyme activity and affect chemosensitivity of tumor cells. We investigated whether these MTHFR SNPs were associated with breast cancer survival in African-American and Caucasian women. Methods African-American (n = 143) and Caucasian (n = 105) women, who had incident breast cancer with surgery, were recruited between 1993 and 2003 from the greater Baltimore area, Maryland, USA. Kaplan-Meier survival and multivariate Cox proportional hazards regression analyses were used to examine the relationship between MTHFR SNPs and disease-specific survival. Results We observed opposite effects of the MTHFR polymorphisms A1298C and C677T on breast cancer survival. Carriers of the variant allele at codon 1298 (A/C or C/C) had reduced survival when compared to homozygous carriers of the common A allele [Hazard ratio (HR) = 2.05; 95% confidence interval (CI), 1.05–4.00]. In contrast, breast cancer patients with the variant allele at codon 677 (C/T or T/T) had improved survival, albeit not statistically significant, when compared to individuals with the common C/C genotype (HR = 0.65; 95% CI, 0.31–1.35). The effects were stronger in patients with estrogen receptor-negative tumors (HR = 2.70; 95% CI, 1.17–6.23 for A/C or C/C versus A/A at codon 1298; HR = 0.36; 95% CI, 0.12–1.04 for C/T or T/T versus C/C at codon 677). Interactions between the two MTHFR genotypes and race/ethnicity on breast cancer survival were also observed (A1298C, pinteraction = 0.088; C677T, pinteraction = 0.026). Conclusion We found that the MTHFR SNPs, C677T and A1298C, were associated with breast cancer survival. The variant alleles had opposite effects on disease outcome in the study population. Race/ethnicity modified the association between the two SNPs and breast cancer survival. PMID:17069650

  7. Gene variants predisposing to SIDS: current knowledge.

    PubMed

    Opdal, Siri H; Rognum, Torleiv O

    2011-03-01

    Genetic risk factors play a role in sudden unexpected infant death; either as a cause of death, such as in cases with medium-chain acyl-coenzyme A dehydrogenase deficiency and cardiac arrest due to long QT syndrome, or as predisposing factors for sudden infant death syndrome (SIDS). Most likely genetic predisposition to SIDS represent a polygenic inheritance pattern leading to sudden death when combined with other risk factors, such as a vulnerable developmental stage of the central nervous system and/or the immune system, in addition to environmental risk factors, such as a common cold or prone sleeping position. Genes involved in the regulation of the immune system, cardiac function, the serotonergic network and brain function and development have so far emerged as the most important with respect to SIDS. The purpose of the present paper is to survey current knowledge on SIDS and possible genetic contributions. PMID:20623341

  8. Methylene tetrahydrofolate reductase (MTHFR) gene polymorphisms in chronic myeloid leukemia: an Egyptian study.

    PubMed

    Khorshied, Mervat Mamdooh; Shaheen, Iman Abdel Mohsen; Abu Khalil, Reham E; Sheir, Rania Elsayed

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) gene plays a pivotal role in folate metabolism. Several genetic variations in MTHFR gene as MTHFR-C677T and MTHFR-A1298C result in decreased MTHFR activity, which could influence efficient DNA methylation and explain susceptibility to different cancers. The etiology of chronic myeloid leukemia (CML) is obscure and little is known about individual's susceptibility to CML. In order to assess the influence of these genetic polymorphisms on the susceptibility to CML and its effect on the course of the disease among Egyptians, we performed an age-gender-ethnic matched case-control study. The study included 97 CML patients and 130 healthy controls. Genotyping of MTHFR-C677T and -A1298C was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The results showed no statistical difference in the distribution of MTHFR-C677T and -A1298C polymorphic genotypes between CML patients and controls. The frequency of MTHFR 677-TT homozygous variant was significantly higher in patients with accelerated/blastic transformation phase when compared to those in the chronic phase of the disease. In conclusion, our study revealed that MTHFR-C677T and -A1298C polymorphisms could not be considered as genetic risk factors for CML in Egyptians. However, MTHFR 677-TT homozygous variant might be considered as a molecular predictor for disease progression. PMID:24338216

  9. Genomic scan for genes predisposing to schizophrenia

    SciTech Connect

    Coon, H.; Jensen. S.; Holik, J.

    1994-03-15

    We initiated a genome-wide search for genes predisposing to schizophrenia by ascertaining 9 families, each containing three to five cases of schizophrenia. The 9 pedigrees were initially genotyped with 329 polymorphic DNA loci distributed throughout the genome. Assuming either autosomal dominant or recessive inheritance, 254 DNA loci yielded lod scores less than -2.0 at {theta} = 0.0, 101 DNA markers gave lod scores less than -2.0 at {theta} = 0.05, while 5 DNA loci produced maximum lod scores greater than 1: D4S35, D14S17, D15S1, D22S84, and D22S55. Of the DNA markers yielding lod scores greater than 1, D4S35 and D22S55 also were suggestive of linkage when the Affected-Pedigree-Member method was used. The families were then genotyped with four highly polymorphic simple sequence repeat markers; possible linkage diminished with DNA markers mapping nearby D4S35, while suggestive evidence of linkage remained with loci in the region of D22S55. Although follow-up investigation of these chromosomal regions may be warranted, our linkage results should be viewed as preliminary observations, as 35 unaffected persons are not past the age of risk. 90 refs., 3 tabs.

  10. Mthfr gene ablation enhances susceptibility to arsenic prenatal toxicity

    PubMed Central

    Wlodarczyk, Bogdan J.; Zhu, Huiping; Finnell, Richard H.

    2014-01-01

    Background In utero exposure to arsenic is known to adversely affect reproductive outcomes. Evidence of arsenic teratogenicity vary widely and depend on individual genotypic differences in sensitivity to As. In this study, we investigated the potential interaction between 5,10-methylenetetrahydrofolate reductase (Mthfr) genotype and arsenic embryotoxicity using the Mthfr knockout mouse model. Methods Pregnant dams were treated with sodium arsenate, and reproductive outcomes including: implantation, resorption, congenital malformation and fetal birth weight were recorded at E18.5. Results When the dams in Mthfr+/? x Mthfr+/? matings were treated with 7.2mg/kg As, the resorption rate increased to 43.4%, from a background frequency of 7.2%. The As treatment also induced external malformations (40.9%) and significantly lowered the average fetal birth weight among fetuses, without any obvious toxic effect on the dam. When comparing the pregnancy outcomes resulting from different mating scenarios (Mthfr+/+ x Mthfr+/?, Mthfr+/? x Mthfr+/? and Mthfr?/? x Mthfr+/?) and arsenic exposure; the resorption rate showed a linear relationship with the number of null alleles (0, 1 or 2) in the Mthfr dams. Fetuses from nullizygous dams had the highest rate of external malformations (43%) and lowest average birth weight. When comparing the outcomes of reciprocal matings (nullizygote x wild-type versus wild-type x nullizygote) after As treatment, the null dams showed significantly higher rates of resorptions and malformations, along with lower fetal birth weights. Conclusions Maternal genotype contributes to the sensitivity of As embryotoxicity in the Mthfr mouse model. The fetal genotype, however, does not appear to affect the reproductive outcome after in utero As exposure. PMID:24384392

  11. Mthfr gene ablation enhances susceptibility to arsenic prenatal toxicity

    SciTech Connect

    Wlodarczyk, Bogdan J. Zhu, Huiping; Finnell, Richard H.

    2014-02-15

    Background: In utero exposure to arsenic is known to adversely affect reproductive outcomes. Evidence of arsenic teratogenicity varies widely and depends on individual genotypic differences in sensitivity to As. In this study, we investigated the potential interaction between 5,10-methylenetetrahydrofolate reductase (Mthfr) genotype and arsenic embryotoxicity using the Mthfr knockout mouse model. Methods: Pregnant dams were treated with sodium arsenate, and reproductive outcomes including: implantation, resorption, congenital malformation and fetal birth weight were recorded at E18.5. Results: When the dams in Mthfr{sup +/−} × Mthfr{sup +/−} matings were treated with 7.2 mg/kg As, the resorption rate increased to 43.4%, from a background frequency of 7.2%. The As treatment also induced external malformations (40.9%) and significantly lowered the average fetal birth weight among fetuses, without any obvious toxic effect on the dam. When comparing the pregnancy outcomes resulting from different mating scenarios (Mthfr{sup +/+} × Mthfr{sup +/−}, Mthfr{sup +/−} × Mthfr{sup +/−} and Mthfr{sup −/−} × {sup Mthfr+/−}) and arsenic exposure; the resorption rate showed a linear relationship with the number of null alleles (0, 1 or 2) in the Mthfr dams. Fetuses from nullizygous dams had the highest rate of external malformations (43%) and lowest average birth weight. When comparing the outcomes of reciprocal matings (nullizygote × wild-type versus wild-type × nullizygote) after As treatment, the null dams showed significantly higher rates of resorptions and malformations, along with lower fetal birth weights. Conclusions: Maternal genotype contributes to the sensitivity of As embryotoxicity in the Mthfr mouse model. The fetal genotype, however, does not appear to affect the reproductive outcome after in utero As exposure. - Highlights: • An interaction between Mthfr genotype and arsenic embryotoxicity is presented. • Maternal Mthfr genotype contributes to the sensitivity of As embryotoxicity. • Fetal Mthfr genotype does not affect the reproductive outcome after As exposure.

  12. Genetic and epigenetic variants in the MTHFR gene are not associated with non-Hodgkin lymphoma

    PubMed Central

    Bradshaw, Gabrielle; Sutherland, Heidi G.; Camilleri, Emily T.; Lea, Rodney A.; Haupt, Larisa M.; Griffiths, Lyn R.

    2015-01-01

    The methylenetetrahydrofolate reductase (MTHFR) gene codes for the MTHFR enzyme which plays a key role in the pathway of folate and methionine metabolism. Polymorphisms of genes in this pathway affect its regulation and have been linked to lymphoma. In this study we examined whether we could detect an association between two common non-synonymous MTHFR polymorphisms, 677C > T (rs1801133) and 1298A > C (rs1801131), and susceptibility to non-Hodgkin lymphoma (NHL) in an Australian case–control cohort. We found no significant differences between genotype or allele frequencies for either polymorphisms between lymphoma cases and controls. We also explored whether epigenetic modification of MTHFR, specifically DNA methylation of a CpG island in the MTHFR promoter region, is associated with NHL using blood samples from patients. No difference in methylation levels was detected between the case and control samples suggesting that although hypermethylation of MTHFR has been reported in tumour tissues, particularly in the diffuse large B-cell lymphoma subtype of NHL, methylation of this MTHFR promoter CpG island is not a suitable epigenetic biomarker for NHL diagnosis or prognosis in peripheral blood samples. Further studies into epigenetic variants could focus on genes that are robustly associated with NHL susceptibility. PMID:26629414

  13. Genetic and epigenetic variants in the MTHFR gene are not associated with non-Hodgkin lymphoma.

    PubMed

    Bradshaw, Gabrielle; Sutherland, Heidi G; Camilleri, Emily T; Lea, Rodney A; Haupt, Larisa M; Griffiths, Lyn R

    2015-12-01

    The methylenetetrahydrofolate reductase (MTHFR) gene codes for the MTHFR enzyme which plays a key role in the pathway of folate and methionine metabolism. Polymorphisms of genes in this pathway affect its regulation and have been linked to lymphoma. In this study we examined whether we could detect an association between two common non-synonymous MTHFR polymorphisms, 677C > T (rs1801133) and 1298A > C (rs1801131), and susceptibility to non-Hodgkin lymphoma (NHL) in an Australian case-control cohort. We found no significant differences between genotype or allele frequencies for either polymorphisms between lymphoma cases and controls. We also explored whether epigenetic modification of MTHFR, specifically DNA methylation of a CpG island in the MTHFR promoter region, is associated with NHL using blood samples from patients. No difference in methylation levels was detected between the case and control samples suggesting that although hypermethylation of MTHFR has been reported in tumour tissues, particularly in the diffuse large B-cell lymphoma subtype of NHL, methylation of this MTHFR promoter CpG island is not a suitable epigenetic biomarker for NHL diagnosis or prognosis in peripheral blood samples. Further studies into epigenetic variants could focus on genes that are robustly associated with NHL susceptibility. PMID:26629414

  14. [Polymorphism of the methylenetetrahydrofolate reductase gene (MTHFR) and incidence of hyperhomocysteinemia-related diseases].

    PubMed

    Pawlak, A L; Strauss, E

    2001-01-01

    Methylenetetrahydrofolate reductase (MTHFR), is a cytosolic enzyme, the product of which is N5-metyltetrahydrofolate, the main form of folates in tissues and the carbon donor for methylation of homocysteine to methionine. In MTHFR gene a series of the pathogenic mutations is known which lead to loss of enzymatic activity as well as the two polymorphic alleles (MTHFR 677T and 1298C) with products displaying the lowered enzyme activity resulting in hyperhomocysteinaemia. These polymorphic alleles of MTHFR represent the main genetic factor contributing to hyperhomocysteinaemia. The better known allele MTHFR 677T is found in different populations with frequency between ca. 0.1 and 0.36. In persons inheriting the variant alleles of MTHFR the increase in the level of homocysteine is noted resulting in the increased susceptibility to vascular diseases and the neural tube defects in the progeny. The procedure recommended for the prevention of effects of deficiency of MTHFR activity consists of the supplementation of the diet with 0.4 mg of folic acid daily. PMID:11468972

  15. MTHFR Gene Mutations: A Potential Marker of Late-Onset Alzheimer's Disease?

    PubMed

    Román, Gustavo C

    2015-01-01

    Recent epigenome-wide association studies have confirmed the importance of epigenetic effects mediated by DNA methylation in late-onset Alzheimer's disease (LOAD). Metabolic folate pathways and methyl donor reactions facilitated by B-group vitamins may be critical in the pathogenesis of LOAD. Methylenetetrahydrofolate reductase (MTHFR) gene mutations were studied in consecutive Alzheimer's Disease & Memory Clinic patients up to December 2014. DNA analyses of MTHFR-C667T and - A1298C homozygous and heterozygous polymorphisms in 93 consecutive elderly patients revealed high prevalence of MTHFR mutations (92.5%). Findings require confirmation in a larger series, but MTHFR mutations may become a LOAD marker, opening novel possibilities for prevention and treatment. PMID:26401555

  16. Is methylenetetrahydrofolate reductase (MTHFR) gene A1298C polymorphism related with varicocele risk?

    PubMed

    Ucar, V B; Nami, B; Acar, H; Kilinç, M

    2015-02-01

    Varicocele is one of the main reasons for male infertility the exact aetiology of which remains unclear. Methylenetetrahydrofolate reductase (MTHFR) is important for DNA synthesis and methylation, which has a key role during spermatogenesis. Numerous literature suggests that the MTHFR polymorphism may be genetic risk factors for male infertility. In this study, we evaluated C677T and A1298C MTHFR gene polymorphism frequency in patients with varicocele and normal men. A total of 107 varicocele patients and 109 fertile healthy individuals were included. Genotyping of the MTHFR gene in C677T and A1298C base pairs carried out by using real-time PCR technique and afterwards, the statistical analysis accomplished. There is a statistical difference for the frequency of 1298AA genotype in patients with varicocele compared with normal controls (P = 0.0051, OR = 2.2750). Instead, subsequently, 1298/A allel frequency in patient group was significantly higher in comparison with control group (P = 0.0174). According to our results, 1298AA genotype in MTHFR gene raises the risk of varicocele approximately 2.3 times more compared with men carrying other genotypes. The results show that genetic factors have an important role in the molecular basis of varicocele. PMID:24456105

  17. Isolated renal vein thrombosis associated with MTHFR-1298 and PAI-1 4G gene mutations.

    PubMed

    Cinemre, Hakan; Bilir, Cemil; Akdemir, Nermin

    2010-12-01

    Isolated renal vein thrombosis is very rare without the presence of nephrotic syndrome. It is more common in the newborns and infants. Whereas major risk factors in adults are the procoagulant states such as protein C or S deficiency, factor V Leiden mutation, primary or secondary antiphospholipid syndrome, severe hypothyroidism, and trauma. Here, we report a case of isolated renal vein thrombosis associated with MTHFR-1298 and PAI-1 4G gene mutations. It should be noted that the presence of MTHFR-1298 and PAI-1 4G gene mutations together might be one of the examples of genetic mutation combinations that increase the likelihood of a thrombotic event. PMID:19825918

  18. Bilateral transverse sinus thrombosis secondary to a homozygous C677T MTHFR gene mutation.

    PubMed

    Kanaan, Ziad M; Mahfouz, Rami; Taher, Ali; Sawaya, Raja A

    2008-09-01

    We describe the case of a previously healthy young man who presented with headache, diplopia, nausea, vomiting, and bilateral papilledema. Magnetic resonance venography of the brain revealed thrombosis of the right transverse sinus. Blood tests showed elevated homocysteine levels, and coagulation studies revealed a homozygous C677T mutation and a heterozygous A1298C mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. The patient had no other etiology for venous thrombosis. We recommend screening patients who present with sinus thrombosis for MTHFR gene mutations. PMID:18666857

  19. Population- and family-based studies associate the MTHFR gene with idiopathic autism in simplex families.

    PubMed

    Liu, Xudong; Solehdin, Fatima; Cohen, Ira L; Gonzalez, Maripaz G; Jenkins, Edmund C; Lewis, M E Suzanne; Holden, Jeanette J A

    2011-07-01

    Two methylenetetrahydrofolate reductase gene (MTHFR) functional polymorphisms were studied in 205 North American simplex (SPX) and 307 multiplex (MPX) families having one or more children with an autism spectrum disorder. Case-control comparisons revealed a significantly higher frequency of the low-activity 677T allele, higher prevalence of the 677TT genotype and higher frequencies of the 677T-1298A haplotype and double homozygous 677TT/1298AA genotype in affected individuals relative to controls. Family-based association testing demonstrated significant preferential transmission of the 677T and 1298A alleles and the 677T-1298A haplotype to affected offspring. The results were not replicated in MPX families. The results associate the MTHFR gene with autism in SPX families only, suggesting that reduced MTHFR activity is a risk factor for autism in these families. PMID:21069446

  20. Deep Sequencing Study of the MTHFR Gene to Identify Variants Associated with Myelomeningocele

    PubMed Central

    Aneji, Chiamaka U; Northrup, Hope; Au, Kit Sing

    2012-01-01

    INTRODUCTION Neural tube defects (NTDs) are congenital anomalies caused by a combination of genetic and environmental influences. A defect below the head region resulting in protuberance of meninges and nervous tissue is termed myelomeningocele (MM). MM, the most common NTD compatible with survival, occurs in approximately 1 in 1,000 births worldwide. Maternal pre- and periconceptional folate supplementation reduces the risk of NTDs by up to 70%. A key enzyme in folate metabolism is 5, 10-methylene-tetrahydrofolate reductase (MTHFR). OBJECTIVES Sequence the 12 exons of the MTHFR gene among 96 subjects with MM to identify variants potentially contributing to the disease trait. METHODS Exons were amplified by polymerase chain reaction and the products were sequenced by Sanger method to reveal sequence variants compared to MTHFR reference sequences. Association of variants was examined by Fisher’s test. RESULTS A novel variant c.171+3G>T was identified in intron 1 in one affected subject. The variant was not found in the subject’s unaffected mother’s DNA and the unaffected father’s DNA was unavailable. We found significant differences in allele frequencies for seven SNPs in MM subjects compared to ethnically matched reference populations reported in the single nucleotide polymorphism (SNP) database (dbSNP). CONCLUSION We identified a novel variant c.171+3G>T in the MTHFR gene that potentially affects splicing in an affected subject. Also, we observed five SNPs (rs13306561, rs2274976, rs2066462, rs12121543, and rs1476413) in the MTHFR gene not previously shown to associate with MM. The current study provides additional evidence that multiple variations in the MTHFR gene are associated with MM. PMID:22241680

  1. A COMMON POLYMORPHISM IN THE METHYLENETETRAHYDROFOLATE REDUCTASE (MTHFR) GENE IS ASSOCIATED WITH QUANTITATIVE ULTRASOUND IN THOSE WITH LOW PLASMA FOLATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study of a polymorphism in the MTHFR gene, plasma folate, and bone phenotypes in 1632 individuals revealed that the genotype effect on BMD and quantitative ultrasound was dependent on the level of folate. Our findings support the hypothesis that the association between an MTHFR polymorphism and bo...

  2. Variants in MTHFR gene and neural tube defects susceptibility in China.

    PubMed

    Wang, Yongxin; Liu, Yuan; Ji, Wenyu; Qin, Hu; Wu, Hao; Xu, Danshu; Turtuohut, Tukebai; Wang, Zengliang

    2015-08-01

    Neural tube defect (NTD) is a severe congenital birth abnormalities involving incomplete neural tube closure. 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene plays key role in folate cycle and methylation cycle, which could affect the DNA synthesis, repair and methylation. In this study, we aim to investigate the correlation between MTHFR polymorphisms and NTD-affected pregnancy. There were 444 participants involved in our study. Tag-SNPs were identified in HapMap Databases. Blood samples were collected from all subjects to further extract the genomic DNAs by TaqMan Blood DNA kits. We also carried out a meta-analysis based on previous published studies to further examine the association between MTHFR polymorphisms and NTD. In case-control study analysis, two SNPs were identified to be associated with NTD risk. The 677 C > T genetic variant was correlated with increased risk of NTD-affected pregnancy. However, the 1298 A > C polymorphism was shown to lower the risk of NTD-affected pregnancy. The protective role of 1298 A > C polymorphisms was further supported by the result of meta-analysis. Our study revealed that the SNPs of 677C > T and 1298A > C in MTHFR were associated with NTD-affected pregnancy, in which 677C > T was a risk factor and in contrast 1298A > C was protective factor against NTD. Our results of meta-analysis also revealed the 1298A > C MTHFR polymorphism play protective role in NTD. PMID:25855017

  3. Population- and Family-Based Studies Associate the "MTHFR" Gene with Idiopathic Autism in Simplex Families

    ERIC Educational Resources Information Center

    Liu, Xudong; Solehdin, Fatima; Cohen, Ira L.; Gonzalez, Maripaz G.; Jenkins, Edmund C.; Lewis, M. E. Suzanne; Holden, Jeanette J. A.

    2011-01-01

    Two methylenetetrahydrofolate reductase gene ("MTHFR") functional polymorphisms were studied in 205 North American simplex (SPX) and 307 multiplex (MPX) families having one or more children with an autism spectrum disorder. Case-control comparisons revealed a significantly higher frequency of the low-activity 677T allele, higher prevalence of the…

  4. Population- and Family-Based Studies Associate the "MTHFR" Gene with Idiopathic Autism in Simplex Families

    ERIC Educational Resources Information Center

    Liu, Xudong; Solehdin, Fatima; Cohen, Ira L.; Gonzalez, Maripaz G.; Jenkins, Edmund C.; Lewis, M. E. Suzanne; Holden, Jeanette J. A.

    2011-01-01

    Two methylenetetrahydrofolate reductase gene ("MTHFR") functional polymorphisms were studied in 205 North American simplex (SPX) and 307 multiplex (MPX) families having one or more children with an autism spectrum disorder. Case-control comparisons revealed a significantly higher frequency of the low-activity 677T allele, higher prevalence of the…

  5. Gene-specific DNA methylation of DNMT3B and MTHFR and colorectal adenoma risk.

    PubMed

    Ho, Vikki; Ashbury, Janet E; Taylor, Sherryl; Vanner, Stephen; King, Will D

    2015-12-01

    DNA methyltransferase 3B (DNMT3B) and methylenetetrahydrofolate reductase (MTHFR) are genes which encode enzymes critical to one-carbon metabolism. Polymorphisms in these genes have been implicated in colorectal cancer etiology; however, epigenetic modifications such as gene-specific DNA methylation also affect gene expression. DNA methylation of DNMT3B and MTHFR was quantified in blood leukocytes using Sequenom EpiTYPER(®) among 272 participants undergoing a screening colonoscopy. DNA methylation was quantified in 66 and 28CpG sites of DNMT3B and MTHFR respectively, and conceptualized using two approaches. First, measures representing average methylation across all CpG sites were created. Second, unsupervised principal component (PC) analysis was used to identify summary variables representing methylation around the transcription start site and in the gene-coding area for both DNMT3B and MTHFR. Logistic regression was used to compare methylation levels between participants diagnosed with colorectal adenoma(s) versus those with a normal colonoscopy via the estimation of odds ratios (ORs) and 95% confidence intervals (95% CIs) for the risk of colorectal adenomas. No association was observed between average DNA methylation of either DNMT3B or MTHFR and colorectal adenoma risk. For DNMT3B, increasing DNA methylation of CpG sites in the gene-coding area was associated with a higher risk of colorectal adenomas (OR=1.34; 95% CI: 1.01-1.79 per SD). This research provides preliminary evidence that methylation of DNMT3B may have functional significance with respect to colorectal adenomas, precursors to the vast majority of colorectal cancers. PMID:26485042

  6. Polymorphisms in MTHFR, MS and CBS Genes and Homocysteine Levels in a Pakistani Population

    PubMed Central

    Yakub, Mohsin; Moti, Naushad; Parveen, Siddiqa; Chaudhry, Bushra; Azam, Iqbal; Iqbal, Mohammad Perwaiz

    2012-01-01

    Background Hyperhomocysteinemia (>15 µmol/L) is highly prevalent in South Asian populations including Pakistan. In order to investigate the genetic determinants of this condition, we studied 6 polymorphisms in genes of 3 enzymes - methylenetetrahydrofolate reductase (MTHFR; C677T; A1298C), methionine synthase (MS; A2756G), cystathionine-?-synthase (CBS; T833C/844ins68, G919A) involved in homocysteine metabolism and investigated their interactions with nutritional and environmental factors in a Pakistani population. Methodology/Principal Findings In a cross-sectional survey, 872 healthy adults (355 males and 517 females; age 18–60 years) were recruited from a low-income urban population in Karachi. Fasting venous blood was obtained and assessed for plasma/serum homocysteine; folate, vitamin B12, pyridoxal phosphate and blood lead. DNA was isolated and genotyping was performed by PCR-RFLP (restriction-fragment-length- polymorphism) based assays. The average changes in homocysteine levels for MTHFR 677CT and TT genotypes were positive [?(SE ?), 2.01(0.63) and 16.19(1.8) µmol/L, respectively]. Contrary to MTHFR C677T polymorphism, the average changes in plasma homocysteine levels for MS 2756AG and GG variants were negative [?(SE ?), ?0.56(0.58) and ?0.83(0.99) µmol/L, respectively]. The average change occurring for CBS 844ins68 heterozygous genotype (ancestral/insertion) was ?1.88(0.81) µmol/L. The combined effect of MTHFR C677T, MS A2756G and CBS 844ins68 genotypes for plasma homocysteine levels was additive (p value <0.001). Odds of having hyperhomocysteinemia with MTHFR 677TT genotype was 10-fold compared to MTHFR 677CC genotype [OR (95%CI); 10.17(3.6–28.67)]. Protective effect towards hyperhomocysteinemia was observed with heterozygous (ancestral/insertion) genotype of CBS 844ins68 compared to homozygous ancestral type [OR (95% CI); 0.58 (0.34–0.99)]. Individuals with MTHFR 677CT or TT genotypes were at a greater risk of hyperhomocysteinemia in folate and vitamin B12 deficiencies and high blood lead (p value <0.05) level. Conclusions Gene polymorphism (especially MTHFR C677T transition), folate and vitamin B12 deficiencies, male gender and high blood lead level appear to be contributing towards the development of hyperhomocysteinemia in a Pakistani population. PMID:22470444

  7. Association between MTHFR gene polymorphisms and the risk of autism spectrum disorders: a meta-analysis.

    PubMed

    Pu, Danhua; Shen, Yiping; Wu, Jie

    2013-10-01

    Methylenetetrahydrofolate reductase (MTHFR) is essential for DNA biosynthesis and the epigenetic process of DNA methylation, and its gene polymorphisms have been implicated as risk factors for birth defects, neurological disorders, and cancers. However, reports on the association of MTHFR polymorphisms with autism spectrum disorders (ASD) are inconclusive. Therefore, we investigated the relationship of the MTHFR polymorphisms (C677T and A1298C) and the risk of ASD by meta-analysis. Up to December 2012, eight case-control studies involving 1672 patients with ASD and 6760 controls were included for meta-analysis. The results showed that the C677T polymorphism was associated with significantly increased ASD risk in all the comparison models [T vs. C allele (frequency of allele): odds ratio (OR) = 1.42, 95% confidence interval (CI): 1.09-1.85; CT vs. CC (heterozygote): OR = 1.48, 95% CI: 1.09-2.00; TT vs. CC (homozygote): OR = 1.86, 95% CI: 1.08-3.20; CT+TT vs. CC (dominant model): OR = 1.56, 95% CI: 1.12-2.18; and TT vs. CC+CT (recessive model): OR = 1.51, 95% CI: 1.02-2.22], whereas the A1298C polymorphism was found to be significantly associated with reduced ASD risk but only in a recessive model (CC vs. AA+AC: OR = 0.73, 95% CI: 0.56-0.97). In addition, we stratified the patient population based on whether they were from a country with food fortification of folic acid or not. The meta-analysis showed that the C677T polymorphism was found to be associated with ASD only in children from countries without food fortification. Our study indicated that the MTHFR C677T polymorphism contributes to increased ASD risk, and periconceptional folic acid may reduce ASD risk in those with MTHFR 677C>T polymorphism. PMID:23653228

  8. Correlation between MTHFR gene methylation and pre-eclampsia, and its clinical significance.

    PubMed

    Ge, J; Wang, J; Zhang, F; Diao, B; Song, Z F; Shan, L L; Wang, W; Cao, H J; Li, X Q

    2015-01-01

    We investigated the correlation between 5,10-methylenetetrahydrofolate reductase (MTHFR) gene methylation and pre-eclampsia, and its clinical significance, by comparing methylation in the MTHFR gene promoter of the placenta and peripheral venous blood in pre-eclampsia and normal gravidas. We enrolled 259 gravidas from the People's Liberation Army 202nd Hospital, China, between January 2011 and September 2011, including 127 pre-eclampsia and 132 nor-mal gravidas. Methylation levels of the MTHFR gene in placentas in two sets of gravidas were detected by methylation-specific polymerase chain reaction, plasma homocysteine levels were detected by enzyme-linked immunosorbent assay, and folic acid and vitamin B12 levels were detected by electrochemiluminescence. The chi-square test results were analyzed using the SPSS19.0 statistical software. In placentas, the methylation indices were 26.8% (34/127) and 15.2% (20/132) in the pre-eclampsia and normal groups, respectively (?(2) = 5.30, P < 0.05, odds ratio (OR) = 2.04, 95% confidence interval (95%CI) = 1.10-3.73). In peripheral venous blood, the methylation indices were 22.8% (29/127) and 12.1% (16/132) in pre-eclampsia and normal groups, respectively (?(2) = 5.17, P < 0.05, OR = 2.15, 95%CI = 1.11-4.15). The plasma methylation level of the pre-eclampsia group was consistent with the normal group. The plasma homocysteine level in the pre-eclampsia group was higher than in the normal group (P < 0.05). Levels of folic acid and vitamin B12 in the pre-eclampsia and normal groups were not statistically significant (P > 0.05). Patients with pre-eclampsia have hypermethylation in the MTHFR gene promoter, which may be one of its causes. PMID:26214484

  9. The Association between MTHFR Gene Polymorphisms and Hepatocellular Carcinoma Risk: A Meta-Analysis

    PubMed Central

    Deng, Yan; Huang, Shan; Xu, Juanjuan; Li, Haiwei; Li, Shan; Zhao, Jinmin

    2013-01-01

    Background The association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and hepatocellular carcinoma (HCC) risk was inconsistent and underpowered. To clarify the effects of MTHFR gene polymorphisms on the risk of HCC, a meta-analysis of all available studies relating C677T and/or A1298C polymorphisms of MTHFR gene to the risk of HCC was conducted. Methods The authors searched PubMed, EMBASE, Cochrane Library, Web of Science, and Chinese Biomedical Literature database (CBM) for the period up to July 2012. Data were extracted by two independent authors and pooled odds ratio (OR) with 95% confidence interval (CI) was calculated. Metaregression and subgroup analyses were performed to identify the source of heterogeneity. Results Finally, 12 studies with 2,351 cases and 4,091 controls were included for C677T polymorphism and 6 studies with 1,333 cases and 1,878 controls were included for A1298C polymorphism. With respect to A1298C polymorphism, significantly decreased HCC risk was found in the overall population (CC vs. AA: OR?=?0.660, 95%CI 0.460–0.946, P?=?0.024; recessive model: OR?=?0.667, 95%CI?=?0.470–0.948, P?=?0.024). In subgroup analyses, significantly decreased HCC risk was found in Asian population (CC vs. AA: OR?=?0.647, 95%CI?=?0.435–0.963; P?=?0.032) and population-based studies (CC vs. AA: OR?=?0.519, 95%CI?=?0.327–0.823; P?=?0.005). With respect to C677T polymorphism, no significant association with HCC risk was demonstrated in overall and stratified analyses. Conclusions We concluded that MTHFR A1298C polymorphism may play a protective role in the carcinogenesis of HCC. Further large and well-designed studies are needed to confirm this association. PMID:23457501

  10. Screening of polymorphisms for MTHFR and DHFR genes in spina bifida children and their mothers

    NASA Astrophysics Data System (ADS)

    Husna, M. Z.; Endom, I.; Ibrahim, S.; Selvi, N. Amaramalar; Fakhrurazi, H.; Htwe, R. Ohnmar; Kanehaswari, Y.; Halim, A. R. Abdul; Wong, S. W.; Subashini, K.; Syahira, O. Nur; Aishah, S.

    2013-11-01

    Mechanism underlying the beneficial effect of folic acid supplementation in reducing the risk of neural tube defect is still not well understood. Current evidences show the involvement of folic acid metabolic gene's polymorphism as contributing factors that regulate this pathway. Therefore, the objective of this research was to determine the presence of C677T polymorphism for methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase (DHFR-19 bp deletion) genes between mother-children pairs of case and control. With the approval of UKMMC ethic committee, genomic DNA was extracted from one hundred and forty consented bloods. Polymerase chain reaction (PCR), PCR-RFLP (Restriction Fragment Length Polymorphism) and sequencing were employed to verify each nucleotide change. Our result shows that mutant MTHFR and DHFR alleles are present in all Malaysian sub-ethnic groups, case and control. Even though mutant MTHFR are found to be slightly higher in the case groups, 75% of the affected child is a non carrier for this allele and 62.5% of the mothers with an affected child are genotypically normal. For DHFR, almost all (87.5-100%) investigated samples are a carrier or having a double DHFR deletion be it a case or control pairs. However, strong maternal inheritance shown by the deleted allele might be due to a cascade effect of lacks of folate consumption or maternal uniparental disomy. In conclusion, the use of MTHFR and DHFR as markers in determining the risk of having spina bifida baby is uninformative and plays a small indirect role as the genetic causes of spina bifida. Therefore, spina bifida remains etiologically unknown polygenic and quantitative developmental trait whereby the searches for positive genetic marker need to be continued.

  11. The association between MTHFR 677C>T genotype and folate status and genomic and gene-specific DNA methylation in the colon of individuals without colorectal neoplasia1234

    PubMed Central

    Hanks, Joanna; Ayed, Iyeman; Kukreja, Neil; Rogers, Chris; Harris, Jessica; Gheorghiu, Alina; Liu, Chee Ling; Emery, Peter

    2013-01-01

    Background: Decreased genomic and increased gene-specific DNA methylation predispose to colorectal cancer. Dietary folate intake and the methylenetetrahydrofolate reductase polymorphism (MTHFR 677C>T) may influence risk by modifying DNA methylation. Objective: We investigated the associations between MTHFR 677C>T genotype, folate status, and DNA methylation in the colon. Design: We conducted a cross-sectional study of 336 men and women (age 19–92 y) in the United Kingdom without colorectal neoplasia. We obtained blood samples for measurement of serum and red blood cell folate, plasma homocysteine, and MTHFR 677C>T genotype and colonic tissue biopsies for measurement of colonic tissue folate and DNA methylation (genomic- and gene-specific, estrogen receptor 1, ESR1; myoblast determination protein 1, MYOD1; insulin-like growth factor II, IGF2; tumor suppressor candidate 33, N33; adenomatous polyposis coli, APC; mut-L homolog 1, MLH1; and O6-methylguanine-DNA methyltransferase, MGMT) by liquid chromatography/electrospray ionization mass spectrometry and pyrosequencing, respectively. Results: Of the 336 subjects recruited, 185 (55%) carried the CC, 119 (35%) the CT, and 32 (10%) the TT alleles. No significant differences in systemic markers of folate status and colonic tissue folate between genotypes were found. The MTHFR TT genotype was not associated with genomic or gene-specific DNA methylation. Biomarkers of folate status were not associated with genomic DNA methylation. Relations between biomarkers of folate status and gene-specific methylation were inconsistent. However, low serum folate was associated with high MGMT methylation (P = 0.001). Conclusion: MTHFR 677C>T genotype and folate status were generally not associated with DNA methylation in the colon of a folate-replete population without neoplasia. This trial was registered at clinicaltrials.gov as ISRCTN43577261. PMID:24108782

  12. Homocysteine Metabolism Gene Polymorphisms (MTHFR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) Jointly Elevate the Risk of Folate Deficiency

    PubMed Central

    Li, Wen-Xing; Dai, Shao-Xing; Zheng, Jun-Juan; Liu, Jia-Qian; Huang, Jing-Fei

    2015-01-01

    Folate deficiency is strongly associated with cardiovascular disease. We aimed to explore the joint effect of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G polymorphisms on folate deficiency in a Chinese hypertensive population. A total of 480 subjects aged 28–75 were enrolled in this study from September 2005–December 2005 from six hospitals in different Chinese regions. Known genotypes were detected by PCR-RFLP methods and serum folate was measured by chemiluminescence immunoassay. Our results showed that MTHFR 677TT and MTR 2756AG + GG were independently associated with a higher risk of folate deficiency (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA p = 0.030, respectively). However, the MTHFR A1298C mutation may confer protection by elevating the serum folate level (p = 0.025). Furthermore, patients carrying two or more risk genotypes showed higher odds of folate deficiency than null risk genotype carriers, especially those carrying four risk genotypes. These findings were verified by generalized multifactor dimensionality reduction (p = 0.0107) and a cumulative effects model (p = 0.001). The results of this study have shown that interactions among homocysteine metabolism gene polymorphisms lead to dramatic elevations in the folate deficiency risk. PMID:26266420

  13. Homocysteine Metabolism Gene Polymorphisms (MTHFR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) Jointly Elevate the Risk of Folate Deficiency.

    PubMed

    Li, Wen-Xing; Dai, Shao-Xing; Zheng, Jun-Juan; Liu, Jia-Qian; Huang, Jing-Fei

    2015-08-01

    Folate deficiency is strongly associated with cardiovascular disease. We aimed to explore the joint effect of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G polymorphisms on folate deficiency in a Chinese hypertensive population. A total of 480 subjects aged 28-75 were enrolled in this study from September 2005-December 2005 from six hospitals in different Chinese regions. Known genotypes were detected by PCR-RFLP methods and serum folate was measured by chemiluminescence immunoassay. Our results showed that MTHFR 677TT and MTR 2756AG + GG were independently associated with a higher risk of folate deficiency (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA p = 0.030, respectively). However, the MTHFR A1298C mutation may confer protection by elevating the serum folate level (p = 0.025). Furthermore, patients carrying two or more risk genotypes showed higher odds of folate deficiency than null risk genotype carriers, especially those carrying four risk genotypes. These findings were verified by generalized multifactor dimensionality reduction (p = 0.0107) and a cumulative effects model (p = 0.001). The results of this study have shown that interactions among homocysteine metabolism gene polymorphisms lead to dramatic elevations in the folate deficiency risk. PMID:26266420

  14. Polymorphisms in the MTHFR gene are associated with breast cancer risk and prognosis in a Chinese population.

    PubMed

    Lu, Qing; Jiang, Ke; Li, Qiong; Ji, Ya-Jie; Chen, Wei-Li; Xue, Xiao-Hong

    2015-05-01

    Breast cancer is the most common cancer affecting women in China and the world. Folate supplementation is proven to be effective in reducing the risk of breast cancer or improving its prognosis. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism and DNA synthesis. This study aims to examine whether single nucleotide polymorphisms (SNP) in the MTHFR gene are associated with risk and survival of breast cancer and serum folate levels in healthy controls. We genotyped nine tagging SNPs in the MTHFR gene in a case-control study, including 560 breast cancer cases and 560 healthy controls in China. We found that TT genotype of rs1801133 had significant increased risk of breast cancer [adjusted odds ratio (OR)?= 1.60, 95 % confidence interval (CI) 1.12-2.28] compared with CC genotype, and CC genotype of rs9651118 conferred significant reduced risk of breast cancer (adjusted OR = 0.65, 95 % CI 0.45-0.95) compared to TT genotype. Haplotype analysis also showed that MTHFR CACCAA and AGTCAC haplotypes (rs12121543-rs13306553-rs9651118-rs1801133-rs4846048-rs1801131) had significant reduced risk of breast cancer (adjusted OR = 0.70, 95 % CI 0.58-0.86; adjusted OR = 0.57, 95 % CI 0.40-0.80) compared with CATTAA haplotype. Besides, MTHFR rs9651118 CC genotype was significantly associated with survival in breast cancer cases (adjusted hazard ratio (HR)?= 0.63, 95 % CI 0.40-0.99). But none of the SNPs in the MTHFR gene was associated with serum folate level in healthy controls. These findings suggest that variants in the MTHFR gene may influence the risk and prognosis of breast cancer. PMID:25566964

  15. Association of Polymorphisms in BDNF, MTHFR, and Genes Involved in the Dopaminergic Pathway with Memory in a Healthy Chinese Population

    ERIC Educational Resources Information Center

    Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen

    2012-01-01

    The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

  16. Association of Polymorphisms in BDNF, MTHFR, and Genes Involved in the Dopaminergic Pathway with Memory in a Healthy Chinese Population

    ERIC Educational Resources Information Center

    Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen

    2012-01-01

    The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

  17. Quantification of gene-specific methylation of DNMT3B and MTHFR using sequenom EpiTYPER®

    PubMed Central

    Ho, Vikki; Ashbury, Janet E.; Taylor, Sherryl; Vanner, Stephen; King, Will D.

    2015-01-01

    Among 272 patients undergoing a screening colonoscopy, DNA methylation of DNMT3B and MTHFR, genes encoding enzymes critical to one-carbon metabolism, was quantified in blood leukocytes using Sequenom EpiTYPER®. DNA methylation was quantified in 66 and 28 CpG sites of DNMT3B and MTHFR respectively, and conceptualized using two approaches. First, measures representing average methylation across all CpG sites were created. Second, unsupervised principal component (PC) analysis was used as a pattern derivation and data-reduction approach, to develop two summary variables (PC1 and PC2). These two summary variables represented methylation around the transcription start site (PC1) and in the gene-coding area (PC2) for both DNMT3B and MTHFR. The data contained in this article presents the variation of methylation levels for individual CpG sites within the DNMT3B and MTHFR genes and possible correlations uncovered using PC analysis. The data are related to the research article “Gene-specific DNA methylation of DNMT3B and MTHFR and colorectal adenoma risk” in Mutation Research – Fundamental and Molecular Mechanisms of Mutagenesis. PMID:26759827

  18. Quantification of gene-specific methylation of DNMT3B and MTHFR using sequenom EpiTYPER®.

    PubMed

    Ho, Vikki; Ashbury, Janet E; Taylor, Sherryl; Vanner, Stephen; King, Will D

    2016-03-01

    Among 272 patients undergoing a screening colonoscopy, DNA methylation of DNMT3B and MTHFR, genes encoding enzymes critical to one-carbon metabolism, was quantified in blood leukocytes using Sequenom EpiTYPER®. DNA methylation was quantified in 66 and 28 CpG sites of DNMT3B and MTHFR respectively, and conceptualized using two approaches. First, measures representing average methylation across all CpG sites were created. Second, unsupervised principal component (PC) analysis was used as a pattern derivation and data-reduction approach, to develop two summary variables (PC1 and PC2). These two summary variables represented methylation around the transcription start site (PC1) and in the gene-coding area (PC2) for both DNMT3B and MTHFR. The data contained in this article presents the variation of methylation levels for individual CpG sites within the DNMT3B and MTHFR genes and possible correlations uncovered using PC analysis. The data are related to the research article "Gene-specific DNA methylation of DNMT3B and MTHFR and colorectal adenoma risk" in Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis. PMID:26759827

  19. MTHFR Gene Polymorphisms and the Risk of Acute Lymphoblastic Leukemia in Adults and Children: A Case Control Study in India.

    PubMed

    Sazawal, Sudha; Chaubey, Rekha; Kaur, Pawandeep; Chikkara, Sunita; Kumar, Bijender; Bakshi, Sameer; Arya, L S; Raina, Vinod; Das Gupta, Alakananda; Saxena, Renu

    2014-12-01

    Genetic polymorphisms in the methylene tetrahydrofolate reductase (MTHFR) gene have been associated with the development of acute leukemias and various malignancies. The role of MTHFR polymorphism in the development of pediatric acute lymphoblastic leukemia (ALL) has been extensively studied among north Indians in various settings, yet its association with acute leukemias remains unresolved. To evaluate the relationship between functional MTHFR polymorphisms, C677T and A1298C and possible effect on risk of ALL in adults and children in North Indian population by comparing them with healthy controls. DNA was isolated from peripheral blood of 184 ALL patients (33 adults, 151 children) and 155 controls and analyzed by a PCR-restriction fragment length polymorphism assay. The frequency of MTHFR 677CT and 1298 AC genotypes were significantly lower among adult ALL cases when compared to the controls. We found a 1.74-fold reduced risk of ALL in individuals with 1298AC polymorphic variant and a 9.17-fold decreased risk of adult ALL. However, no statistically significant difference was evident between the above polymorphisms and susceptibility to ALL in children. Polymorphisms in the MTHFR gene possibly modulate risk of ALL in north Indian adults but not in children, although larger studies are needed. PMID:25435717

  20. Association of the rs1801133 variant in the MTHFR gene and sporadic Parkinson's disease.

    PubMed

    García, S; Coral-Vázquez, Rm; Gallegos-Arreola, M P; Montes-Almanza, L A; Canto, P; García-Martínez, F A; Chavira-Hernández, G; Palma-Flores, C; Dávila-Maldonado, L; Cuevas-García, C F; López Hernández, L B

    2015-01-01

    The MTHFR gene has been reported as a susceptibility locus for sporadic Parkinson's disease (sPD). The functional variant rs1801133 has been linked to hyperhomocysteinemia and dopaminergic cell death. Among different populations, Mexican-Mestizos (most present-day Mexicans) have the highest frequency of this variant. Therefore, we sought to determine a possible association of rs1801133 with SPD. In total, 356 individuals were included: 140 patients with PD, diagnosed according to the Queen Square Brain Bank criteria, and 216 neurologically healthy controls. Genotyping was performed using TaqMan probes for rs1801133 and real-time PCR. Logistic regression analysis with adjustment for smoking and gender was used to test for an association between genotype and SPD. The CC genotype was associated with SPD; exp() = 2.06; 95% CI: 1.101-3.873, p = 0.024. No association with age at onset, cognitive impairment or gender was found in our study group. Our data suggest an important role of MTHFR gene variants in SPD. PMID:25909872

  1. A Study on MTHFR C677T Gene Polymorphism and Alcohol Dependence among Meiteis of Manipur, India

    PubMed Central

    Singh, Huidrom Suraj; Salam, Kabita; Saraswathy, Kallur Nava

    2014-01-01

    Chronic alcohol consumption is reported to be associated with increase in plasma homocysteine levels which is further influenced by the polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene. The present study aims to understand the extent of the MTHFR C677T polymorphism in alcohol dependent (AD) cases of Meiteis of Manipur, a Mendelian population of India. MTHFR C677T polymorphism was screened in 313 controls and 139 alcohol dependent (AD) cases who all met DSM-IV criteria for alcohol dependence. Both AD cases and controls were unrelated up to 1st cousin. Among the control group, different drinking patterns like abstainer/nondrinkers (NDs), occasional drinkers (ODs), and moderate drinkers (MDs) are included. Both the groups were found to be in Hardy-Weinberg equilibrium (P > 0.05). Genotypic and allelic frequency distribution of MTHFR C677T polymorphism did not differ significantly between AD cases and controls (P > 0.05). However, individuals carrying mutant (T) allele show more than 1-fold increased risk for AD though not significant (OR?=?1.43; 95% CI 0.41–5.01, P > 0.05). In conclusion, MTHFR C677T polymorphism is not found to be risk marker for AD in present studied population. However, higher prevalence of the mutant T allele may exacerbate deleterious health risk in future especially among alcohol drinkers. PMID:26317030

  2. Short Communication: Lack of association between MTHFR gene polymorphisms and response to methotrexate treatment in Pakistani patients with rheumatoid arthritis.

    PubMed

    Iqbal, Mohammad Perwaiz; Ali, Azra Arif; Mehboobali, Naseema; Iqbal, Khalida

    2015-09-01

    Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms have been reported to be associated with response to methotrexate (MTX) in certain populations of patients with rheumatoid arthritis (RA). This study aims at investigating any relationship of two single nucleotide polymorphisms (SNPs) in MTHFR gene, C677T and A1298C with response to therapy with MTX in Pakistani RA patients. Allelic frequencies of the two polymorphisms (C677T and A1298C) were determined in 67 RA patients (9 males and 58 females; mean age 42.87 ± 13.5 years) who had previously participated in a prospective clinical trial. Fifty-one patients had received MTX and were followed up for response up to 6 months. Genotyping of the two MTHFR polymorphisms was carried out using PCR-RFLP, while fasting concentration of plasma homocysteine was determined using a kit method. Twenty-eight patients were found to be "good responders", while twenty-three were "poor responders". MTHFR 1298C and MTHFR 677T alleles' frequencies in "good responders" were not different from frequencies in "poor responders" (0.574 vs. 0.521; p=0.6 and 0.197 vs. 0.196; p=0.75, respectively). Plasma homocysteine levels in female RA patients were significantly higher compared to general population in Karachi (13.1 ± 6.7 µmol/l vs. 11.4 ± 5.3 µmol/l; p<0.001). MTHFR C677T and A1298C polymorphisms are not associated with response to MTX in a population of Pakistani RA patients. PMID:26408898

  3. Association between MTHFR 677C/T and 1298A/C gene polymorphisms and breast cancer risk.

    PubMed

    Zhang, X F; Liu, T; Li, Y; Li, S

    2015-01-01

    We performed a case-control study to investigate the association between single nucleotide polymorphisms in the MTHFR gene (677C/T and 1298A/C) and risk of breast cancer. This case-control study included 216 breast cancer cases and 216 controls. The MTHFR 677C/T and 1298A/C gene polymorphisms were assessed by polymerase chain reaction restriction fragment length polymorphism. We observed an increased likelihood of breast cancer patients having a higher age at menarche and first live birth, and a greater family history of breast cancer, especially among first-degree relatives. In addition, individuals with the TT genotype of MTHFR 677C/T were associated with increased risk of breast cancer by logistic regression analysis; the adjusted odds ratio (95%CI) was 3.05 (1.17-8.87). In conclusion, the results of our study indicated that the MTHFR C677T gene polymorphism could play a role in the development of breast cancer. PMID:26662439

  4. Polymorphisms in NOS3, MTHFR, APOB and TNF-α Genes and Risk of Coronary Atherosclerotic Lesions in Iranian Patients

    PubMed Central

    Heidari, Mohammad Mehdi; Khatami, Mehri; Hadadzadeh, Mehdi; Kazemi, Mahbobeh; Mahamed, Sahar; Malekzadeh, Pegah; Mirjalili, Massomeh

    2015-01-01

    Background: Atherosclerosis is a complex multifocal arterial disease involving interactions between multiple genetic and environmental factors. Objectives: In the present study, we investigated the possible association between NOS3 (rs1799983), MTHFR (rs1801133), APOB (rs5742904) and TNF-α (rs361525) polymorphisms and the risk of coronary atherosclerotic lesions in Iranian patients. Patients and Methods: In the case-control study, 108 patients with coronary atherosclerosis disease and 95 control subjects with no family history of cardiovascular disease were enrolled. Genotypes for NOS3, MTHFR, APOB and TNF-α polymorphisms were identified using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). Results: We specifically detected the NOS3 TT genotype in 12 patients (11.11%) and did not find the same genotype in any of the controls. The frequencies of T allele in patients and the controls were 24% and 17.8%, respectively. The prevalence of the MTHFR TT genotype was 16.7% in patients and 2.2% in control groups. The prevalence of the APOB-100 (R3500Q) mutation in this patient population was 0%. The frequency of the A allele in the TNF-α gene was 11.1% and 11% in patients and controls, respectively, and the AA genotype was undetected. Conclusions: Our results show a significant association of NOS3 and MTHFR gene polymorphisms with coronary atherosclerotic lesions. Therefore, these variants might influence the risk of coronary artery disease, specifically in the Iranian population. PMID:26878010

  5. Spectrum of MTHFR gene SNPs C677T and A1298C: a study among 23 population groups of India.

    PubMed

    Saraswathy, Kallur Nava; Asghar, Mohammad; Samtani, Ratika; Murry, Benrithung; Mondal, Prakash Ranjan; Ghosh, Pradeep Kumar; Sachdeva, Mohinder Pal

    2012-04-01

    Elevated homocysteine is a risk factor for many complex disorders. The role of methylenetetrahydrofolate reductase (MTHFR) gene in methylation of homocysteine makes it one of the most important candidate genes for these disorders. Considering the heterogeneity in its distribution in world populations, we screened MTHFR C677T and A1298C single nucleotide polymorphisms in a total of 23 Indian caste, tribal and religious population groups from five geographical regions of India and belonging to four major linguistic groups. The frequencies of MTHFR 677T and 1298C alleles were found to be 10.08 and 20.66%, respectively. MTHFR homozygous genotype 677TT was absent in eight population groups and homozygous 1298CC was absent in two population groups. 677T allele was found to be highest among north Indian populations with Indo-European tongue and 1298C was high among Dravidian-speaking tribes of east India and south India. The less common mutant haplotype 677T-1298C was observed among seven population groups and overall the frequency of this haplotype was 0.008, which is similar to that of African populations. cis configuration of 677T and 1298C was 0.94%. However, we could not find any individual with four mutant alleles which supports the earlier observation that presence of more than two mutant alleles may decrease the viability of foetus and possibly be a selective disadvantage in the population. PMID:22147263

  6. Association of the APOE, MTHFR and ACE Genes Polymorphisms and Stroke in Zambian Patients

    PubMed Central

    Atadzhanov, Masharip; Mwaba, Mwila H.; Mukomena, Patrice N.; Lakhi, Shabir; Rayaprolu, Sruti; Ross, Owen A.; Meschia, James F.

    2013-01-01

    The aim of the present study was to investigate the association of APOE, MTHFR and ACE polymorphisms with stroke in the Zambian population. We analyzed 41 stroke patients and 116 control subjects all of Zambian origin for associations between the genotype of the APOE, MTHFR and ACE polymorphisms and stroke. The APOE ?2?4 genotype showed increased risk for hemorrhagic stroke (P<0.05) and also a high risk for ischemic stroke (P=0.05). There was complete absence of the APOE ?2?2 and the MTHFR TT genotypes in the Zambian population. The difference between cases and controls was not significant for the other genetic variants when analyzed for relationship between stroke, stroke subtype and genotype. We show that genetic variation at the APOE locus affects susceptibility to stroke. No detectable association were observed for the MTHFR and ACE genotypes and stroke in the Zambian population. PMID:24416484

  7. Effect of MTHFR Gene Polymorphism Impact on Atherosclerosis via Genome-Wide Methylation

    PubMed Central

    Lin, Xuefeng; Zhang, Wei; Lu, Qun; Lei, Xinjun; Wang, Tingzhong; Han, Xuanmao; Ma, Aiqun

    2016-01-01

    Background Atherosclerosis seriously threats human health. Homocysteine is an independent risk factor closely related to DNA methylation. MTHFR C667T loci polymorphism is closely associated with homocysteine level. This study aimed to investigate the relationship among MTHFR C667T loci polymorphism, genome-wide methylation, and atherosclerosis. Material/Methods Blood sample was collected from 105 patients with coronary atherosclerosis and 105 healthy controls. Pyrosequencing methylation was used to detect LINE-1 methylation level. Polymerase chain reaction-restriction enzyme fragment length polymorphism (PCR-RFLP) was used to test MTHFR. Results LINE-1 methylation level in the patient group was significantly lower than in the controls (t=5.007, P<0.001). MTHFR C667T genotype distribution presented marked differences in the 2 groups. TT genotype carriers had significantly increased risk of atherosclerosis (OR=3.56, P=0.009). Three different genotypes of MTHFR C667T loci showed different LINE-1 methylation level between the 2 groups (P<0.01). LINE-1 methylation level in TT and CT genotype carriers was obviously lower than in CC genotype carriers (P<0.05). Conclusions MTHFR C667T loci polymorphism may affect atherosclerosis by regulating genome methylation level. PMID:26828698

  8. Effect of MTHFR Gene Polymorphism Impact on Atherosclerosis via Genome-Wide Methylation.

    PubMed

    Lin, Xuefeng; Zhang, Wei; Lu, Qun; Lei, Xinjun; Wang, Tingzhong; Han, Xuanmao; Ma, Aiqun

    2016-01-01

    BACKGROUND Atherosclerosis seriously threats human health. Homocysteine is an independent risk factor closely related to DNA methylation. MTHFR C667T loci polymorphism is closely associated with homocysteine level. This study aimed to investigate the relationship among MTHFR C667T loci polymorphism, genome-wide methylation, and atherosclerosis. MATERIAL AND METHODS Blood sample was collected from 105 patients with coronary atherosclerosis and 105 healthy controls. Pyrosequencing methylation was used to detect LINE-1 methylation level. Polymerase chain reaction-restriction enzyme fragment length polymorphism (PCR-RFLP) was used to test MTHFR. RESULTS LINE-1 methylation level in the patient group was significantly lower than in the controls (t=5.007, P<0.001). MTHFR C667T genotype distribution presented marked differences in the 2 groups. TT genotype carriers had significantly increased risk of atherosclerosis (OR=3.56, P=0.009). Three different genotypes of MTHFR C667T loci showed different LINE-1 methylation level between the 2 groups (P<0.01). LINE-1 methylation level in TT and CT genotype carriers was obviously lower than in CC genotype carriers (P<0.05). CONCLUSIONS MTHFR C667T loci polymorphism may affect atherosclerosis by regulating genome methylation level. PMID:26828698

  9. Associations of Polymorphisms in MTHFR Gene with the Risk of Age-Related Cataract in Chinese Han Population: A Genotype-Phenotype Analysis

    PubMed Central

    Wei, Li; Han, Ya-di; Cui, Ning-hua; Huang, Zhu-liang; Li, Zu-hua; Zheng, Fang; Yan, Ming

    2015-01-01

    Homocysteine (Hcy) is a potential risk factor for age-related cataract (ARC). Methylenetetrahydrofolate reductase (MTHFR) is the key enzyme for Hcy metabolism, and variants of MTHFR may affect MTHFR enzyme activity. This study mainly evaluated the associations between variants in MTHFR gene, plasma MTHFR enzyme activity, total Hcy (tHcy) levels and ARC risk in Chinese population. Four single nucleotide polymorphisms (SNPs) in MTHFR gene were genotyped using the high-resolution melting (HRM) method in 502 ARC patients (mean age, 70.2 [SD, 9.0], 46.0% male) and 890 healthy controls (mean age, 67.1 [SD, 11.1], 47.6% male). The plasma MTHFR activity, folic acid (FA), vitamins B12 and B6 levels were detected by enzyme-linked immunosorbent assays (ELISA). The plasma tHcy levels were measured by an automated enzymatic assay. After the Bonferroni correction, the minor allele T of SNP rs1801133 showed a significant association with an increased risk of overall ARC (OR = 1.26, P = 0.003). Consistent association was also found between SNP rs1801133 and cortical ARC risk (OR = 1.44, P = 0.003). Haplotype analyses revealed an adverse effect of the haplotype "C-A-T-C" (alleles in order of SNPs rs3737967, rs1801131, rs1801133 and rs9651118) on ARC risk (OR = 1.55, P = 0.003). Moreover, in a joint analysis of SNPs rs9651118 and rs1801133, subjects with two unfavorable genotypes had a 1.76-fold increased risk of ARC compared with the reference group, and a statistically significant dose-response trend (Ptrend = 0.001) was also observed. Further, in healthy controls and patients with cortical ARC, the allele T of SNP rs1801133 and the increasing number of unfavorable genotypes were significantly correlated with decreased MTHFR activity as well as increased tHcy levels. However, there was no significant association between FA, vitamins B12, B6 levels and MTHFR variants. Our data indicated that variants in MTHFR gene might individually and jointly influence susceptibility to ARC by affecting MTHFR enzyme activity and tHcy levels. PMID:26689687

  10. Common folate gene variant, MTHFR C677T, is associated with brain structure in two independent cohorts of people with mild cognitive impairment☆

    PubMed Central

    Rajagopalan, Priya; Jahanshad, Neda; Stein, Jason L.; Hua, Xue; Madsen, Sarah K.; Kohannim, Omid; Hibar, Derrek P.; Toga, Arthur W.; Jack, Clifford R.; Saykin, Andrew J.; Green, Robert C.; Weiner, Michael W.; Bis, Joshua C.; Kuller, Lewis H.; Riverol, Mario; Becker, James T.; Lopez, Oscar L.; Thompson, Paul M.

    2012-01-01

    A commonly carried C677T polymorphism in a folate-related gene, MTHFR, is associated with higher plasma homocysteine, a well-known mediator of neuronal damage and brain atrophy. As homocysteine promotes brain atrophy, we set out to discover whether people carrying the C677T MTHFR polymorphism which increases homocysteine, might also show systematic differences in brain structure. Using tensor-based morphometry, we tested this association in 359 elderly Caucasian subjects with mild cognitive impairment (MCI) (mean age: 75 ± 7.1 years) scanned with brain MRI and genotyped as part of Alzheimer's Disease Neuroimaging Initiative. We carried out a replication study in an independent, non-overlapping sample of 51 elderly Caucasian subjects with MCI (mean age: 76 ± 5.5 years), scanned with brain MRI and genotyped for MTHFR, as part of the Cardiovascular Health Study. At each voxel in the brain, we tested to see where regional volume differences were associated with carrying one or more MTHFR ‘T’ alleles. In ADNI subjects, carriers of the MTHFR risk allele had detectable brain volume deficits, in the white matter, of up to 2–8% per risk T allele locally at baseline and showed accelerated brain atrophy of 0.5–1.5% per T allele at 1 year follow-up, after adjusting for age and sex. We replicated these brain volume deficits of up to 5–12% per MTHFR T allele in the independent cohort of CHS subjects. As expected, the associations weakened after controlling for homocysteine levels, which the risk gene affects. The MTHFR risk variant may thus promote brain atrophy by elevating homocysteine levels. This study aims to investigate the spatially detailed effects of this MTHFR polymorphism on brain structure in 3D, pointing to a causal pathway that may promote homocysteine-mediated brain atrophy in elderly people with MCI. PMID:24179750

  11. Interaction of MTHFR C677T and A1298C, and MTR A2756G gene polymorphisms in breast cancer risk in a population in Northeast Brazil.

    PubMed

    de Cássia Carvalho Barbosa, Rita; da Costa, Débora Menezes; Cordeiro, Denise Ellen Francelino; Vieira, Ana Patricia Freitas; Rabenhorst, Silvia Helena Barem

    2012-11-01

    Polymorphisms in genes encoding enzymes of folate metabolism are a focus of breast cancer risk studies due of the role of these enzymes in DNA methylation, synthesis, and repair. MTHFR, encoding for 5,10-methylenetetrahydrofolate reductase, is one of the most studied genes in this regard, but findings are controversial, and the majority of studies have analyzed polymorphisms individually. In this case control study, we examined the combination of the polymorphisms MTHFR C677T and A1298C with MTR A2756G, where MTR, methionine synthase, is an important enzyme of the folate cycle in the methylation pathway. One hundred and forty-two patients with breast cancer and controls were included and the genotypes were determined using PCR-RFLP. In the population studied, individuals carrying the polymorphic allele in the heterozygous state for both enzymes, MTHFR C677T and MTR A2756G, had an increased risk [odds ratio, OR=2.77 (95% confidence interval, CI=1.19-6.52)] for disease, compared to those with the wild genotype. In addition, individuals carrying the MTR 2756 genotype AG had an increased risk when this was combined with the MTHFR 1298 genotype CC [OR=5.13 (95% CI=0.87-38.82)]. No significant results were found from the analyses associating the MTHFR C677T and A1298C genotypes. However, when stratifying the patients by age (50 years old as the cut-off), patients over 50 years old had greater risk, with the presence of both MTHFR polymorphisms in the heterozygous state [OR=5.33 (95% CI=1.42-21.03)]. This study points out the importance of the interactions between the MTHFR C677T, MTHFR A1298C and MTR A2756G polymorphisms, and also highlights the relevance of the MTR A2756G polymorphism and age in breast cancer risk. PMID:23155246

  12. A C677T methylenetetrahydrofolate reductase (MTHFR) polymorphism and G20210A mutation in the prothrombin gene of sickle cell anemia patients from Northeast Brazil.

    PubMed

    Couto, Fábio David; Boas, Wendell Vilas; Lyra, Isa; Zanette, Angela; Dupuit, Marie France; Almeida, Mari Ney Tavares; Reis, Mitermayer Galvão; Gonçalves, Marilda Souza

    2004-08-01

    The C677T methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and the G20210A mutation at the 3' untranslated region (3'UTR) of the prothrombin gene may be considered to be genetic risk factors that contribute to the clinical heterogeneity in sickle cell disease. The current study investigated a group of sickle cell (SS) patients from Salvador-Bahia, Northeast Brazil in order to determine the prevalence of these polymorphisms, using the polymerase chain reaction (PCR) and restriction fragment length polymorphim (RFLP) techniques. Out of 69 SS patients diagnosed with the C677T MTHFR gene polymorphism, 13 (18.6%) were heterozygous and four (5.7%) homozygous. The G20210A mutation was not found in 50 SS patients investigated. These results became important once the C677T MTHFR gene polymorphism was found to be an independent risk factor for vascular disease, a common clinical event in sickle cell disease. PMID:15481892

  13. Candidate colorectal cancer predisposing gene variants in Chinese early-onset and familial cases

    PubMed Central

    Zhang, Jun-Xiao; Fu, Lei; de Voer, Richarda M; Hahn, Marc-Manuel; Jin, Peng; Lv, Chen-Xi; Verwiel, Eugène TP; Ligtenberg, Marjolijn JL; Hoogerbrugge, Nicoline; Kuiper, Roland P; Sheng, Jian-Qiu; Geurts van Kessel, Ad

    2015-01-01

    AIM: To investigate whether whole-exome sequencing may serve as an efficient method to identify known or novel colorectal cancer (CRC) predisposing genes in early-onset or familial CRC cases. METHODS: We performed whole-exome sequencing in 23 Chinese patients from 21 families with non-polyposis CRC diagnosed at ≤ 40 years of age, or from multiple affected CRC families with at least 1 first-degree relative diagnosed with CRC at ≤ 55 years of age. Genomic DNA from blood was enriched for exome sequences using the SureSelect Human All Exon Kit, version 2 (Agilent Technologies) and sequencing was performed on an Illumina HiSeq 2000 platform. Data were processed through an analytical pipeline to search for rare germline variants in known or novel CRC predisposing genes. RESULTS: In total, 32 germline variants in 23 genes were identified and confirmed by Sanger sequencing. In 6 of the 21 families (29%), we identified 7 mutations in 3 known CRC predisposing genes including MLH1 (5 patients), MSH2 (1 patient), and MUTYH (biallelic, 1 patient), five of which were reported as pathogenic. In the remaining 15 families, we identified 20 rare and novel potentially deleterious variants in 19 genes, six of which were truncating mutations. One previously unreported variant identified in a conserved region of EIF2AK4 (p.Glu738_Asp739insArgArg) was found to represent a local Chinese variant, which was significantly enriched in our early-onset CRC patient cohort compared to a control cohort of 100 healthy Chinese individuals scored negative by colonoscopy (33.3% vs 7%, P < 0.001). CONCLUSION: Whole-exome sequencing of early-onset or familial CRC cases serves as an efficient method to identify known and potential pathogenic variants in established and novel candidate CRC predisposing genes. PMID:25892863

  14. Association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphism with ischemic stroke in the Eastern Chinese Han population.

    PubMed

    Lv, Q-Q; Lu, J; Sun, H; Zhang, J-S

    2015-01-01

    The association between the MTHFR genetic polymorphism and ischemic stroke has been reported by a number of investigators. However, the results have been controversial and conflicting. The aim of this study was to explore the association between the MTHFR variants C677T and A1298C and the risk of ischemic stroke in an Eastern Chinese Han population. A total of 199 patients with ischemic stroke and 241 controls were recruited. Genotyping of the MTHFR C677T and A1298C polymorphisms was carried out using the Taqman 7900HT Sequence Detection System. The overall estimates (odds ratio: OR) for the allele (C) and genotype (AC+CC) of the A1298C polymorphism were 1.57 [95% confidence interval (CI) = 1.16-2.10], and 2.36 (95%CI = 1.39-4.00), respectively, establishing significant association of the MTHFR A1298C polymorphism with ischemic stroke. In contrast, there were no statistically significant differences compared to controls between MTHFR C677T polymorphic variants in the association ischemic stroke risk. Furthermore, haplotype-based analysis demonstrated that compared with the C-677-A-1298 haplotype, the C-677-C-1298 and T-677-C-1298 haplotypes showed significant increased risk of ischemic stroke (OR = 1.56; 95%CI = 1.07- 2.2; P = 0.02; OR = 1.76; 95%CI = 1.17-2.65; P < 0.01, respectively). We concluded that the A1298C polymorphism and the haplotypes C-677-C-1298 and T-677-C-1298 in MTHFR might modulate the risk of ischemic stroke in the Eastern Chinese Han population. PMID:25966188

  15. MTHFR gene A1298C polymorphisms are associated with breast cancer risk among Chinese population: evidence based on an updated cumulative meta-analysis

    PubMed Central

    Wang, Yadong; Yang, Haiyan; Duan, Guangcai

    2015-01-01

    Objectives: Published studies on the association between methylenetetrahydrofolate reductase (MTHFR) gene A1298C polymorphisms and breast cancer risk among Chinese population have yielded conflicting results. The purpose of this study was to clarify the association between MTHFR gene A1298C polymorphisms and breast cancer risk among Chinese population. Methods: Systematic searches were performed through the database of Medline/PubMed, Science Direct, Elsevier, CNKI and Wanfang Medical Online. Results: Overall, a significantly increased risk of breast cancer was observed among the subjects carrying MTHFR gene A1298C AC+CC genotype (odds ratio [OR]=1.05 with 95% confidence interval [CI]: 1.01-1.10) as compared to those carrying AA genotype among total Chinese population. We did not observe any significant association between MTHFR gene A1298C polymorphisms and the risk of breast cancer under the additional genetic models of AC vs. AA, CC vs. AA and C-allele vs. A-allele (OR=1.00 with 95% CI: 0.97-1.02, OR=1.01 with 95% CI: 1.00-1.02 and OR=1.00 with 95% CI: 0.99-1.02, respectively). The cumulative meta-analysis showed similar results. In subgroup analysis, we observed subjects carrying AC+CC genotype had an increased breast cancer risk compared with those carrying AA genotype among the studies of sample size less than 1000. We did not observe any significant association between MTHFR gene A1298C polymorphisms and breast cancer risk in additional subgroup analyses. Conclusions: Our results suggest that MTHFR gene A1298C AC+CC genotype may be a risk factor for the development of breast cancer among Chinese population. Well-designed studies with a large sample size are needed to further confirm our findings.

  16. Severe arterial thrombophilia associated with a homozygous MTHFR gene mutation (A1298C) in a young man with Klinefelter syndrome.

    PubMed

    Ozbek, Mustafa; Oztürk, M Akif; Ureten, Kemal; Ceneli, Ozcan; Erdogan, Mehmet; Haznedaroglu, Ibrahim C

    2008-07-01

    Klinefelter syndrome (KS) is the most common sex chromosome disorder in men. It may be associated with an increased risk for venous thrombosis and thromboembolism, which is partially explained by hypofibrinolysis due to androgen deficiency. Additional genetic or acquired thrombophilic states have been shown in KS patients complicated with venous thrombosis as isolated case reports. Arterial thrombotic events had not been previously reported in KS. In this study, a young man with KS who developed acute arterial thrombosis during testosterone replacement therapy is presented. He was homozygous for the A1298C mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. PMID:18160591

  17. The 844ins68 cystathionine beta-synthase and C677T MTHFR gene polymorphism and the vaso-occlusive event risk in sickle cell disease

    PubMed Central

    Alves Jacob, Maza; da Cunha Bastos, Celso; Regina Bonini-Domingos, Claudia

    2011-01-01

    Introduction Sickle cell disease (SCD) is an inflammatory condition with an increase in the adhesion of sickled erythrocytes, and it is a potential cause of vaso-occlusive episodes, an event related to clinical manifestations, morbidity and mortality. The cystathionine beta-synthase enzyme gene (CBS) and the methylenetetrahydrofolate reductase enzyme gene (MTHFR) are risk factors for thromboembolic disorders. This study evaluated the frequency of the 844ins68 CBS and C677T MTHFR gene polymorphisms and their possibility to be risk factors for vaso-occlusive crises. Material and methods In total 91 blood samples from SCD patients were studied by PCR-RFLP and PCR-allele-specific, for the SCD genotype confirmation and polymorphism identification. Results The presence of clinical manifestations related to vaso-occlusive crises were more frequent among patients with the Hb SS genotype (p = 0.007). The CBS enzyme gene was three times more frequent (p = 0.011) among patients with vaso-occlusive complications. The MTHFR gene mutation frequency showed no increased risk for vaso-occlusive crises in SCD patients (p = 0.193). The interaction between the two polymorphisms was evaluated in 12.08% of the SCD patients and doubled the vaso-occlusive disease risk (relative risk: 2.16). Conclusions We conclude that the presence of 844ins68 CBS and C677T MTHFR gene polymorphism was a risk factor for vaso-occlusive episodes in the SCD patients evaluated. PMID:22291740

  18. MTHFR gene polymorphism and risk of myeloid leukemia: a meta-analysis.

    PubMed

    Dong, Song; Liu, Yueling; Chen, Jieping

    2014-09-01

    An increasing body of evidence has shown that the amino acid changes at position 1298 might eliminate methylenetetrahydrofolate reductase (MTHFR) enzyme activity, leading to insufficient folic acid and subsequent human chromosome breakage. Epidemiological studies have linked MTHFR single-nucleotide polymorphism (SNP) rs1801131 to myeloid leukemia risk, with considerable discrepancy in their results. We therefore were prompted to clarify this issue by use of a meta-analysis. The search terms were used to cover the possible reports in the MEDLINE, Web of Knowledge, and China National Knowledge Infrastructure (CNKI) databases. Odds ratios were estimated to assess the association of SNP rs1801131 with myeloid leukemia risk. Statistical heterogeneity was detected using the Q-statistic and I (2) metric. Subgroup analysis was performed by ethnicity, histological subtype, and Hardy-Weinberg equilibrium (HWE). This meta-analysis of eight publications with a total of 1,114 cases and 3,227 controls revealed no global association. Nor did the subgroup analysis according to histological subtype and HWE show any significant associations. However, Asian individuals who harbored the CC genotype were found to have 1.66-fold higher risk of myeloid leukemia (odds ratio, 1.66; 95 % confidence interval, 1.10 to 2.49; P h?=?0.342; I (2)?=?0.114). Our meta-analysis has presented evidence supporting a possible association between the CC genotype of MTHFR SNP rs1801131 and myeloid leukemia in Asian populations. PMID:24894669

  19. Homocysteine and the C677T Gene Polymorphism of Its Key Metabolic Enzyme MTHFR Are Risk Factors of Early Renal Damage in Hypertension in a Chinese Han Population.

    PubMed

    Yun, Lin; Xu, Rui; Li, Guohua; Yao, Yucai; Li, Jiamin; Cong, Dehong; Xu, Xingshun; Zhang, Lihua

    2015-12-01

    The combined hyperhomocysteinemia condition is a feature of the Chinese hypertensive population. This study used the case-control method to investigate the association between plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme, 5, 10-methylenetetrahydrofolate reductase (MTHFR), and early renal damage in a hypertensive Chinese Han population.A total of 379 adult essential hypertensive patients were selected as the study subjects. The personal information, clinical indicators, and the C677T gene polymorphism of MTHFR were texted. This study used the urine microalbumin/urine creatinine ratio (UACR) as a grouping basis: the hypertension without renal damage group (NRD group) and the hypertension combined with early renal damage group (ERD group).Early renal damage in the Chinese hypertensive population was associated with body weight, systolic pressure, diastolic pressure, urea nitrogen, serum creatinine, cystatin C, uric acid, aldosterone, and glomerular filtration rate. The homocysteine level and the UACR in the TT genotype group were higher than those in the CC genotype group. The binary logistic regression analysis results showed that after sex and age were adjusted, the MTHFR C677T gene polymorphism was correlated with early renal damage in hypertension in both the recessive model and in the additive model.Plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme MTHFR might be independent risk factors of early renal damage in the hypertensive Chinese Han population. PMID:26717388

  20. Variation in Telangiectasia Predisposing Genes Is Associated With Overall Radiation Toxicity

    SciTech Connect

    Tanteles, George A.; Department of Cancer Studies and Molecular Medicine, University Hospitals of Leicester, Leicester Royal Infirmary, Leicester ; Murray, Robert J.S.; Mills, Jamie; Barwell, Julian; Department of Cancer Studies and Molecular Medicine, University Hospitals of Leicester, Leicester Royal Infirmary, Leicester ; Chakraborti, Prabir; Chan, Steve; Cheung, Kwok-Leung; Ennis, Dawn; Khurshid, Nazish; Lambert, Kelly; Machhar, Rohan; Meisuria, Mitul; Osman, Ahmed; Peat, Irene; Sahota, Harjinder; Woodings, Pamela; Talbot, Christopher J.; and others

    2012-11-15

    Purpose: In patients receiving radiotherapy for breast cancer where the heart is within the radiation field, cutaneous telangiectasiae could be a marker of potential radiation-induced heart disease. We hypothesized that single nucleotide polymorphisms (SNPs) in genes known to cause heritable telangiectasia-associated disorders could predispose to such late, normal tissue vascular damage. Methods and Materials: The relationship between cutaneous telangiectasia as a late normal tissue radiation injury phenotype in 633 breast cancer patients treated with radiotherapy was examined. Patients were clinically assessed for the presence of cutaneous telangiectasia and genotyped at nine SNPs in three candidate genes. Candidate SNPs were within the endoglin (ENG) and activin A receptor, type II-like 1 (ACVRL1) genes, mutations in which cause hereditary hemorrhagic telangiectasia and the ataxia-telangiectasia mutated (ATM) gene associated with ataxia-telangiectasia. Results: A total of 121 (19.1%) patients exhibited a degree of cutaneous telangiectasiae on clinical examination. Regression was used to examine the associations between the presence of telangiectasiae in patients who underwent breast-conserving surgery, controlling for the effects of boost and known brassiere size (n=388), and individual geno- or haplotypes. Inheritance of ACVRL1 SNPs marginally contributed to the risk of cutaneous telangiectasiae. Haplotypic analysis revealed a stronger association between inheritance of a ATM haplotype and the presence of cutaneous telangiectasiae, fibrosis and overall toxicity. No significant association was observed between telangiectasiae and the coinheritance of the candidate ENG SNPs. Conclusions: Genetic variation in the ATM gene influences reaction to radiotherapy through both vascular damage and increased fibrosis. The predisposing variation in the ATM gene will need to be better defined to optimize it as a predictive marker for assessing radiotherapy late effects.

  1. [Neonatal renal vein thrombosis in a heterozygous carrier of both factor V Leiden and the MTHFR gene mutation].

    PubMed

    Wannes, S; Soua, H; Ghanmi, S; Braham, H; Hassine, M; Hamza, H A; Ben Hamouda, H; Sfar, M-T

    2012-04-01

    Renal vein thrombosis (RVT) is a rare but potentially serious neonatal disease. Its epidemiology and its clinical and biological expression are currently well known, but its etiological exploration, like that of venous thromboembolism, is increasingly complex. Perinatal risk factors such as prematurity, dehydration, and birth asphyxia have lost their direct accountability at the expense of their interaction with constitutional disorders of hemostasis. We report a case of RVT in a newborn who was a heterozygous carrier of both factor V Leiden and the methylene tetrahydrofolate reductase (MTHFR) gene mutation. We recall the clinical and epidemiological characteristics. A search for inborn blood coagulation disorders should be systematic in the newborn infant with venous thrombosis because of the risk of recurrence, taking into account perinatal factors and maternal thrombophilia (especially if RVT is established during the prenatal period). PMID:22361411

  2. One carbon metabolism disturbances and the C677T MTHFR gene polymorphism in children with autism spectrum disorders.

    PubMed

    Paşca, Sergiu P; Dronca, Eleonora; Kaucsár, Tamás; Craciun, Elena C; Endreffy, Emõke; Ferencz, Beatrix K; Iftene, Felicia; Benga, Ileana; Cornean, Rodica; Banerjee, Ruma; Dronca, Maria

    2009-10-01

    Autism spectrum disorders (ASDs), which include the prototypic autistic disorder (AD), Asperger's syndrome (AS) and pervasive developmental disorders not otherwise specified (PDD-NOS), are complex neurodevelopmental conditions of unknown aetiology. The current study investigated the metabolites in the methionine cycle, the transsulphuration pathway, folate, vitamin B(12) and the C677T polymorphism of the MTHFR gene in three groups of children diagnosed with AD (n= 15), AS (n= 5) and PDD-NOS (n= 19) and their age- and sex-matched controls (n= 25). No metabolic disturbances were seen in the AS patients, while in the AD and PDD-NOS groups, lower plasma levels of methionine (P= 0.01 and P= 0.03, respectively) and alpha-aminobutyrate were observed (P= 0.01 and P= 0.001, respectively). Only in the AD group, plasma cysteine (P= 0.02) and total blood glutathione (P= 0.02) were found to be reduced. Although there was a trend towards lower levels of serine, glycine, N, N-dimethylglycine in AD patients, the plasma levels of these metabolites as well as the levels of homocysteine and cystathionine were not statistically different in any of the ASDs groups. The serum levels of vitamin B(12) and folate were in the normal range. The results of the MTHFR gene analysis showed a normal distribution of the C677T polymorphism in children with ASDs, but the frequency of the 677T allele was slightly more prevalent in AD patients. Our study indicates a possible role for the alterations in one carbon metabolism in the pathophysiology of ASDs and provides, for the first time, preliminary evidence for metabolic and genetic differences between clinical subtypes of ASDs. PMID:19267885

  3. Maternal and offspring MTHFR gene C677T polymorphism as predictors of congenital atrial septal defect and patent ductus arteriosus.

    PubMed

    Zhu, Wenli L; Li, Yong; Yan, Liying; Dao, Jingjing; Li, Shuqin

    2006-01-01

    To observe the association of MTHFR gene C677T locus polymorphism with occurrence of congenital heart defects (CHDs), 21 patients with atrial septal defect (ASD), 35 patients with patent ductus arteriosus (PDA), one patient with both conditions combined, and their biological parents were collected as the case group. Another 104 normal individuals and their biological parents without a family history of birth defects were selected as the control group. MTHFR C677T genotypes of each sample were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results showed for the occurrence of ASD, the odds ratio (OR) of TT genotype was 4.08 [95% confidence interval (95% CI) = 1.28-13.24] compared with CT genotype. For the occurrence of PDA, the ORs of TT were 3.44 (95% CI = 0.89-16.13) and 2.38 (95% CI = 0.92-6.14) compared with CC and CT genotypes, respectively. Author as meant? Compared with CC + CT genotype combination, the ORs of TT were 3.95 (95% CI = 1.38-11.44) and 2.60 (95% CI = 1.02-6.36) for ASD and PSD respectively. The results also had sex differences and the statistical significance was only observed in male ASD and female PDA. The ORs of T allele carriers were 2.29 (95% CI = 1.08-4.92) and 1.88 (95% CI = 1.02-3.47) compared with C allele for the occurrences of ASD and PDA respectively. The analysis of parents genotype showed that the OR of TT mothers was 2.31 (95% CI = 0.96-5.59, P < 0.05) compared with (CC + CT) for the occurrence of PDA in offspring. So this study could give a clue that MTHFR C677T locus variation was related with occurrence of ASD and PDA, and the carriers of TT genotype and T allele had higher risk of diseases. The mother carrying TT genotype was associated with occurrence of PDA in offspring. PMID:16373366

  4. Exome resequencing identifies potential tumor-suppressor genes that predispose to colorectal cancer.

    PubMed

    Smith, Christopher G; Naven, Marc; Harris, Rebecca; Colley, James; West, Hannah; Li, Ning; Liu, Yuan; Adams, Richard; Maughan, Timothy S; Nichols, Laura; Kaplan, Richard; Wagner, Michael J; McLeod, Howard L; Cheadle, Jeremy P

    2013-07-01

    Inherited factors account for around one third of all colorectal cancers (CRCs) and include rare high penetrance mutations in APC, MSH2, MSH6, and POLE. Here, we sought novel tumor-suppressor genes that predispose to CRC by exome resequencing 50 sporadic patients with advanced CRC (18 diagnosed ?35 years of age) at a mean coverage of 30×. To help identify potentially pathogenic alleles, we initially sought rare or novel germline truncating mutations in 1,138 genes that were likely to play a role in colorectal tumorigenesis. In total, 32 such mutations were identified and confirmed, and included an insertion in APC and a deletion in POLE, thereby validating our approach for identifying disease alleles. We sought somatic mutations in the corresponding genes in the CRCs of the patients harboring the germline lesions and found biallelic inactivation of FANCM, LAMB4, PTCHD3, LAMC3, and TREX2, potentially implicating these genes as tumor suppressors. We also identified a patient who carried a germline truncating mutation in NOTCH3, part of the Notch signaling cascade that maintains intestinal homeostasis. Our whole exome analyses provided further gene lists to facilitate the identification of potential predisposition alleles. PMID:23585368

  5. A cancer-predisposing "hot spot" mutation of the fumarase gene creates a dominant negative protein.

    PubMed

    Lorenzato, Annalisa; Olivero, Martina; Perro, Mario; Brière, Jean Jacques; Rustin, Pierre; Di Renzo, Maria Flavia

    2008-02-15

    The Fumarase (Fumarate Hydratase, FH) is a tumor suppressor gene whose germline heterozygous mutations predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC). The FH gene encodes an enzyme of the Krebs cycle, functioning as a homotetramer and catalyzing the hydration of fumarate to malate. Among the numerous FH mutations reported so far, the R190H missense mutation is the most frequent in HLRCC patients. Here we show the functional analyses of the R190H, in comparison to the better characterized E319Q mutation. We first expressed wild-type and mutated proteins in FH deficient human skin fibroblasts, using lentiviral vectors. The wild-type transgene was able to restore the FH enzymatic activity in cells, while the R190H- and E319Q-FH were not. More interestingly, when the same transgenes were expressed in normal, FH-proficient cells, only the R190H-FH reduced the endogenous FH enzymatic activity. By enforcing the expression of equal amount of wild-type and R190H-FH in the same cell, we showed that the mutated FH protein directly inhibited enzymatic activity by nearly abrogating the FH homotetramer formation. These data demonstrate the dominant negative effect of the R190H missense mutation in the FH gene and suggest that the FH tumor-suppressing activity might be impaired in cells carrying a heterozygous mutation. PMID:17960613

  6. Influence of Nitrous Oxide Anesthesia, B-Vitamins, and MTHFR gene polymorphisms on Perioperative Cardiac Events: The Vitamins in Nitrous Oxide (VINO) Randomized Trial

    PubMed Central

    Nagele, Peter; Brown, Frank; Francis, Amber; Scott, Mitchell G.; Gage, Brian F.; Miller, J. Philip

    2013-01-01

    Background Nitrous oxide causes an acute increase in plasma homocysteine that is more pronounced in patients with the MTHFR C677T or A1298C gene variant. In this randomized controlled trial we sought to determine if patients carrying the MTHFR C677T or A1298C variant had a higher risk for perioperative cardiac events after nitrous oxide anesthesia and if this risk could be mitigated by B-vitamins. Methods We randomized adult patients with cardiac risk factors undergoing noncardiac surgery to receive nitrous oxide plus intravenous B-vitamins before and after surgery or to nitrous oxide and placebo. Serial cardiac biomarkers and 12-lead electrocardiograms were obtained. The primary study endpoint was the incidence of myocardial injury, as defined by cardiac troponin I elevation within the first 72 hours after surgery. Results A total of 500 patients completed the trial. Patients who were homozygous for either MTHFR C677T or A1298C gene variant (n= 98; 19.6%) had no increased rate of postoperative cardiac troponin I elevation compared to wild-type and heterozygous patients (11.2% vs. 14.0%; relative risk 0.96, 95% CI 0.85 to 1.07, p=0.48). B-vitamins blunted the rise in homocysteine, but had no effect on cardiac troponin I elevation compared to patients receiving placebo (13.2% vs. 13.6%; relative risk 1.02, 95% CI 0.78 to 1.32, p=0.91). Conclusions Neither MTHFR C677T and A1298C gene variant nor acute homocysteine increase are associated with perioperative cardiac troponin elevation after nitrousoxide anesthesia. B-vitamins blunt nitrous oxide-induced homocysteine increase but have no effect on cardiac troponin elevation. PMID:23856660

  7. Association of folate metabolism genes MTHFR and MTRR with multiple complex congenital malformation risk in Chinese population of Shanxi

    PubMed Central

    Zhang, Qin; Bai, Baoling; Liu, Xiaozhen; Miao, Chunyue

    2014-01-01

    Birth defects are common, serious malformations with a complex etiology that suggests involvement of both genetic and environmental factors. Low dietary folate and polymorphisms in genes of folate metabolism can influence risk for birth defects. In the present study 250 Chinese birth defects cases who suffered 1-8 types of birth defect disease phenotypes were subjected and two genetic variants in two folate metabolism key enzymes, rs1801394 of methionine synthase reductase (MTRR) and rs1801133 of methylenetetrahydrofolate reductase (MTHFR) were genotyped by using SNaPshot method. The results indicated that rs1801394 and rs1801133 were associated with multiple birth defects. According to homology of organogenesis, the disease phenotypes were classified into ectoderm-, mesoderm-, and endoderm-developed groups. Genetic analysis results displayed that as protective factors, genetic variants of rs1801133 and rs1801394 were associated with the risk of ectoderm-, and endoderm-developed malformations, but only the variant of rs1801394 was associated with the risk of mesoderm-developed malformations. Our present study first related nutrition metabolism related gene variants to germ layers and provided a novel understanding of an implication of earlier causation of birth defects pathogenesis in humans.

  8. [Genetic variant C677T in the MTHFR in women with recurrent early fetal loss].

    PubMed

    Ivanov, P; Kovacheva, K; Komsa-Penkova, R; Konova, E; Simeonova, M; Popov, I; Gecheva, S; Bozhinova, S; Tanchev, S; Tsafarov, M

    2007-01-01

    The aim of this study was to evaluate correlation of carrier status for thrombophilic gene mutation--C677T in the methylenetetrahydrofolate reductase (MTHFR) and recurrent early pregnancy loss. Recently inherited thrombophilia was discussed as a predisposed factor for early recurrent fetal loss (ERFL). We investigated carrier status for C677T genetic variant in 54 women with ERFL before 10 week of gestation and 67 women with one or more successful pregnancy. It was found significant prevalence of C677T genetic variant in MTHFR in women with ERFL compared with controls (p = 0.005). The significant high prevalence of C677T genetic variant in women with ERFL suggests that thrombophilia have an increased risk of early pregnancy loss and possibly, although the definition of the magnitude of risk will require prospective longitudinal studies. PMID:17974190

  9. Phosphoinositide 3-kinase ? gene mutation predisposes to respiratory infection and airway damage

    PubMed Central

    Angulo, Ivan; Vadas, Oscar; Garçon, Fabien; Banham-Hall, Edward; Plagnol, Vincent; Leahy, Timothy R.; Baxendale, Helen; Coulter, Tanya; Curtis, James; Wu, Changxin; Blake-Palmer, Katherine; Perisic, Olga; Smyth, Deborah; Maes, Mailis; Fiddler, Christine; Juss, Jatinder; Cilliers, Deirdre; Markelj, Gašper; Chandra, Anita; Farmer, George; Kielkowska, Anna; Clark, Jonathan; Kracker, Sven; Debré, Marianne; Picard, Capucine; Pellier, Isabelle; Jabado, Nada; Morris, James A.; Barcenas-Morales, Gabriela; Fischer, Alain; Stephens, Len; Hawkins, Phillip; Barrett, Jeffrey C.; Abinun, Mario; Clatworthy, Menna; Durandy, Anne; Doffinger, Rainer; Chilvers, Edwin; Cant, Andrew J.; Kumararatne, Dinakantha; Okkenhaug, Klaus; Williams, Roger L.; Condliffe, Alison; Nejentsev, Sergey

    2014-01-01

    Genetic mutations cause primary immunodeficiencies (PIDs), which predispose to infections. Here we describe Activated PI3K-? Syndrome (APDS), a PID associated with a dominant gain-of-function mutation E1021K in the p110? protein, the catalytic subunit of phosphoinositide 3-kinase ? (PI3K?), encoded by the PIK3CD gene. We found E1021K in 17 patients from seven unrelated families, but not among 3,346 healthy subjects. APDS was characterized by recurrent respiratory infections, progressive airway damage, lymphopenia, increased circulating transitional B cells, increased IgM and reduced IgG2 levels in serum and impaired vaccine responses. The E1021K mutation enhanced membrane association and kinase activity of p110?. Patient-derived lymphocytes had increased levels of phosphatidylinositol 3,4,5-trisphosphate and phosphorylated AKT protein and were prone to activation-induced cell death. Selective p110? inhibitors IC87114 and GS-1101 reduced the activity of the mutant enzyme in vitro, suggesting a therapeutic approach for patients with APDS. PMID:24136356

  10. Phosphoinositide 3-kinase ? gene mutation predisposes to respiratory infection and airway damage.

    PubMed

    Angulo, Ivan; Vadas, Oscar; Garçon, Fabien; Banham-Hall, Edward; Plagnol, Vincent; Leahy, Timothy R; Baxendale, Helen; Coulter, Tanya; Curtis, James; Wu, Changxin; Blake-Palmer, Katherine; Perisic, Olga; Smyth, Deborah; Maes, Mailis; Fiddler, Christine; Juss, Jatinder; Cilliers, Deirdre; Markelj, Gašper; Chandra, Anita; Farmer, George; Kielkowska, Anna; Clark, Jonathan; Kracker, Sven; Debré, Marianne; Picard, Capucine; Pellier, Isabelle; Jabado, Nada; Morris, James A; Barcenas-Morales, Gabriela; Fischer, Alain; Stephens, Len; Hawkins, Phillip; Barrett, Jeffrey C; Abinun, Mario; Clatworthy, Menna; Durandy, Anne; Doffinger, Rainer; Chilvers, Edwin R; Cant, Andrew J; Kumararatne, Dinakantha; Okkenhaug, Klaus; Williams, Roger L; Condliffe, Alison; Nejentsev, Sergey

    2013-11-15

    Genetic mutations cause primary immunodeficiencies (PIDs) that predispose to infections. Here, we describe activated PI3K-? syndrome (APDS), a PID associated with a dominant gain-of-function mutation in which lysine replaced glutamic acid at residue 1021 (E1021K) in the p110? protein, the catalytic subunit of phosphoinositide 3-kinase ? (PI3K?), encoded by the PIK3CD gene. We found E1021K in 17 patients from seven unrelated families, but not among 3346 healthy subjects. APDS was characterized by recurrent respiratory infections, progressive airway damage, lymphopenia, increased circulating transitional B cells, increased immunoglobulin M, and reduced immunoglobulin G2 levels in serum and impaired vaccine responses. The E1021K mutation enhanced membrane association and kinase activity of p110?. Patient-derived lymphocytes had increased levels of phosphatidylinositol 3,4,5-trisphosphate and phosphorylated AKT protein and were prone to activation-induced cell death. Selective p110? inhibitors IC87114 and GS-1101 reduced the activity of the mutant enzyme in vitro, which suggested a therapeutic approach for patients with APDS. PMID:24136356

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

    PubMed

    Couto, Fábio David; Adorno, Elisângela Vitória; Menezes, Joelma Figueiredo; Moura Neto, José Pereira; Rêgo, Marco Antônio Vasconcelos; Reis, Mitermayer Galvão dos; Gonçalves, Marilda Souza

    2004-01-01

    The C677T polymorphism in the methylenetetrahydrofolate reductase gene (MTHFR) is associated with an increase in total homocysteine serum levels (tHcy), described as a risk factor for cardiovascular disease. Eight hundred forty-three neonates from two different maternity hospitals, one public and another private, in Salvador, Bahia, Brazil were screened for this polymorphism by PCR and RFLP. The T-allele frequency in the total sample was 0.23, and the prevalence rates of heterozygous and homozygous carriers were 36.2% and 5.3%, respectively. The T-allele frequency differed and the T/T genotype was more prevalent at the private maternity hospital. The hemoglobin (Hb) profile was investigated by HPLC in 763 newborns. The frequency of variant Hb was higher at the public than at the private maternity hospital. The association of the C677T polymorphism and the Hb profile was investigated in 683 newborns, showing a relatively high frequency of variant Hbs and the T allele. These data could provide an important basis for further studies focusing on potential risks of vaso-occlusive events in these individuals. PMID:15073633

  12. MTHFR 677TT genotype and disease risk: is there a modulating role for B-vitamins?

    PubMed

    Reilly, R; McNulty, H; Pentieva, K; Strain, J J; Ward, M

    2014-02-01

    Methylenetetrahydrofolate reductase (MTHFR) is a critical folate-metabolising enzyme which requires riboflavin as its co-factor. A common polymorphism (677C?T) in the MTHFR gene results in reduced MTHFR activity in vivo which in turn leads to impaired folate metabolism and elevated homocysteine concentrations. Homozygosity for this polymorphism (TT genotype) is associated with an increased risk of a number of conditions including heart disease and stroke, but there is considerable variability in the extent of excess risk in various reports. The present review will explore the evidence which supports a role for this polymorphism as a risk factor for a number of adverse health outcomes, and the potential modulating roles for B-vitamins in alleviating disease risk. The evidence is convincing in the case which links this polymorphism with hypertension and hypertensive disorders of pregnancy, particularly preeclampsia. Furthermore, elevated blood pressure was found to be highly responsive to riboflavin intervention specifically in individuals with the MTHFR 677TT genotype. Future intervention studies targeted at these genetically predisposed individuals are required to further investigate this novel gene-nutrient interaction. This polymorphism has also been associated with an increased risk of neural tube defects (NTD) and other adverse pregnancy outcomes; however, the evidence in this area has been inconsistent. Preliminary evidence has suggested that there may be a much greater need for women with the MTHFR 677TT genotype to adhere to the specific recommendation of commencing folic acid prior to conception for the prevention of NTD, but this requires further investigation. PMID:24131523

  13. Evidence of Paternal N5, N10 - Methylenetetrahydrofolate Reductase (MTHFR) C677T Gene Polymorphism in Couples with Recurrent Spontaneous Abortions (RSAs) in Kolar District- A South West of India

    PubMed Central

    Vanilla, Shiny; Kotur, Pushpa F; Kutty, Moideen A; Vegi, Pradeep Kumar

    2015-01-01

    Introduction: Recurrent spontaneous abortion (RSA) is a multifactorial clinical obstetrics complication commonly occurring in pregnancy. Many research studies have noted the mutations such as C677T in N5, N10 - Methylenetetrahydrofolate reductase (MTHFR)gene which is regarded as RSA risk factor. This study was carried out to determine the occurrence of frequency of C677T of the MTHFR gene mutations with RSA. Aim: The purpose of present study is to determine the frequency of MTHFR C677T polymorphisms in couples with recurrent pregnancy loss and the impact of paternal polymorphisms of MTHFR C677T in recurrent pregnancy loss in population of couples living in Kolar district of Karnataka with RSA. Design: A total of 15 couples with a history of two or more unexplained RSA were enrolled as subjects in the study and a total of 15 couples with normal reproductive history, having two or more children and no history of miscarriages were enrolled as controls. Materials and Methods: DNA extraction from samples case and control group couples and its quantification by Agarose gel electrophoresis, assessment of DNA purity, MTHFR C 677T gene mutation detection by PCR-RFLP method. Statistical analysis: Carried out by web based online SPSS tool. Results: The frequency of C677T genotype showed homozygous wild type CC (80%), heterozygous CT type (13.3%) and homozygous mutation TT type (6.67%) observed in males. Similarly from female’s homozygous wild type CC (86.6%), heterozygous type (13.3%), and homozygous type mutations TT (0%) was recorded. In couple control groups, we observed homozygous wild type CC (86.6%), heterozygous CT type (13.3%) and homozygous type mutations TT type (0%). Conclusion: We noticed a high frequency of MTHFR specifically T allele associated with paternal side.Therefore, the present study indicated the impact of paternal gene polymorphism of MTHFR C677T on screening in couples with recurrent pregnancy loss. PMID:25859445

  14. Tmem79/Matt is the matted mouse gene and is a predisposing gene for atopic dermatitis in human subjects

    PubMed Central

    Saunders, Sean P.; Goh, Christabelle S.M.; Brown, Sara J.; Palmer, Colin N.A.; Porter, Rebecca M.; Cole, Christian; Campbell, Linda E.; Gierlinski, Marek; Barton, Geoffrey J.; Schneider, Georg; Balmain, Allan; Prescott, Alan R.; Weidinger, Stephan; Baurecht, Hansjörg; Kabesch, Michael; Gieger, Christian; Lee, Young-Ae; Tavendale, Roger; Mukhopadhyay, Somnath; Turner, Stephen W.; Madhok, Vishnu B.; Sullivan, Frank M.; Relton, Caroline; Burn, John; Meggitt, Simon; Smith, Catherine H.; Allen, Michael A.; Barker, Jonathan N.W. N.; Reynolds, Nick J.; Cordell, Heather J.; Irvine, Alan D.; McLean, W.H. Irwin; Sandilands, Aileen; Fallon, Padraic G.

    2013-01-01

    Background Atopic dermatitis (AD) is a major inflammatory condition of the skin caused by inherited skin barrier deficiency, with mutations in the filaggrin gene predisposing to development of AD. Support for barrier deficiency initiating AD came from flaky tail mice, which have a frameshift mutation in Flg and also carry an unknown gene, matted, causing a matted hair phenotype. Objective We sought to identify the matted mutant gene in mice and further define whether mutations in the human gene were associated with AD. Methods A mouse genetics approach was used to separate the matted and Flg mutations to produce congenic single-mutant strains for genetic and immunologic analysis. Next-generation sequencing was used to identify the matted gene. Five independently recruited AD case collections were analyzed to define associations between single nucleotide polymorphisms (SNPs) in the human gene and AD. Results The matted phenotype in flaky tail mice is due to a mutation in the Tmem79/Matt gene, with no expression of the encoded protein mattrin in the skin of mutant mice. Mattft mice spontaneously have dermatitis and atopy caused by a defective skin barrier, with mutant mice having systemic sensitization after cutaneous challenge with house dust mite allergens. Meta-analysis of 4,245 AD cases and 10,558 population-matched control subjects showed that a missense SNP, rs6694514, in the human MATT gene has a small but significant association with AD. Conclusion In mice mutations in Matt cause a defective skin barrier and spontaneous dermatitis and atopy. A common SNP in MATT has an association with AD in human subjects. PMID:24084074

  15. A Common Variant in the FTO Gene Is Associated with Body Mass Index and Predisposes to Childhood and Adult Obesity

    PubMed Central

    Frayling, Timothy M.; Timpson, Nicholas J.; Weedon, Michael N.; Zeggini, Eleftheria; Freathy, Rachel M.; Lindgren, Cecilia M.; Perry, John R. B.; Elliott, Katherine S.; Lango, Hana; Rayner, Nigel W.; Shields, Beverley; Harries, Lorna W.; Barrett, Jeffrey C.; Ellard, Sian; Groves, Christopher J.; Knight, Bridget; Patch, Ann-Marie; Ness, Andrew R.; Ebrahim, Shah; Lawlor, Debbie A.; Ring, Susan M.; Ben-Shlomo, Yoav; Jarvelin, Marjo-Riitta; Sovio, Ulla; Bennett, Amanda J.; Melzer, David; Ferrucci, Luigi; Loos, Ruth J. F.; Barroso, Inês; Wareham, Nicholas J.; Karpe, Fredrik; Owen, Katharine R.; Cardon, Lon R.; Walker, Mark; Hitman, Graham A.; Palmer, Colin N. A.; Doney, Alex S. F.; Morris, Andrew D.; Smith, George Davey; Hattersley, Andrew T.; McCarthy, Mark I.

    2009-01-01

    Obesity is a serious international health problem that increases the risk of several common diseases. The genetic factors predisposing to obesity are poorly understood. A genome-wide search for type 2 diabetes–susceptibility genes identified a common variant in the FTO (fat mass and obesity associated) gene that predisposes to diabetes through an effect on body mass index (BMI). An additive association of the variant with BMI was replicated in 13 cohorts with 38,759 participants. The 16% of adults who are homozygous for the risk allele weighed about 3 kilograms more and had 1.67-fold increased odds of obesity when compared with those not inheriting a risk allele. This association was observed from age 7 years upward and reflects a specific increase in fat mass. PMID:17434869

  16. Study on Environmental Causes and SNPs of MTHFR, MS and CBS Genes Related to Congenital Heart Disease

    PubMed Central

    Liu, Yan; Huang, Peng; Lin, Ning; Sun, Xiaoru; Yu, Rongbin; Zhang, Yuanyuan; Qin, Yuming; Wang, Lijuan

    2015-01-01

    Purpose Congenital heart diseases (CHD) are among the most common birth defects in China. Environmental causes and folate metabolism changes may alter susceptibility to CHD. The aim of this study is to evaluate the relevant risk-factors of children with CHD and their mothers. Methods 138 children with CHD and 207 normal children for controls were recruited. Their mothers were also enlisted in this study and interviewed following a questionnaire about their pregnant history and early pregnancy situation. Five single nucleotide polymorphisms (SNPs) in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MS) and cystathionine β-synthase (CBS) of mothers and children were genotyped. Results There were significant differences in the gender of children, occupation of mothers, family history with CHD, history of abortion, history of adverse pregnancy, early pregnancy health, fetus during pregnancy, pesticide exposure and drug exposure in CHD group and control group ( P < 0.05). Logistic regression analyses showed that after adjustment for above factors, MTHFR rs1801131 were significantly associated with their offspring CHD risk in mothers. Compared with the mothers whose MTHFR were rs1801131 AA and AC genotypes, the mothers who got a mutation of MTHFR rs1801131 CC genotypes had a 267% increase in risk of given birth of a CHD children (OR=3.67,95%CI=1.12-12.05). Meanwhile, MTHFR rs1801131 were significantly associated with CHD susceptibility in children (OR = 1.42, 95% CI = 1.00-2.44 in additive model). Conclusions Besides mothers’ social and fertility characteristics, our results suggested that the genetic variants in folate metabolism pathway might be one of the most related risk-factors of CHD. MTHFR rs1801131 were identified as loci in Chinese population that were involved in CHD. PMID:26035828

  17. MTHFR C677T Gene Polymorphism and Head and Neck Cancer Risk: A Meta-Analysis Based on 23 Publications

    PubMed Central

    Niu, Yu-Ming; Deng, Mo-Hong; Chen, Wen; Zeng, Xian-Tao; Luo, Jie

    2015-01-01

    Objective. Conflicting results on the association between MTHFR polymorphism and head and neck cancer (HNC) risk were reported. We therefore performed a meta-analysis to derive a more precise relationship between MTHFR C677T polymorphism and HNC risk. Methods. Three online databases of PubMed, Embase, and CNKI were researched on the associations between MTHFR C677T polymorphism and HNC risk. Twenty-three published case-control studies involving 4,955 cases and 8,805 controls were collected. Odds ratios (ORs) with 95% confidence interval (CI) were used to evaluate the relationship between MTHFR C677T polymorphism and HNC risk. Sensitivity analysis, cumulative analyses, and publication bias were conducted to validate the strength of the results. Results. Overall, no significant association between MTHFR C677T polymorphism and HNC risk was found in this meta-analysis (T versus C: OR = 1.04, 95% CI = 0.92–1.18; TT versus CC: OR = 1.15, 95% CI = 0.90–1.46; CT versus CC: OR = 1.00, 95% CI = 0.85–1.17; CT + TT versus CC: OR = 1.01, 95% CI = 0.87–1.18; TT versus CC + CT: OR = 1.11, 95% CI = 0.98–1.26). In the subgroup analysis by HWE, ethnicity, study design, cancer location, and negative significant associations were detected in almost all genetic models, except for few significant risks that were found in thyroid cancer. Conclusion. This meta-analysis demonstrates that MTHFR C677T polymorphism may not be a risk factor for the developing of HNC. PMID:25802478

  18. MTHFR and ACE Gene Polymorphisms and Risk of Vascular and Degenerative Dementias in the Elderly

    ERIC Educational Resources Information Center

    Pandey, Pratima; Pradhan, Sunil; Modi, Dinesh Raj; Mittal, Balraj

    2009-01-01

    Focal lacunar infarctions due to cerebral small vessel atherosclerosis or single/multiple large cortical infarcts lead to vascular dementia, and different genes and environmental factors have been implicated in causation or aggravation of the disease. Previous reports suggest that some of the risk factors may be common to both vascular as well as…

  19. MTHFR and ACE Gene Polymorphisms and Risk of Vascular and Degenerative Dementias in the Elderly

    ERIC Educational Resources Information Center

    Pandey, Pratima; Pradhan, Sunil; Modi, Dinesh Raj; Mittal, Balraj

    2009-01-01

    Focal lacunar infarctions due to cerebral small vessel atherosclerosis or single/multiple large cortical infarcts lead to vascular dementia, and different genes and environmental factors have been implicated in causation or aggravation of the disease. Previous reports suggest that some of the risk factors may be common to both vascular as well as…

  20. MTHFR (C677T) polymorphism and PR (PROGINS) mutation as genetic factors for preterm delivery, fetal death and low birth weight: A Northeast Indian population based study

    PubMed Central

    Tiwari, Diptika; Bose, Purabi Deka; Das, Somdatta; Das, Chandana Ray; Datta, Ratul; Bose, Sujoy

    2015-01-01

    Preterm delivery (PTD) is one of the most significant contributors to neonatal mortality, morbidity, and long-term adverse consequences for health; with highest prevalence reported from India. The incidence of PTD is alarmingly very high in Northeast India. The objective of the present study is to evaluate the associative role of MTHFR gene polymorphism and progesterone receptor (PR) gene mutation (PROGINS) in susceptibility to PTD, negative pregnancy outcome and low birth weights (LBW) in Northeast Indian population. Methods A total of 209 PTD cases {extreme preterm (< 28 weeks of gestation, n = 22), very preterm (28–32 weeks of gestation, n = 43) and moderate preterm (32–37 weeks of gestation, n = 144) and 194 term delivery cases were studied for MTHFR C677T polymorphism and PR (PROGINS) gene mutation. Statistical analysis was performed using SPSS software. Results Distribution of MTHFR and PR mutation was higher in PTD cases. Presence of MTHFR C677T polymorphism was significantly associated and resulted in the increased risk of PTD (p < 0.001), negative pregnancy outcome (p < 0.001) and LBW (p = 0.001); more significantly in extreme and very preterm cases. Presence of PR mutation (PROGINS) also resulted in increased risk of PTD and negative pregnancy outcome; but importantly was found to increase the risk of LBW significantly in case of very preterm (p < 0.001) and moderately preterm (p < 0.001) delivery cases. Conclusions Both MTHFR C677T polymorphism and PR (PROGINS) mutation are evident genetic risk factors associated with the susceptibility of PTD, negative pregnancy outcome and LBW. MTHFR C677T may be used as a prognostic marker to stratify subpopulation of pregnancy cases predisposed to PTD; thereby controlling the risks associated with PTD. PMID:25709895

  1. Relationship of MTHFR gene 677C ? T polymorphism, homocysteine, and estimated glomerular filtration rate levels with the risk of new-onset diabetes.

    PubMed

    Qin, Xianhui; Li, Youbao; Yuan, Hui; Xie, Di; Tang, Genfu; Wang, Binyan; Wang, Xiaobin; Xu, Xin; Xu, Xiping; Hou, Fanfan

    2015-02-01

    East Asian patients with diabetes have a higher risk for renal complications and strokes than Europeans. We aimed to evaluate the effect of methylenetetrahydrofolate reductase (MTHFR) gene 677 C ? T polymorphism, which was associated with a higher stroke risk and was common in the Chinese population, as well as homocysteine and estimated glomerular filtration rate (eGFR) levels on the risk of new-onset diabetes (NOD). A total of 2422 subjects without diabetes were followed-up for 7 years. NOD was defined as fasting plasma glucose ? 7.0 mmol/L or self-reported physician diagnosis of diabetes. Compared with subjects with MTHFR 677 CC genotype, those with TT genotype had a higher risk of NOD in females (odds ratio 2.78, 95% confidence interval 1.39-5.56) but not in males (0.80, 0.40-1.61, P for interaction = 0.008). Furthermore, MTHFR 677 C ? T polymorphism was more strongly associated with the risk of NOD among females with higher body mass index (BMI, ? 23 vs <23 kg/m(2), P for interaction = 0.009) or lower high-density lipoprotein-cholesterol (HDL-C, <1.3 vs ? 1.3 mmol/L, P for interaction = 0.015) levels. Hyperhomocysteinemia (? 16 vs <10 ?mol/L) was not significantly associated with NOD in males (0.88, 0.42-1.85) or females (1.52, 0.65-3.57). However, mildly decreased eGFR (<90 vs 90-120 mL/min/1.73 m(2)) was associated with NOD mainly in males (1.96, 1.01-3.78; females, 0.74, 0.32-1.72, P for interaction = 0.134). Females with MTHFR 677 TT genotype had a significantly higher risk of NOD, particularly those with higher BMI or low HDL-C levels. The higher risk of NOD associated with mildly decreased eGFR also warrants more investigation. Our results provide insights into the ethnic differences of diabetic complications between East Asian patients and Europeans. PMID:25700330

  2. The Effectiveness of Pemetrexed Monotherapy Depending on Polymorphisms in TS and MTHFR Genes as Well as Clinical Factors in Advanced NSCLC Patients.

    PubMed

    Kucharczyk, Tomasz; Krawczyk, Paweł; Powrózek, Tomasz; Kowalski, Dariusz M; Ramlau, Rodryg; Kalinka-Warzocha, Ewa; Knetki-Wróblewska, Magdalena; Winiarczyk, Kinga; Krzakowski, Maciej; Milanowski, Janusz

    2016-01-01

    In NSCLC, second-line chemotherapy using pemetrexed or docetaxel has limited efficacy and should be dedicated to selected groups of patients. Pemetrexed is an antifolate compound with the ability to inhibit enzymes (TS, DHFR and GARFT) involved in pyrimidine and purine synthesis. The objective of this study was to evaluate the association between polymorphisms of TS and MHFR genes and clinical outcomes in NSCLC patients treated with pemetrexed monotherapy. DNA was isolated from peripheral blood of 72 non-squamous NSCLC patients treated with pemetrexed. Using PCR and RFLP methods, the variable number of tandem repeats (VNTR), the G > C SNP in these repeats and insertion/deletion polymorphism of TS gene as well as 677C > T SNP in MTHFR gene were analyzed and correlated with disease control rate, progression-free survival and overall survival (OS) of NSCLC patients. Carriers of 2R/3R(G), 3R(C)/3R(G), 3R(G)/3R(G) genotypes showed significantly more frequent early progression than carriers of 2R/2R, 2R/3R(C), 3R(C)/3R(C) genotypes of TS gene (p < 0.05). Among carriers of triple 28 bp tandem repeats (3R) in TS gene and C/C genotype of MTHFR gene a significantly shorter OS was observed (HR = 3.07; p = 0.003). In multivariate analysis, significantly higher risk of death was observed in carriers of both 3R/3R genotype in TS and C/C genotype in 677C > T SNP in MTHFR (HR = 3.85; p < 0.005) as well as in patients with short duration of response to first-line chemotherapy (HR = 2.09; p < 0.005). Results of our study suggested that genetic factors may have a high predictive and prognostic value (even greater than clinical factors) for patients treated with pemetrexed monotherapy. PMID:26277606

  3. MTHFR A1298C and C677T gene polymorphisms and susceptibility to chronic myeloid leukemia in Egypt.

    PubMed

    Aly, Rabab M; Taalab, Mona M; Ghazy, Hayam F

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme regulating the intracellular folate metabolism which plays an important role in carcinogenesis through DNA methylation. We aimed to evaluate the association between MTHFR A1298C and C677T polymorphisms and the risks of chronic myeloid leukemia (CML). Eighty-five patients with CML and a control group containing 100 healthy, age and sex matched individuals were examined for MTHFR C677T and A1298C polymorphisms using polymerase chain reaction-restriction fragment-length (PCR-RFLP) method. The frequency of 677TT genotype in patients with CML was significantly higher compared to controls (OR=2.513, 95% CI: 0.722-4.086, P=0.025). No such association was shown for heterozygous 677CT (OR=1.010, 95% CI: 0.460-2.218, P=0.981). Moreover, for A1298C genotype, a statistically significant higher frequency of 1298CC was also detected in CML patients compared to control group (OR=1.1816, 95% CI: 0.952-3.573, P=0.036), 0.036). No such statistical significance was demonstrable for heterozygote 1298AC (OR=1.046, 95% CI: 0.740-1.759, P=0.092). In addition, patients with joint 677CT/1298AC or 677TT/1298CC genotypes showed an association with increased risk of CML (OR=1.849, 95% CI: 0.935-2.540, P=0.024; OR=1.915, 95% CI: 1.202-3.845, P=0.020 respectively). .A statistically significant increased risk of resistant to therapy was observed with 677CT and 1298AC genotypes (P=0.001, P=0.002 respectively). We conclude that both MTHFR 677TT and 1298CC polymorphisms have been associated with risk of CML and both 677CT and 1298AC genotypes are associated with higher risk of resistant to therapy. PMID:24966971

  4. SYN2 is an autism predisposing gene: loss-of-function mutations alter synaptic vesicle cycling and axon outgrowth.

    PubMed

    Corradi, Anna; Fadda, Manuela; Piton, Amélie; Patry, Lysanne; Marte, Antonella; Rossi, Pia; Cadieux-Dion, Maxime; Gauthier, Julie; Lapointe, Line; Mottron, Laurent; Valtorta, Flavia; Rouleau, Guy A; Fassio, Anna; Benfenati, Fabio; Cossette, Patrick

    2014-01-01

    An increasing number of genes predisposing to autism spectrum disorders (ASDs) has been identified, many of which are implicated in synaptic function. This 'synaptic autism pathway' notably includes disruption of SYN1 that is associated with epilepsy, autism and abnormal behavior in both human and mice models. Synapsins constitute a multigene family of neuron-specific phosphoproteins (SYN1-3) present in the majority of synapses where they are implicated in the regulation of neurotransmitter release and synaptogenesis. Synapsins I and II, the major Syn isoforms in the adult brain, display partially overlapping functions and defects in both isoforms are associated with epilepsy and autistic-like behavior in mice. In this study, we show that nonsense (A94fs199X) and missense (Y236S and G464R) mutations in SYN2 are associated with ASD in humans. The phenotype is apparent in males. Female carriers of SYN2 mutations are unaffected, suggesting that SYN2 is another example of autosomal sex-limited expression in ASD. When expressed in SYN2 ?knockout neurons, wild-type human Syn II fully rescues the SYN2 knockout phenotype, whereas the nonsense mutant is not expressed and the missense mutants are virtually unable to modify the SYN2 knockout phenotype. These results identify for the first time SYN2 ?as a novel predisposing gene for ASD and strengthen the hypothesis that a disturbance of synaptic homeostasis underlies ASD. PMID:23956174

  5. Distribution of alleles of the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism in familial spina bifida.

    PubMed

    Johnson, W G; Stenroos, E S; Heath, S C; Chen, Y; Carroll, R; McKoy, V V; Chatkupt, S; Lehner, T

    1999-12-22

    Spina bifida cystica (SB) is one of the most common and disabling of birth defects. Folic acid supplementation in mothers during the periconceptional period has been shown to prevent more than 70% of neural tube defects (NTD) including SB. However, the mechanism is unknown. We tested a series of multicase SB families in which 224 individuals were genotyped and a group of 215 unrelated unaffected (external) control individuals for association of SB with the T allele of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism that produces a heat-labile enzyme protein. The data were analyzed using first the transmission/disequilibrium test (TDT) and second a modified case-control study design with Monte Carlo sampling methods. No association of SB with the MTHFR T allele was found by either method. Presently, association between SB and the T allele has been found in four studies, a Dutch study, an Irish study, a North American study, and an Italian study. But no association was found in four other studies, a British study, a French study, a Turkish study, and a German study. A California population-based study found only modestly increased risk of SB with this allele that was not significant at the P < 0.05 level. The present study finds no evidence of the association. Only one other study, the German study, has used TDT analysis. The present study is the first to use a modified case-control study design with Monte Carlo sampling methods to test this association. Thus, it appears that the MTHFR T allele is a risk factor for SB in some populations but not others. Major genetic risk factors for folate-related SB remain to be found. PMID:10594879

  6. Distinct effects of folate pathway genes MTHFR and MTHFD1L on ruminative response style: a potential risk mechanism for depression.

    PubMed

    Eszlari, N; Kovacs, D; Petschner, P; Pap, D; Gonda, X; Elliott, R; Anderson, I M; Deakin, J F W; Bagdy, G; Juhasz, G

    2016-01-01

    Alterations in the folate pathway have been related to both major depression and cognitive inflexibility; however, they have not been investigated in the genetic background of ruminative response style, which is a form of perseverative cognition and a risk factor for depression. In the present study, we explored the association of rumination (measured by the Ruminative Responses Scale) with polymorphisms of two distinct folate pathway genes, MTHFR rs1801133 (C677T) and MTHFD1L rs11754661, in a combined European white sample from Budapest, Hungary (n=895) and Manchester, United Kingdom (n=1309). Post hoc analysis investigated whether the association could be replicated in each of the two samples, and the relationship between folate pathway genes, rumination, lifetime depression and Brief Symptom Inventory depression score. Despite its functional effect on folate metabolism, the MTHFR rs1801133 showed no effect on rumination. However, the A allele of MTHFD1L rs11754661 was significantly associated with greater rumination, and this effect was replicated in both the Budapest and Manchester samples. In addition, rumination completely mediated the effects of MTHFD1L rs11754661 on depression phenotypes. These findings suggest that the MTHFD1L gene, and thus the C1-THF synthase enzyme of the folate pathway localized in mitochondria, has an important effect on the pathophysiology of depression through rumination, and maybe via this cognitive intermediate phenotype on other mental and physical disorders. Further research should unravel whether the reversible metabolic effect of MTHFD1L is responsible for increased rumination or other long-term effects on brain development. PMID:26926881

  7. MTHFR C677T and A1298C variant genotypes and the risk of microsatellite instability among Iranian colorectal cancer patients.

    PubMed

    Naghibalhossaini, Fakhraddin; Mokarram, Pooneh; Khalili, Islam; Vasei, Mohammad; Hosseini, Seyed Vahid; Ashktorab, Hassan; Rasti, Mozhgan; Abdollahi, Kourosh

    2010-03-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in the folate metabolic pathway. We aimed to test the hypothesis that C677T and A1298C variants of MTHFR predispose to microsatellite instable (MSI) colorectal cancer. We determined MTHFR genotypes in 175 sporadic colorectal cancer patients and a total of 231 normal controls in Shiraz, Southern Iran. Among the genotypes found in our samples, MTHFR CT and CT+TT were associated with increased risk for CRC incidence [odds ratio (OR)=2.4, 95% confidence interval (95%CI)=1.8-4.4; OR=2.4, 95%CI=1.6-3.6, respectively]. Double heterozygotes 677CT/1298AC and double homozygote 677TT/1298AA and 677CC/1298CC genotypes also showed a significantly increased risk of developing CRC compared with the wild-type 677CC/1298AA genotypes of the controls. Among the 151 tumors tested, 36 (23.8%) were MSI+. MSI was more common in proximal tumors (OR=10.4; 95%CI=3.9-27.8) and in smokers (OR=2.9; 95%CI=1.3-6.7). In a case-control comparison, the MTHFR 677CT+TT genotype was strongly associated with MSI (OR=2.6; 95%CI=1.3-5.3). Hypermethylation of mismatch repair genes was positively related with MSI incidence in these tumor series (P=0.00). Our data suggest that the MTHFR 677CT+TT variant genotype may be a risk factor for MSI+ cancer. PMID:20193847

  8. The Two Main Forms of Histiocytic Sarcoma in the Predisposed Flatcoated Retriever Dog Display Variation in Gene Expression

    PubMed Central

    Boerkamp, Kim M.; van Steenbeek, Frank G.; Penning, Louis C.; Groot Koerkamp, Marian J. A.; van Leenen, Dik; Vos-Loohuis, Manon; Grinwis, Guy C. M.; Rutteman, Gerard R.

    2014-01-01

    Examination of gene functions in specific tumor types improves insight in tumorigenesis and helps design better treatments. Due to the rarity of histiocytic/dendritic cell sarcoma in humans, it is difficult to accrue such knowledge. Therefore, comparative research of these cancers in predisposed dog breeds, such as the Flatcoated retriever, can be of value. Histiocytic sarcoma in the dog can be grouped into a soft tissue- and visceral form. The soft tissue form at first is localized, while the visceral form progresses more quickly to a terminal state, which might be related to variations in gene expression. Microarray analyses were performed on fresh-frozen tissue from Flatcoated retrievers with either soft tissue- or visceral histiocytic sarcoma. Expression differences of ten most significantly differentially expressed genes were validated with quantitative real-time PCR (q PCR) analyses. Q PCR analyses confirmed the significantly aberrant expression of three of the selected genes: C6 was up-regulated; CLEC12A and CCL5 were down-regulated in the visceral histiocytic sarcoma compared to the soft tissue form. The findings of our study indicate that these two forms of histiocytic sarcoma in the dog display a variation in gene expression and warrant analysis of functional changes in the expression of those genes in these rare sarcomas in man. PMID:24886914

  9. Germline variants in the SEMA4A gene predispose to familial colorectal cancer type X

    PubMed Central

    Schulz, Eduard; Klampfl, Petra; Holzapfel, Stefanie; Janecke, Andreas R.; Ulz, Peter; Renner, Wilfried; Kashofer, Karl; Nojima, Satoshi; Leitner, Anita; Zebisch, Armin; Wölfler, Albert; Hofer, Sybille; Gerger, Armin; Lax, Sigurd; Beham-Schmid, Christine; Steinke, Verena; Heitzer, Ellen; Geigl, Jochen B.; Windpassinger, Christian; Hoefler, Gerald; Speicher, Michael R.; Richard Boland, C.; Kumanogoh, Atsushi; Sill, Heinz

    2014-01-01

    Familial colorectal cancer type X (FCCTX) is characterized by clinical features of hereditary non-polyposis colorectal cancer with a yet undefined genetic background. Here we identify the SEMA4A p.Val78Met germline mutation in an Austrian kindred with FCCTX, using an integrative genomics strategy. Compared with wild-type protein, SEMA4AV78M demonstrates significantly increased MAPK/Erk and PI3K/Akt signalling as well as cell cycle progression of SEMA4A-deficient HCT-116 colorectal cancer cells. In a cohort of 53 patients with FCCTX, we depict two further SEMA4A mutations, p.Gly484Ala and p.Ser326Phe and the single-nucleotide polymorphism (SNP) p.Pro682Ser. This SNP is highly associated with the FCCTX phenotype exhibiting increased risk for colorectal cancer (OR 6.79, 95% CI 2.63 to 17.52). Our study shows previously unidentified germline variants in SEMA4A predisposing to FCCTX, which has implications for surveillance strategies of patients and their families. PMID:25307848

  10. Breast cancer risk associated with gene expression and genotype polymorphisms of the folate-metabolizing MTHFR gene: a case-control study in a high altitude Ecuadorian mestizo population.

    PubMed

    López-Cortés, Andrés; Echeverría, Carolina; Oña-Cisneros, Fabián; Sánchez, María Eugenia; Herrera, Camilo; Cabrera-Andrade, Alejandro; Rosales, Felipe; Ortiz, Malena; Paz-Y-Miño, César

    2015-08-01

    Breast cancer (BC) is the leading cause of cancer-related death among women in 2014. Methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and MTR reductase (MTRR) are enzymes that play an important role in folate metabolism. The single nucleotide polymorphisms, MTHFR C677T, A1298C, MTR A2756G, and MTRR A66G, alter plasmatic folate and homocysteine concentrations, causing problems during the repairment, synthesis, and methylation of the genetic material. Therefore, it is essential to know how BC risk is associated with histopathological and immunohistochemical characteristics, genotype polymorphisms, and gene expression in a high altitude Ecuadorian mestizo population. DNA was extracted from 195 healthy and 114 affected women. Genotypes were determined by restriction enzymes and genomic sequencing. mRNA was extracted from 26 glandular breast tissue samples, both from cancerous tissue and healthy tissue adjacent to the tumor. Relative gene expression was determined with the comparative Livak method (2(-??CT)). We found significant association between the rs1801133 (A222V) genotypes and an increased risk of BC development: C/T (odds ratio [OR]?=?1.8; 95 % confidence interval [CI]?=?1.1-3.2; P?=?0.039), T/T (OR?=?2.9; 95 % CI?=?1.2-7.2; P?=?0.025), and C/T?+?T/T (OR?=?1.9; 95 % CI?=?1.1-3.3; P?=?0.019). Regarding relative gene expression, we found significant mRNA subexpression between the combined genotypes C/T?+?T/T (rs1801133) and triple negative breast cancer (TNBC) (P?=?0.034). In brief, the MTHFR gene and its protein could act as potential predictive biomarkers of BC, especially TNBC among the high altitude Ecuadorian mestizo population. PMID:25801246

  11. Heterozygous germ-line mutations in the NBN gene predispose to medulloblastoma in pediatric patients.

    PubMed

    Ciara, El?bieta; Piekutowska-Abramczuk, Dorota; Popowska, Ewa; Grajkowska, Wies?awa; Barszcz, S?awomir; Perek, Danuta; Dembowska-Bagi?ska, Bo?enna; Perek-Polnik, Marta; Kowalewska, Ewa; Czaj?ska, Aneta; Syczewska, Ma?gorzata; Czornak, Kamila; Krajewska-Walasek, Ma?gorzata; Roszkowski, Marcin; Chrzanowska, Krystyna H

    2010-03-01

    The NBN (NBS1) gene belongs to a group of double-strand break repair genes. Mutations in any of these genes cause genome instability syndromes and contribute to carcinogenesis. NBN gene mutations cause increased tumor risk in Nijmegen breakage syndrome (NBS) homozygotes as well as in NBN heterozygotes. NBS patients develop different types of malignancies; among solid tumors, medulloblastoma (MB), an embryonal tumor of the cerebellum, has been reported most frequently. The majority of medulloblastomas occur sporadically, some of them manifest within familial cancer syndromes. Several signaling pathways are known to be engaged in hereditary and sporadic MB. The aim of our study was to identify mutations in selected exons of the NBN gene and to determine the frequency of the most common NBN gene mutations in pediatric patients with different types of medulloblastoma. We screened a total of 104 patients with MB and identified 7 heterozygous carriers (6.7%) of two different germ-line mutations of NBN gene; all of them had classic MB. Our results indicate that heterozygous carriers of the germ-line NBN gene mutations (c.511A>G and c.657_661del5) may exhibit increased susceptibility to developing MB. The risk of medulloblastoma is estimated to be 3.0 (for c.511A>G) and 4.86 (for c.657_661del5) times higher than in the general Polish population (p<0.05). These results suggest that heterozygous NBN germ-line mutations may contribute to the etiology of medulloblastoma. PMID:19908051

  12. MTHFR (677 and 1298) and IL-6-174 G/C genes in pathogenesis of Alzheimer's and vascular dementia and their epistatic interaction.

    PubMed

    Mansoori, Nasim; Tripathi, Manjari; Luthra, Kalpana; Alam, Rizwan; Lakshmy, Ramakrishnan; Sharma, Subhadra; Arulselvi, Subramanyam; Parveen, Shama; Mukhopadhyay, Asok K

    2012-05-01

    Genetic risk factors play an important role in the pathogenesis of Alzheimer disease (AD) and vascular dementia (VaD). In this case-control study, we examined C677T and A1298C (rs1801133 and rs1801131) polymorphism in the methylenetetrahydrofolate reductase (MTHFR) genes and their correlation with plasma levels of homocysteine (Hcy) in AD and VaD cases and evaluated the gene-gene interaction (epistasis) with IL-6-174 G/C (rs1800795). CC genotype was associated with elevated levels of plasma homocysteine (p = 0.004) as compared with genotype AA of rs1801131. In AD, we observed a significant (p = 0.04) association with C alleles of rs1801131. Regression analysis revealed that the presence of both rs1801133 T and rs1800795 C alleles increased the odds of developing AD by 2.5 and VaD by 3.7-fold. While rs1800795 (CC or GC) genotypes alone increased the odds of developing VaD by 2.2-fold, the presence of CC genotype of rs1801131 nullified this effect. The findings support the hypothesis that multiple genes are involved to alter the odds of developing AD and VaD. PMID:22015309

  13. Mutation of genes controlling mRNA metabolism and protein synthesis predisposes to neurodevelopmental disorders.

    PubMed

    Sartor, Francesca; Anderson, Jihan; McCaig, Colin; Miedzybrodzka, Zosia; Müller, Berndt

    2015-12-01

    Brain development is a tightly controlled process that depends upon differentiation and function of neurons to allow for the formation of functional neural networks. Mutation of genes encoding structural proteins is well recognized as causal for neurodevelopmental disorders (NDDs). Recent studies have shown that aberrant gene expression can also lead to disorders of neural development. Here we summarize recent evidence implicating in the aetiology of NDDs mutation of factors acting at the level of mRNA splicing, mRNA nuclear export, translation and mRNA degradation. This highlights the importance of these fundamental processes for human health and affords new strategies and targets for therapeutic intervention. PMID:26614670

  14. [Polymorphic genes of xenobiotic-metabolizing enzymes associated with bronchial asthma in genetically predisposed children].

    PubMed

    Vavilin, V A; Makarova, S I; Liakhovich, V V; Gavalov, S M

    2002-04-01

    The frequencies of the CYP1A1 valine allele, homozygous deletions of GSTM1 and GSTT1, and two point mutations of the NAT2 gene, (C481-->T) and S2 (G590-->A), were compared in healthy children and children having bronchial asthma. The S1 mutation was associated with resistance, and all of the other traits, with predisposition to the disease. In families of patients with diseased progenitors and in those with healthy progenitors, the estimates of the asthma risk were similar. In both groups, parameters of the trait association with the disease depended on passive smoking. At passive smoking, a trend to an overrepresentation (high odds ratio, OR) of the GSTM1 null genotype and S2 mutation of the NAT2 gene was observed, whereas the odds ratio of the GSTT1 null genotype decreased, and those of the CYP1A1 and S1 mutation of the NAT2 gene remained unchanged. The highest OR = 36.25 (P < 0.01) was characteristic of the GSTT1 null genotype in nonsmoking hereditary burdened patients. The results obtained suggest an important role of xenobiotic-metabolizing enzymes in development of bronchial asthma. PMID:12018173

  15. Disturbance of cardiac gene expression and cardiomyocyte structure predisposes Mecp2-null mice to arrhythmias

    PubMed Central

    Hara, Munetsugu; Takahashi, Tomoyuki; Mitsumasu, Chiaki; Igata, Sachiyo; Takano, Makoto; Minami, Tomoko; Yasukawa, Hideo; Okayama, Satoko; Nakamura, Keiichiro; Okabe, Yasunori; Tanaka, Eiichiro; Takemura, Genzou; Kosai, Ken-ichiro; Yamashita, Yushiro; Matsuishi, Toyojiro

    2015-01-01

    Methyl-CpG-binding protein 2 (MeCP2) is an epigenetic regulator of gene expression that is essential for normal brain development. Mutations in MeCP2 lead to disrupted neuronal function and can cause Rett syndrome (RTT), a neurodevelopmental disorder. Previous studies reported cardiac dysfunction, including arrhythmias in both RTT patients and animal models of RTT. In addition, recent studies indicate that MeCP2 may be involved in cardiac development and dysfunction, but its role in the developing and adult heart remains unknown. In this study, we found that Mecp2-null ESCs could differentiate into cardiomyocytes, but the development and further differentiation of cardiovascular progenitors were significantly affected in MeCP2 deficiency. In addition, we revealed that loss of MeCP2 led to dysregulation of endogenous cardiac genes and myocardial structural alterations, although Mecp2-null mice did not exhibit obvious cardiac functional abnormalities. Furthermore, we detected methylation of the CpG islands in the Tbx5 locus, and showed that MeCP2 could target these sequences. Taken together, these results suggest that MeCP2 is an important regulator of the gene-expression program responsible for maintaining normal cardiac development and cardiomyocyte structure. PMID:26073556

  16. Mutations predisposing to breast cancer in 12 candidate genes in breast cancer patients from Poland.

    PubMed

    Cybulski, C; Lubi?ski, J; Woko?orczyk, D; Ku?niak, W; Kashyap, A; Sopik, V; Huzarski, T; Gronwald, J; Byrski, T; Szwiec, M; Jakubowska, A; Górski, B; D?bniak, T; Narod, S A; Akbari, M R

    2015-10-01

    A number of genes other than BRCA1 and BRCA2 have been associated with breast cancer predisposition, and extended genetic testing panels have been proposed. It is of interest to establish the full spectrum of deleterious mutations in women with familial breast cancer.We performed whole-exome sequencing of 144 women with familial breast cancer and negative for 11 Polish founder mutations in BRCA1, CHEK2 and NBS1, and we evaluated the sequences of 12 known breast cancer susceptibility genes. A truncating mutation in a breast cancer gene was detected in 24 of 144 women (17%) with familial breast cancer. A BRCA2 mutation was detected in 12 cases, a (non-founder) BRCA1 mutation was detected in 5 cases, a PALB2 mutation was detected in 4 cases and an ATM mutation was detected in 2 cases. Polish women with familial breast cancer who are negative for founder mutations in BRCA1, CHEK2 and NBS1 should be fully screened for mutations in BRCA1, BRCA2 and PALB2. The PALB2 founder mutation c.509_519delGA should be included in the panel of Polish founder mutations. PMID:25330149

  17. Detection of a Tumor Suppressor Gene Variant Predisposing to Colorectal Cancer in an 18th Century Hungarian Mummy.

    PubMed

    Feldman, Michal; Hershkovitz, Israel; Sklan, Ella H; Kahila Bar-Gal, Gila; Pap, Ildikó; Szikossy, Ildikó; Rosin-Arbesfeld, Rina

    2016-01-01

    Mutations of the Adenomatous polyposis coli (APC) gene are common and strongly associated with the development of colorectal adenomas and carcinomas. While extensively studied in modern populations, reports on visceral tumors in ancient populations are scarce. To the best of our knowledge, genetic characterization of mutations associated with colorectal cancer in ancient specimens has not yet been described. In this study we have sequenced hotspots for mutations in the APC gene isolated from 18th century naturally preserved human Hungarian mummies. While wild type APC sequences were found in two mummies, we discovered the E1317Q missense mutation, known to be a colorectal cancer predisposing mutation, in a large intestine tissue of an 18th century mummy. Our data suggests that this genetic predisposition to cancer already existed in the pre-industrialization era. This study calls for similar investigations of ancient specimens from different periods and geographical locations to be conducted and shared for the purpose of obtaining a larger scale analysis that will shed light on past cancer epidemiology and on cancer evolution. PMID:26863316

  18. Knockout of the TauT Gene Predisposes C57BL/6 Mice to Streptozotocin-Induced Diabetic Nephropathy

    PubMed Central

    Han, Xiaobin; Patters, Andrea B.; Ito, Takashi; Schaffer, Stephen W.; Chesney, Russell W.

    2015-01-01

    Diabetic nephropathy is the leading cause of end stage renal disease in the world. Although tremendous efforts have been made, scientists have yet to identify an ideal animal model that can reproduce the characteristics of human diabetic nephropathy. In this study, we hypothesize that taurine insufficiency is a critical risk factor for development of diabetic nephropathy associated with diabetes mellitus. This hypothesis was tested in vivo in TauT heterozygous (TauT+/-) and homozygous (TauT-/-) knockout in C57BL/6 background mice. We have shown that alteration of the TauT gene (also known as SLC6A6) has a substantial effect on the susceptibility to development of extensive diabetic kidney disease in both TauT+/- and TauT-/-mouse models of diabetes. These animals developed histological changes characteristic of human diabetic nephropathy that included glomerulosclerosis, nodular lesions, arteriosclerosis, arteriolar dilation, and tubulointerstitial fibrosis. Immunohistochemical staining of molecular markers of smooth muscle actin, CD34, Ki67 and collagen IV further confirmed these observations. Our results demonstrated that both homozygous and heterozygous TauT gene deletion predispose C57BL/6 mice to develop end-stage diabetic kidney disease, which closely replicates the pathological features of diabetic nephropathy in human diabetic patients. PMID:25629817

  19. Detection of a Tumor Suppressor Gene Variant Predisposing to Colorectal Cancer in an 18th Century Hungarian Mummy

    PubMed Central

    Feldman, Michal; Hershkovitz, Israel; Sklan, Ella H.; Kahila Bar-Gal, Gila; Pap, Ildikó; Szikossy, Ildikó; Rosin-Arbesfeld, Rina

    2016-01-01

    Mutations of the Adenomatous polyposis coli (APC) gene are common and strongly associated with the development of colorectal adenomas and carcinomas. While extensively studied in modern populations, reports on visceral tumors in ancient populations are scarce. To the best of our knowledge, genetic characterization of mutations associated with colorectal cancer in ancient specimens has not yet been described. In this study we have sequenced hotspots for mutations in the APC gene isolated from 18th century naturally preserved human Hungarian mummies. While wild type APC sequences were found in two mummies, we discovered the E1317Q missense mutation, known to be a colorectal cancer predisposing mutation, in a large intestine tissue of an 18th century mummy. Our data suggests that this genetic predisposition to cancer already existed in the pre-industrialization era. This study calls for similar investigations of ancient specimens from different periods and geographical locations to be conducted and shared for the purpose of obtaining a larger scale analysis that will shed light on past cancer epidemiology and on cancer evolution. PMID:26863316

  20. Lipid Status and Predisposing Genes in Patients with Diabetes Mellitus Type 1 from Various Ethnic Groups.

    PubMed

    Kolesnikova, L I; Kolesnikov, S I; Darenskaya, M A; Grebenkina, L A; Semenova, N V; Osipova, E V; Gnusina, S V; Bardymova, T A

    2015-12-01

    The peculiarities of HLA class II profile and lipid metabolism were examined in Buryat and Russian ethnic groups of patients with diabetes mellitus type 1. The incidence of type 1 haplotypes in HLA class II gene family was lower in Buryats than that in Russians. In comparison with Russians, the course of diabetes mellitus type 1 in Buryat patients was characterized with a lower content of total lipids, triacylglycerols, total cholesterol, and LDL, which probably explains a more favorable course of the disease in Buryat population. PMID:26642791

  1. High Glucose Predisposes Gene Expression and ERK Phosphorylation to Apoptosis and Impaired Glucose-Stimulated Insulin Secretion via the Cytoskeleton

    PubMed Central

    Yeo, Ronne Wee Yeh; Yang, Kaiyuan; Li, GuoDong; Lim, Sai Kiang

    2012-01-01

    Chronic high glucose (HG) inflicts glucotoxicity on vulnerable cell types such as pancreatic ? cells and contributes to insulin resistance and impaired insulin secretion in diabetic patients. To identify HG-induced cellular aberrations that are candidate mediators of glucotoxicity in pancreatic ? cells, we analyzed gene expression in ERoSHK6, a mouse insulin-secreting cell line after chronic HG exposure (six-day exposure to 33.3 mM glucose). Chronic HG exposure which reduced glucose-stimulated insulin secretion (GSIS) increased transcript levels of 185 genes that clustered primarily in 5 processes namely cellular growth and proliferation; cell death; cellular assembly and organization; cell morphology; and cell-to-cell signaling and interaction. The former two were validated by increased apoptosis of ERoSHK6 cells after chronic HG exposure and reaffirmed the vulnerability of ? cells to glucotoxicity. The three remaining processes were partially substantiated by changes in cellular morphology and structure, and instigated an investigation of the cytoskeleton and cell-cell adhesion. These studies revealed a depolymerized actin cytoskeleton that lacked actin stress fibers anchored at vinculin-containing focal adhesion sites as well as loss of E-cadherin-mediated cell-cell adherence after exposure to chronic HG, and were concomitant with constitutive ERK1/2 phosphorylation that was refractory to serum and glucose deprivation. Although inhibition of ERK phosphorylation by PD98059 promoted actin polymerization, it increased apoptosis and GSIS impairment. These findings suggest that ERK phosphorylation is a proximate regulator of cellular processes targeted by chronic HG-induced gene expression and that dynamic actin polymerization and depolymerization is important in ? cell survival and function. Therefore, chronic HG alters gene expression and signal transduction to predispose the cytoskeleton towards apoptosis and GSIS impairment. PMID:23024780

  2. Sex-dependent behavioral effects of Mthfr deficiency and neonatal GABA potentiation in mice.

    PubMed

    Levav-Rabkin, Tamar; Blumkin, Elinor; Galron, Dalia; Golan, Hava M

    2011-01-20

    The methylenetetrahydrofolate reductase (Mthfr) gene and/or abnormal homocysteine-folate metabolism are associated with increased risk for birth defects and neuropsychiatric diseases. In addition, disturbances of the GABAergic system in the brain as well as Mthfr polymorphism are associated with neurodevelopmental disorders such as schizophrenia and autism. In the present study we performed behavioral phenotyping of male and female Mthfr mice (wild type and their heterozygous littermates). The present study addresses two main questions: (1) genetic susceptibility, as examined by effects of Mthfr deficiency on behavior (Experiment 1) and (2) possible gene-drug interactions as expressed by behavioral phenotyping of Mthfr-deficient mice neonatally exposed to the GABA potentiating drug GVG (Experiment 2). Newborn development was slightly influenced by Mthfr genotype per se (Experiment 1); however the gene-drug interaction similarly affected reflex development in both male and female offspring (Experiment 2). Hyperactivity was demonstrated in Mthfr heterozygous male mice (Experiment 1) and due to GVG treatment in both Wt and Mthfr+/- male and female mice (Experiment 2). The gene-environment interaction did not affect anxiety-related behavior of male mice (Experiment 2). In female mice, gene-treatment interactions abolished the reduced anxiety observed due to GVG treatment and Mthfr genotype (Experiment 2). Finally, recognition memory of adult mice was impaired due to genotype, treatment and the gene-treatment combination in a sex-independent manner (Experiment 2). Overall, Mthfr deficiency and/or GABA potentiation differentially affect a spectrum of behaviors in male and female mice. This study is the first to describe behavioral phenotypes due to Mthfr genotype, GVG treatment and the interaction between these two factors. The behavioral outcomes suggest that Mthfr deficiency modulates the effects of GABA potentiating drugs. These findings suggest that future treatment strategies should consider a combination of genotyping with drug regimens. PMID:20813139

  3. A genome-wide search for genes predisposing to manic-depression, assuming autosomal dominant inheritance

    SciTech Connect

    Coon, H.; Jensen, S.; Hoff, M.; Holik, J.; Plaetke, R.; Reimherr, F.; Wender, P.; Leppert, M.; Byerley, W. )

    1993-06-01

    Manic-depressive illness (MDI), also known as [open quotes]bipolar affective disorder[close quotes], is a common and devastating neuropsychiatric illness. Although pivotal biochemical alterations underlying the disease are unknown, results of family, twin, and adoption studies consistently implicate genetic transmission in the pathogenesis of MDI. In order to carry out linkage analysis, the authors ascertained eight moderately sized pedigrees containing multiple cases of the disease. For a four-allele marker mapping at 5 cM from the disease gene, the pedigree sample has >97% power to detect a dominant allele under genetic homogeneity and has >73% power under 20% heterogeneity. To date, the eight pedigrees have been genotyped with 328 polymorphic DNA loci throughout the genome. When autosomal dominant inheritance was assumed, 273 DNA markers gave lod scores <[minus]2.0 at [theta] = .05, and 4 DNA marker loci yielded lod scores >1 (chromosome 5 -- D5S39, D5S43, and D5S62; chromosome 11 -- D11S85). Of the markers giving lod scores >1, only D5S62 continued to show evidence for linkage when the affected-pedigree-member method was used. The D5S62 locus maps to distal 5q, a region containing neurotransmitter-receptor genes for dopamine, norepinephrine, glutamate, and gamma-aminobutyric acid. Although additional work in this region may be warranted, the linkage results should be interpreted as preliminary data, as 68 unaffected individuals are not past the age of risk. 72 refs., 2 tabs.

  4. Association of 677 C>T (rs1801133) and 1298 A>C (rs1801131) Polymorphisms in the MTHFR Gene and Breast Cancer Susceptibility: A Meta-Analysis Based on 57 Individual Studies

    PubMed Central

    Li, Kai; Li, Wusheng; Dong, Xi

    2014-01-01

    Objective The 677 C>T and 1298 A>C polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene have been widely reported and considered to have a significant effect on breast cancer risk, but the results are inconsistent. A meta-analysis based on 57 eligible studies was carried out to clarify the role of MTHFR gene polymorphisms in breast cancer. Methods and Results Eligible articles were identified by searching databases including PubMed, Web of Science, EMBASE, CNKI and CBM for the period up to August 2012. Finally, a total of 57 studies were included in this meta-analysis. Crude ORs with 95% CIs were used to assess the association between the MTHFR polymorphisms and breast cancer risk. The pooled ORs were performed with additive model, dominant model and recessive model, respectively. Subgroup analysis was also performed by ethnicity. The statistical heterogeneity across studies was examined with ?2-based Q-test. A meta-analysis was performed using the Stata 12.0 software. Overall, the 677 C allele was significantly associated with breast cancer risk (OR?=?0.942, 95%CI?=?0.898 to 0.988) when compared with the 677 T allele in the additive model, and the same results were also revealed under other genetic models. Simultaneously, the 1298 A allele was not associated with the breast cancer susceptibility when compared with the 1298 C allele (OR?=?0.993, 95%CI?=?0.978 to 1.009). Furthermore, analyses under the dominant, recessive and the allele contrast model yielded similar results. Conclusions The results of this meta-analysis suggest that 677 C>T polymorphism in the MTHFR gene may contribute to breast cancer development. However, the 1298 A>C polymorphism is not significantly associated with increased risks of breast cancer. PMID:24945727

  5. Common Mutations of the Methylenetetrahydrofolate Reductase (MTHFR) Gene in Non-Syndromic Cleft Lips and Palates Children in North-West of Iran

    PubMed Central

    Abdollahi-Fakhim, Shahin; Asghari Estiar, Mehrdad; Varghaei, Parizad; Alizadeh Sharafi, Mahdi; Sakhinia, Masoud; Sakhinia, Ebrahim

    2015-01-01

    Introduction: Cleft lips and cleft palates are common congenital abnormalities in children. Various chromosomal loci have been suggested to be responsible the development of these abnormalities. The present study was carried out to investigate the association between the suspected genes (methylenetetrahydrofolate reductase [MTHFR] A1298C and C677T) that might contribute into the etiology of these disorders through application of molecular methods. Materials and Methods: This cross-sectional and explanatory study was carried out on a study population of 65 affected children, 130 respective parents and 50 healthy individuals between 2009 and 2012 at Tabriz University of Medical Sciences, IR Iran. After DNA extraction, amplification refractory mutation system–polymerase chain reaction (ARMS-PCR) and restriction fragment length polymorphism (RFLP)-PCR were used respectively to investigate the C677T and A1298C mutations for the MTHFR gene. Results: There was a significant difference in the rates of the C677T mutation when affected patients and their fathers were compared with the control group (odds ratio [OR]=0.44) (OR=0.64). However, there was no significant difference observed in the rate of this mutation between the patients’ mothers and the control group (OR=1.35). In addition, the abnormality rate was higher in patients with the A1298C mutation and their parents, when compared with the control group. This abnormality rate was higher for the affected children and their fathers in comparison with their mothers (Fathers, OR=0.26; Mothers, OR=0.65; Children, OR=0.55). No significant difference was seen in the rate of the polymorphism C677T in its CC, when the affected children and their parents were compared with the control group. However, there was a significant difference in the A1298C mutation. Conclusion: An association was seen between the A1298C mutation and cleft lip and cleft palate abnormalities in Iran. However, there seems to be a stronger relationship between the C67TT mutation and these abnormalities in other countries, which could be explained by racial differences. Moreover, this association was more notable between the affected children and their fathers than their mothers. The findings in this study may be helpful in future studies and screening programs. PMID:25745606

  6. Polymorphism in the Serotonin Receptor 2a (HTR2A) Gene as Possible Predisposal Factor for Aggressive Traits

    PubMed Central

    Banlaki, Zsofia; Elek, Zsuzsanna; Nanasi, Tibor; Szekely, Anna; Nemoda, Zsofia; Sasvari-Szekely, Maria; Ronai, Zsolt

    2015-01-01

    Aggressive manifestations and their consequences are a major issue of mankind, highlighting the need for understanding the contributory factors. Still, aggression-related genetic analyses have so far mainly been conducted on small population subsets such as individuals suffering from a certain psychiatric disorder or a narrow-range age cohort, but no data on the general population is yet available. In the present study, our aim was to identify polymorphisms in genes affecting neurobiological processes that might explain some of the inter-individual variation between aggression levels in the non-clinical Caucasian adult population. 55 single nucleotide polymorphisms (SNP) were simultaneously determined in 887 subjects who also filled out the self-report Buss-Perry Aggression Questionnaire (BPAQ). Single marker association analyses between genotypes and aggression scores indicated a significant role of rs7322347 located in the HTR2A gene encoding serotonin receptor 2a following Bonferroni correction for multiple testing (p = 0.0007) both for males and females. Taking the four BPAQ subscales individually, scores for Hostility, Anger and Physical Aggression showed significant association with rs7322347 T allele in themselves, while no association was found with Verbal Aggression. Of the subscales, relationship with rs7322347 was strongest in the case of Hostility, where statistical significance virtually equaled that observed with the whole BPAQ. In conclusion, this is the first study to our knowledge analyzing SNPs in a wide variety of genes in terms of aggression in a large sample-size non-clinical adult population, also describing a novel candidate polymorphism as predisposal to aggressive traits. PMID:25658328

  7. Association between MTHFR 677C-T polymorphism and alcohol dependence according to Lesch and Babor typology.

    PubMed

    Benyamina, Amine; Saffroy, Raphaël; Blecha, Lisa; Pham, Patrick; Karila, Laurent; Debuire, Brigitte; Lemoine, Antoinette; Reynaud, Michel

    2009-09-01

    Prior studies have associated 677C-T Methylenetetrahydrofolate reductase (MTHFR) gene polymorphism with decreased enzymatic activity and modified homocysteine regulation. This study determines and compares MTHFR 677C-T distribution and examines its consequences on homocysteine metabolism and alcohol dependence in alcoholic patients classified according to the Babor and Lesch typologies. MTHFR TT genotype was more prevalent in AD patients with milder alcohol dependence (Babor type A) and with Lesch type 3, associated with depression. MTHFR TT was also associated with hyperhomocysteinemia. Determining MTHFR 677C-T genotype, folate and vitamin B12 levels could assist physicians in identifying type 3 patients and improve addictions management. PMID:19650814

  8. Homocysteine Level and Mechanisms of Injury in Parkinson's Disease as Related to MTHFR, MTR, and MTHFD1 Genes Polymorphisms and L-Dopa Treatment

    PubMed Central

    Rozycka, Agata; Jagodzinski, Pawel P.; Kozubski, Wojciech; Lianeri, Margarita; Dorszewska, Jolanta

    2013-01-01

    An elevated concentration of total homocysteine (tHcy) in plasma and cerebrospinal fluid is considered to be a risk factor for Alzheimer's disease (AD) and Parkinson's disease (PD). Homocysteine (Hcy) levels are influenced by folate concentrations and numerous genetic factors through the folate cycle, however, their role in the pathogenesis of PD remains controversial. Hcy exerts a neurotoxic action and may participate in the mechanisms of neurodegeneration, such as excitotoxicity, oxidative stress, calcium accumulation, and apoptosis. Elevated Hcy levels can lead to prooxidative activity, most probably through direct interaction with N-methyl-D-aspartate (NMDA) receptors and sensitization of dopaminergic neurons to age-related dysfunction and death. Several studies have shown that higher concentration of Hcy in PD is related to long-term administration of levodopa (L-dopa). An elevation of plasma tHcy levels can also reflect deficiencies of cofactors in remethylation of Hcy to methionine (Met) (folates and vitamin B12) and in its transsulfuration to cysteine (Cys) (vitamin B6). It is believed that the increase in the concentration of Hcy in PD can affect genetic polymorphisms of the folate metabolic pathway genes, such as MTHFR (C677T, A1298C and G1793A), MTR (A2756G), and MTHFD1 (G1958A), whose frequencies tend to increase in PD patients, as well as the reduced concentration of B vitamins. In PD, increased levels of Hcy may lead to dementia, depression and progression of the disease. PMID:24532985

  9. Polymorphism of Alcohol Metabolizing Gene ADH3 Predisposes to Development of Alcoholic Pancreatitis in North Indian Population

    PubMed Central

    Singh, Divya; Negi, Tajwar S.; Upadhyay, Ghanshyam; Choudhuri, Gourdas

    2015-01-01

    Background and aim: Genetic factors regulating alcohol metabolism could predispose in developing alcoholic pancreatitis (ACP). Studies revealed that alcohol could be metabolized by both ways, oxidative and non-oxidative. The main oxidative pathway includes alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and cytochrome P450 enzyme. We investigated the association of polymorphisms in these enzymes with the alcoholic pancreatitis in the north Indian population. Method: Patients with alcoholic pancreatitis (ACP; n = 72), tropical calcific pancreatitis (TCP; n = 75), alcoholic controls (AC; n = 40), and healthy controls (HC; n = 100) were included in the study. Blood samples were collected from the subjects in EDTA coated vials. DNA was extracted and genotyping for ADH3, ALDH2, and CYP2E1 was done by PCR-RFLP (polymerase chain reaction—restriction fragment length polymorphism). The products were analyzed by gel electrophoresis. Result: The frequency distribution of ADH3*1/*1 genotype was significantly higher in ACP group (59.7%) compared with TCP (38.7%), HC (42%), and AC (37.5%) and was found to be associated with increased risk of alcoholic pancreatitis. There was no statistically significant difference between the frequency distribution of ADH3*1/*1, ADH3*1/*2, and ADH3*2/*2 genotypes between TCP and HC or healthy alcoholics. ALDH2 gene was monomorphic in our population, and the frequencies for CYP2E1 intron 6 Dra I polymorphism were comparable in all the four groups. Conclusion: This study shows that carriers of ADH3*1/*1 individuals consuming alcohol are at higher risk for alcoholic pancreatitis than those with other genotypes such as ADH3*1/*2 and ADH3*2/*2. PMID:26734614

  10. Association between Hcy levels and the CBS844ins68 and MTHFR C677T polymorphisms with essential hypertension

    PubMed Central

    CAI, WEIJUAN; YIN, LIANG; YANG, FANG; ZHANG, LEI; CHENG, JIANG

    2014-01-01

    The aim of the present study was to investigate the association between the homocysteine (Hcy) levels and polymorphisms of the CBS844ins68 and MTHFR C677T genes in essential hypertension (EH). The effects of the MTHFR C677T and CBS844ins68 haploid genotypes and the combined genotypes on EH and levels of Hcy were further explored. The polymorphisms of CBS844ins68 and MTHFR C677T genes in 200 EH and 200 normal tensive (NT) patients were detected using polymerase chain reaction-restriction fragment length polymorphism and analysis of the distribution of genotypes. An automated biochemical analyzer was used to measure the plasma Hcy levels and the clinical biochemistry data. The plasma Hcy levels in EH were significantly higher than those of the NT group (P<0.05). There were no significant differences (P>0.05) between males and females. Two genotypes, deletion/deletion (DD) and deletion/insertion (DI), of the CBS844ins68 polymorphism were found in two groups with no clear differences in two genotypes and allele frequency distribution (P>0.05). There were significant differences in the three genotype frequencies (?2=6.658, ?2=4.410, P<0.05) for MTHFR C677T locus genotypes CC, CT and TT. The Hcy levels in genotypes DD and DI had no significant differences (P>0.05) and the CT and TT types were significantly higher compared to the CC genotype (P<0.05). The CC/DD combined genotype in the two groups was significantly different (P<0.05), and the odds ratio (OR), 0.569 showed that the CC/DD genotype may be a protective factor of hypertension. In the two groups, the Hcy levels for combined genotypes CC/DD, CT/DD, TT/DD and TT/DI were significantly different (P<0.05). The SHEsis software analysis linkage disequilibrium coefficient=0.216, indicates that there is probably a weak linkage for MTHFR C677T and CBS844ins68. Haplotype analysis suggested that the C-D haplotype was negatively correlated with EH (OR, 0.727) and that there was a positive correlation between T-D haplotype and EH (OR, 1.376). MTHFR C677T and CBS844ins68 polymorphisms were present in the populations studied and the CBS844ins68 homozygous mutation was not present. Therefore, there is a correlation between the polymorphisms of the MTHFR C677T gene and EH, and allele T may be one of the predisposing factors. MTHFR C677T and CBS844ins68 may exist with a certain linkage and the T-D haplotype may be a risk factor for EH. PMID:25279160

  11. Association between Hcy levels and the CBS844ins68 and MTHFR C677T polymorphisms with essential hypertension.

    PubMed

    Cai, Weijuan; Yin, Liang; Yang, Fang; Zhang, Lei; Cheng, Jiang

    2014-11-01

    The aim of the present study was to investigate the association between the homocysteine (Hcy) levels and polymorphisms of the CBS844ins68 and MTHFR C677T genes in essential hypertension (EH). The effects of the MTHFR C677T and CBS844ins68 haploid genotypes and the combined genotypes on EH and levels of Hcy were further explored. The polymorphisms of CBS844ins68 and MTHFR C677T genes in 200 EH and 200 normal tensive (NT) patients were detected using polymerase chain reaction-restriction fragment length polymorphism and analysis of the distribution of genotypes. An automated biochemical analyzer was used to measure the plasma Hcy levels and the clinical biochemistry data. The plasma Hcy levels in EH were significantly higher than those of the NT group (P<0.05). There were no significant differences (P>0.05) between males and females. Two genotypes, deletion/deletion (DD) and deletion/insertion (DI), of the CBS844ins68 polymorphism were found in two groups with no clear differences in two genotypes and allele frequency distribution (P>0.05). There were significant differences in the three genotype frequencies (?(2)=6.658, ?(2)=4.410, P<0.05) for MTHFR C677T locus genotypes CC, CT and TT. The Hcy levels in genotypes DD and DI had no significant differences (P>0.05) and the CT and TT types were significantly higher compared to the CC genotype (P<0.05). The CC/DD combined genotype in the two groups was significantly different (P<0.05), and the odds ratio (OR), 0.569 showed that the CC/DD genotype may be a protective factor of hypertension. In the two groups, the Hcy levels for combined genotypes CC/DD, CT/DD, TT/DD and TT/DI were significantly different (P<0.05). The SHEsis software analysis linkage disequilibrium coefficient=0.216, indicates that there is probably a weak linkage for MTHFR C677T and CBS844ins68. Haplotype analysis suggested that the C-D haplotype was negatively correlated with EH (OR, 0.727) and that there was a positive correlation between T-D haplotype and EH (OR, 1.376). MTHFR C677T and CBS844ins68 polymorphisms were present in the populations studied and the CBS844ins68 homozygous mutation was not present. Therefore, there is a correlation between the polymorphisms of the MTHFR C677T gene and EH, and allele T may be one of the predisposing factors. MTHFR C677T and CBS844ins68 may exist with a certain linkage and the T-D haplotype may be a risk factor for EH. PMID:25279160

  12. Retinal Ganglion Cell Loss and Mild Vasculopathy in Methylene Tetrahydrofolate Reductase (Mthfr)-Deficient Mice: A Model of Mild Hyperhomocysteinemia

    PubMed Central

    Markand, Shanu; Saul, Alan; Roon, Penny; Prasad, Puttur; Martin, Pamela; Rozen, Rima; Ganapathy, Vadivel; Smith, Sylvia B.

    2015-01-01

    Purpose. Methylenetetrahydrofolate reductase (Mthfr) is a key enzyme in homocysteine-methionine metabolism. We investigated Mthfr expression in retina and asked whether mild hyperhomocysteinemia, due to Mthfr deficiency, alters retinal neurovascular structure and function. Methods. Expression of Mthfr was investigated at the gene and protein level using quantitative (q) RT-PCR, in situ hybridization, immunoblotting, and immunohistochemistry (IHC). The Mthfr+/+ and Mthfr+/? mice were subjected to comprehensive evaluation using ERG, funduscopy, fluorescein angiography (FA), spectral-domain optical coherence tomography (SD-OCT), HPLC, and morphometric and IHC analysis of glial fibrillary acidic protein (GFAP) at 8 to 24 weeks. Results. Gene and protein analyses disclosed widespread retinal expression of Mthfr. Electroretinography (ERG) revealed a significant decrease in positive scotopic threshold response in retinas of Mthfr+/? mice at 24 weeks. Fundus examination in mice from both groups was normal; FA revealed areas of focal vascular leakage in 20% of Mthfr+/? mice at 12 to 16 weeks and 60% by 24 weeks. The SD-OCT revealed a significant decrease in nerve fiber layer (NFL) thickness at 24 weeks in Mthfr+/? compared to Mthfr+/+ mice. There was a 2-fold elevation in retinal hcy at 24 weeks in Mthfr+/? mice by HPLC and IHC. Morphometric analysis revealed an approximately 20% reduction in cells in the ganglion cell layer of Mthfr+/? mice at 24 weeks. The IHC indicated significantly increased GFAP labeling suggestive of Müller cell activation. Conclusions. Mildly hyperhomocysteinemic Mthfr+/? mice demonstrate reduced ganglion cell function, thinner NFL, and mild vasculopathy by 24 weeks. The retinal phenotype is similar to that of hyperhomocysteinemic mice with deficiency of cystathionine-?-synthase (Cbs) reported earlier. The data support the hypothesis that hyperhomocysteinemia may be causative in certain retinal neurovasculopathies. PMID:25766590

  13. Prospective study of MTHFR genetic polymorphisms as a possible etiology of male infertility.

    PubMed

    Li, S-S; Li, J; Xiao, Z; Ren, A-G; Jin, L

    2014-01-01

    The aim of this study was to explore the relationship between 2 genetic polymorphisms of the methylenetetrahydrofolate reductase gene (MTHFR), C677T and A1298C, and determine the long-term reproductive outcome in infertile men. This was a prospective study conducted in an andrology clinic. Men with a 1-year history of infertility were assessed for the MTHFR polymorphisms at a 5-year follow-up. We compared the MTHFR C677T and A1298C polymorphisms by polymerase chain reaction-restriction fragment length polymorphism between men who did and did not bear children during follow-up. Of the 215 men who were infertile at 1 year, 82 (38.1%) remained infertile and 133 (61.9%) achieved natural conception during the 5-year follow-up, with the highest rate in the first year (32.6%). The MTHFR 677TT genotype (homozygote) was associated with a substantially increased risk of infertility during follow-up [odds ratio (OR) = 10.242; 95% confidence interval (CI) = 1.257-83.464] relative to the MTHFR 677CC genotype (wild-type). Risk of infertility was not increased by the MTHFR A1298C polymorphism alone, but was increased by the combination of polymorphisms MTHFR C677T and MTHFR A1298C (OR = 11.818; 95%CI = 1.415-98.674). The homozygous MTHFR C677T genotype was a risk factor for male infertility during 5-year follow-up, whereas a correlation between MTHFR A1298C and infertility was not observed. The MTHFR C677T and MTHFR A1298C polymorphisms had additive effects on male infertility. PMID:24737513

  14. Ethnic variation of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate-reductase (MTHFR) gene in southwestern Mexico.

    PubMed

    Antonio-Véjar, V; Del Moral-Hernández, O; Alarcón-Romero, L C; Flores-Alfaro, E; Leyva-Vázquez, M A; Hernández-Sotelo, D; Illades-Aguiar, B

    2014-01-01

    In this study, we examined the distribution of genotype and allele frequencies of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate-reductase gene (MTHFR) in two ethnic groups in the State of Guerrero, Mexico, which were compared with those of the Mestizo population of the region. A comparative study was conducted on 455 women from two ethnic groups and a group of Mestizo women of the State of Guerrero, Mexico: 135 Nahuas, 124 Mixtecas, and 196 Mestizas. Genotyping of both polymorphisms were performed by using polymerase chain reaction-restriction fragment length polymorphism methods. We found that the 677TT genotype was more frequent in Nahua and Mixteca women compared to Mestiza women (P = 0.008), and the most prevalent genotype in both ethnic groups was the 1298AA genotype (P < 0.001). We also compared the 677T allele frequency obtained from the groups studied with the frequencies reported in other ethnic groups of Mexico (Huichol, Tarahumara, and Purepecha). There were significant differences between the three ethnic groups compared to Nahuas (Huicholes, P = 0.004; Tarahumaras, P < 0.001; Purepechas, P = 0.042). Our results indicated significant differences in the frequencies of the C677T and A1298C polymorphisms between the two ethnic groups and the Mestizo population of the State of Guerrero. In addition, we found strong differences with other ethnic groups in Mexico. These results could be useful for future studies investigating diseases related to folate metabolism, and could help the government to design specific nutrition programs for different ethnic groups. PMID:25299110

  15. Association between MTHFR gene polymorphisms (C677T, A1298C) and genetic susceptibility to prostate cancer: a meta-analysis.

    PubMed

    Chen, P L; Li, W T; Wang, J; Jiang, Y D; Wu, P; Chen, T; Zheng, S B

    2015-01-01

    Genetic polymorphisms (C677T and A1298C) in methylenetetrahydrofolate reductase (MTHFR) were shown to be related to prostate cancer risk in previous studies; however, the results are controversial. We performed a meta-analysis of previous studies and quantitatively estimated these associations. Pubmed, Embase, and Cochrane Library Database were searched for published case-control studies evaluating the association between C677T (or A1298C) and prostate cancer risk. Pooled associations were presented as odds ratios (ORs) along with their 95% confidence intervals. Twenty-one case control studies were identified for meta-analysis that included 21,581 participants. No significant associations were found between the MTHFR polymorphisms C677T or A1298C and prostate cancer risk in our meta-analysis. However, in subgroup analyses, the C677T CT polymorphism was associated with increased prostate cancer risk in East Asians (CT vs CC+TT: OR = 1.324, P = 0.03). The A1298C CC polymorphism in MTHFR was also linked to slightly reduced prostate cancer risk in European residents (CC vs AC+AA: OR = 0.751, P = 0.004; CC vs AA: OR = 0.768, P = 0.011), whereas it was associated with a significantly increased prostate cancer risk in Asian residents (CC vs AA: OR = 1.862, P = 0.006). The C677T CT polymorphism of MTHFR may be a risk factor for prostate cancer in East Asians. The association between the MTHFR A1298C CC genotype and prostate cancer risk may vary within different populations. Large-scale well-designed studies are required to confirm these associations. PMID:26782572

  16. Meta-analysis of Methylenetetrahydrofolate reductase maternal gene in Down syndrome: increased susceptibility in women carriers of the MTHFR 677T allele.

    PubMed

    Victorino, D B; Godoy, M F; Goloni-Bertollo, E M; Pavarino, E C

    2014-08-01

    Because a number of data studies include some controversial results about Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and Down syndrome (DS), we performed a meta-analysis to determine a more precise estimation of this association. Studies were searched on PubMed, EMBASE and Lilacs-Scielo, up to April 2013, and they were eligible if they included case mothers (DSM) that have gave birth to children with DS, and controls mothers (CM) that have gave birth to healthy children without chromosomal abnormality, syndrome or malformation. The combined odds ratio with 95% confidence intervals was calculated by fixed or random effects models to assess the strength of associations. Potential sources of heterogeneity between studies were evaluated using Q test and the I(2). Publication bias was estimated using Begg's test and Egger's linear regression test. Sensitivity analyses were performed by using allelic, dominant, recessive and codominant genetic models, Hardy-Weinberg equilibrium (HWE) and ethnicity. Twenty-two studies with 2,223 DSM and 2,807 CM were included for MTHFR C677T and 15 studies with 1,601 DSM and 1,849 CM were included for MTHFR A1298C. Overall analysis suggests an association of the MTHFR C677T polymorphism with maternal risk for DS. Moreover, no association between the MTHFR A1298C polymorphism and maternal risk for DS was found. There is also evidence of higher heterogeneity, with I(2) test values ranging from 8 to 89%. No evidence of publication bias was found. Taken together, our meta-analysis implied that the T allele carriers might carry an increased maternal risk for DS. PMID:24913031

  17. Increased susceptibility to mild neonatal stress in MTHFR deficient mice.

    PubMed

    Kezurer, N; Galron, D; Golan, H M

    2013-09-15

    Early life stress is shown to have a life-span outcome on human and animal behavior, increasing the risk for psychopathology. The gene methylenetetrahydrofolate reductase (MTHFR), which encodes for a key enzyme in one carbon metabolism, shows a high prevalence of polymorphism in patients with developmental disorders. Here we examined the hypothesis that MTHFR deficiency results in an increased susceptibility of the developing brain to mild neonatal stress (NS). Mild NS failed to alter corticosterone levels in young and adult Wt mice. However, an elevated level of corticosterone was found in the MTHFR deficient-NS female, exemplifying enhanced sensitivity to NS. Behavioral phenotyping of Wt and MTHFR deficient mice provides evidence that the effect of mild NS may be amplified by the MTHFR deficient genotype. Distinct behavioral characteristics were altered in male and female mice. In general, three patterns of influence on mice behavior were observed: (1) an additive suppressive effect of NS and MTHFR deficiency on exploration and activity was evident in females; (2) stress related parameters were significantly sensitive to genotype in females, presenting an interaction between genotype and sex; (3) various aspects of behavior in a social setting were modified preferably in males by genotype, NS and the interaction between the two, while females exhibited a smaller effect that was restricted to NS with no genotype effect. Overall, our results support an interaction between mild NS, the MTHFR genotype and sex. We suggest using this animal model to study the molecular mechanism linking these two risk factors and their involvement in neurodevelopmental disorders such as schizophrenia and autism. PMID:23896051

  18. Interaction of homocysteine and conventional predisposing factors on risk of ischaemic stroke in young people: consistency in phenotype?disease analysis and genotype?disease analysis

    PubMed Central

    Pezzini, A; Grassi, M; Del Zotto, E; Assanelli, D; Archetti, S; Negrini, R; Caimi, L; Padovani, A

    2006-01-01

    Background and objectives Whether the association between mild hyperhomocysteinaemia and ischaemic stroke is the consequence of a predisposing genetic background or is due to the confounding influence of established predisposing factors remains to be determined. Methods Plasma total homocysteine (tHcy) concentration and the distribution of the C677T genotypes of the methylenetetrahydrofolate reductase gene (MTHFR) were compared in 174 consecutive patients with stroke aged <45?years and 155 age and sex?matched controls. The effect of conventional risk factors on the relationship between phenotype?disease and genotype?disease was analysed by two?way and three?way interaction analysis and by the classification and regression trees (CART) model. Results tHcy concentrations were markedly higher in patients with ischaemic stroke (median 11.9??mol/l, range 2.0–94.0) than in controls (median 9.8??mol/l, range 4.7–49.6). An increased risk was also associated with the TT677 genotype (odds ratio (OR) 1.98; 95% confidence interval (CI) 1.04 to 3.78) and with the T allele (1.40; 95% 1.03 to 1.92) of the MTHFR gene. A differential effect of Hcy levels on risk of stroke was observed according to the distribution of environmental–behavioural risk factors, with a stronger influence in the subcategory of people with hypertension and smokers (OR 24.8; 95% CI 3.15 to 196). A comparable environmental?dependent TT677 MTHFR genotype–stroke association was observed in the genotype?disease analysis. Conclusions A consistency of phenotype?disease analysis and genotype?disease analysis is indicated by analysing specific subcategories of patients, defined by the distribution of established risk factors. The assumption that the Hcy–stroke relationship is unlikely due to a reverse?causality bias is indirectly supported by our data. PMID:16624841

  19. Factors Predisposing Drug Abuse.

    ERIC Educational Resources Information Center

    Cheney, Carl D.; Phelps, Brady J.

    The exact nature of the events which may predispose a person to substance abuse is not known. This paper provides a theoretical discussion and review which emphasizes three contexts which have been shown to predispose on individual to drug abuse: (1) prenatal exposure to a given substance; (2) environmental conditions present upon first exposure…

  20. Geographical Distribution of MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in China: Findings from 15357 Adults of Han Nationality

    PubMed Central

    Yang, Boyi; Liu, Yuyan; Li, Yongfang; Fan, Shujun; Zhi, Xueyuan; Lu, Xiangxiang; Wang, Da; Zheng, Quanmei; Wang, Yinuo; Wang, Yanxun; Sun, Guifan

    2013-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms are important genetic determinants for homocysteine (Hcy) levels, and are associated with several disorders. These polymorphisms are heterogeneously distributed worldwide. Our objective was to explore the geographical distributions of these polymorphisms in China. Methodologies 15357 healthy adults were recruited from 10 regions. Buccal samples were collected and genomic DNA was isolated. Genotyping was performed using the fluorogenic 5?-nuclease assay. Principal Findings The prevalence of the three polymorphisms among different populations from China varied significantly and showed apparent geographical gradients. For MTHFR C677T, the frequencies of the 677T allele and the 677TT genotype were significantly higher among northern populations and ranged from the lowest values (24.0% and 6.4%, respectively) in Hainan (southern) to the highest values (63.1% and 40.8%, respectively) in Shandong (northern). For MTHFR A1298C, the 1298C allele and the 1298CC genotype frequencies were significantly higher among southern populations and increased from low values (13.1% and 1.4%, respectively) in Shandong to high values (25.7% and 6.7%, respectively) in Hainan. For A66G, the 66G allele and the 66GG genotype frequencies increased from lower values (23.7% and 5.4%, respectively) in Shandong to higher values (29.2% and 8.6%, respectively) in Hainan. The overall frequency of the 677T allele, 677TT genotype, 1298C allele, 1298CC genotype, 66G allele and 66GG genotype in the Chinese Han population was 45.2%, 23.2%, 18.6%, 3.9%, 25.7%, and 6.6%, respectively. No gender differences were found in the prevalence of both the MTHFR C677T and MTRR A66G polymorphisms. Conclusions This study indicates that there are marked geographical variations in the prevalence of the three polymorphisms among Chinese Han populations. Our baseline data may be useful for future researches in related fields. PMID:23472119

  1. A case report of two male siblings with autism and duplication of Xq13-q21, a region including three genes predisposing for autism.

    PubMed

    Wentz, Elisabet; Vujic, Mihailo; Kärrstedt, Ewa-Lotta; Erlandsson, Anna; Gillberg, Christopher

    2014-05-01

    Autism spectrum disorder, severe behaviour problems and duplication of the Xq12 to Xq13 region have recently been described in three male relatives. To describe the psychiatric comorbidity and dysmorphic features, including craniosynostosis, of two male siblings with autism and duplication of the Xq13 to Xq21 region, and attempt to narrow down the number of duplicated genes proposed to be leading to global developmental delay and autism. We performed DNA sequencing of certain exons of the TWIST1 gene, the FGFR2 gene and the FGFR3 gene. We also performed microarray analysis of the DNA. In addition to autism, the two male siblings exhibited severe learning disability, self-injurious behaviour, temper tantrums and hyperactivity, and had no communicative language. Chromosomal analyses were normal. Neither of the two siblings showed mutations of the sequenced exons known to produce craniosynostosis. The microarray analysis detected an extra copy of a region on the long arm of chromosome X, chromosome band Xq13.1-q21.1. Comparison of our two cases with previously described patients allowed us to identify three genes predisposing for autism in the duplicated chromosomal region. Sagittal craniosynostosis is also a new finding linked to the duplication. PMID:23974867

  2. MTHFR gene polymorphism in acute lymphoblastic leukemia among North Indian children: a case-control study and meta-analysis updated from 2011.

    PubMed

    Roy Moulik, Nirmalya; Parveen, Farah; Kumar, Archana; Awasthi, Shally; Agrawal, Suraksha

    2014-07-01

    Studies on the association of methylenetetrahydrofolate reductase (MTHFR) genotype in childhood acute lymphoblastic leukemia (ALL) have yielded conflicting results. The present study examines this association in north Indian children with ALL and includes an updated meta-analysis. MTHFR (677 and 1298) genotype of children with ALL and healthy adult controls were done by the PCR-restriction fragment length polymorphism (PCR-RFLP) method and were compared using various models of inheritance. A total of 150 patients and 300 controls were included. The 677T allele was found protective (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.04-0.94), whereas 1298C allele led to an increase in risk (OR 4.44, 95% CI 2.19-8.99) of childhood ALL. Meta-analysis included 31 and 27 studies examining the association of 677 and 1298 genotypes, respectively. The 677 C -> T polymorphism was protective (OR 0.90, 95% CI 0.82-0.99). Protection was more pronounced in folate-sufficient populations as compared with those not covered by folate fortification guidelines. The 1298A->C polymorphism was associated with a marginal increase in risk (OR 1.19, 95% CI 1.01-1.40). PMID:24919644

  3. Genetic variants in 3?-UTRs of methylenetetrahydrofolate reductase (MTHFR) predict colorectal cancer susceptibility in Koreans

    PubMed Central

    Joo Jeon, Young; Woo Kim, Jong; Mi Park, Hye; Kim, Jung O; Geun Jang, Hyo; Oh, Jisu; Gyu Hwang, Seong; Won Kwon, Sung; Oh, Doyeun; Keun Kim, Nam

    2015-01-01

    Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3?-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3?-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3?-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention. PMID:26046315

  4. Genetic variants in 3'-UTRs of methylenetetrahydrofolate reductase (MTHFR) predict colorectal cancer susceptibility in Koreans.

    PubMed

    Joo Jeon, Young; Woo Kim, Jong; Mi Park, Hye; Kim, Jung O; Geun Jang, Hyo; Oh, Jisu; Gyu Hwang, Seong; Won Kwon, Sung; Oh, Doyeun; Keun Kim, Nam

    2015-01-01

    Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3'-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3'-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3'-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention. PMID:26046315

  5. Effect of GDNF on depressive-like behavior, spatial learning and key genes of the brain dopamine system in genetically predisposed to behavioral disorders mouse strains.

    PubMed

    Naumenko, Vladimir S; Kondaurova, Elena M; Bazovkina, Daria V; Tsybko, Anton S; Ilchibaeva, Tatyana V; Khotskin, Nikita V; Semenova, Alina A; Popova, Nina K

    2014-11-01

    The effect of glial cell line-derived neurotrophic factor (GDNF) on behavior and brain dopamine system in predisposed to depressive-like behavior ASC (Antidepressant Sensitive Cataleptics) mice in comparison with the parental "nondepressive" CBA mice was studied. In 7days after administration (800ng, i.c.v.) GDNF decreased escape latency time and the path traveled to reach hidden platform in Morris water maze in ASC mice. GDNF enhanced depressive-like behavioral traits in both "nondepressive" CBA and "depressive" ASC mice. In CBA mice, GDNF decreased functional response to agonists of D1 (chloro-APB hydrobromide) and D2 (sumanirole maleate) receptors in tail suspension test, reduced D2 receptor gene expression in the substantia nigra and increased monoamine oxydase A (MAO A) gene expression in the striatum. GDNF increased D1 and D2 receptor genes expression in the nucleus accumbens of ASC mice but failed to alter expression of catechol-O-methyltransferase, dopamine transporter, MAO B and tyrosine hydroxylase genes in both investigated mouse strains. Thus, GDNF produced long-term genotype-dependent effect on behavior and the brain dopamine system. GDNF pretreatment (1) reduced D1 and D2 receptors functional responses and D2 receptor gene expression in s. nigra of CBA mice; (2) increased D1 and D2 receptor genes expression in n. accumbens of ASC mice and (3) improved spatial learning in ASC mice. GDNF enhanced depressive-like behavior both in CBA and ASC mice. The data suggest that genetically defined variance in the cross-talk between GDNF and brain dopamine system contributes to the variability of GDNF-induced responses and might be responsible for controversial GDNF effects. PMID:25101543

  6. DNA repair gene deficiency does not predispose human bronchial epithelial cells to benzo(a)pyrene-induced cell transformation.

    PubMed

    Xing, Xiumei; Liu, Caixia; Tang, Shifu; Li, Daochuan; Chen, Liping; Pang, Yaqin; Wang, Qing; Zhang, Bo; Zeng, Xiaowen; Chen, Wen; Xiao, Yongmei

    2012-06-01

    The development of cost and time-efficient in vitro assays to predict carcinogenicity of chemicals has become a very important direction for toxicological research. In this study, we generated a series of human bronchial epithelial (HBE) cells defect in DNA repair gene excision repair cross-completion 1 (ERCC1), excision repair cross-completion 2 (ERCC2), ataxia-telangiectasia mutated (ATM) and mutS homolog 2 (MSH2), respectively. The inhibition of gene expression was verified by detection of mRNA and protein levels of respective genes. The suppression of these DNA repair genes has no impact on cell proliferation or cell transformation. Although we found that the transgenic HBE cells were more sensitive in benzo(a)pyrene (BaP)-induced DNA damages measured by cytokinesis-block micronucleus (CBMN) assay and comet assay, we failed to observe enhanced effects on induction of cell transformation. HBE cells defect in DNA repair pathways did not exhibit malignantly transformed phenotype up to 20 weeks of BaP treatment, indicating that the deficiency of ERCC1, ERCC2, ATM, or MSH2 alone did not shorten the latency of cell transformation. In contrast, we found that HBE cells expressing H-Ras or c-Myc were transformed 8 or 12 weeks after BaP treatment. These findings demonstrate that silencing of a single DNA repair gene does not confer cells susceptible to chemical-induced cell transformation. PMID:22382310

  7. An Obesity-Predisposing Variant of the FTO Gene Regulates D2R-Dependent Reward Learning.

    PubMed

    Sevgi, Meltem; Rigoux, Lionel; Kühn, Anne B; Mauer, Jan; Schilbach, Leonhard; Hess, Martin E; Gruendler, Theo O J; Ullsperger, Markus; Stephan, Klaas Enno; Brüning, Jens C; Tittgemeyer, Marc

    2015-09-01

    Variations in the fat mass and obesity-associated (FTO) gene are linked to obesity. However, the underlying neurobiological mechanisms by which these genetic variants influence obesity, behavior, and brain are unknown. Given that Fto regulates D2/3R signaling in mice, we tested in humans whether variants in FTO would interact with a variant in the ANKK1 gene, which alters D2R signaling and is also associated with obesity. In a behavioral and fMRI study, we demonstrate that gene variants of FTO affect dopamine (D2)-dependent midbrain brain responses to reward learning and behavioral responses associated with learning from negative outcome in humans. Furthermore, dynamic causal modeling confirmed that FTO variants modulate the connectivity in a basic reward circuit of meso-striato-prefrontal regions, suggesting a mechanism by which genetic predisposition alters reward processing not only in obesity, but also in other disorders with altered D2R-dependent impulse control, such as addiction. Significance statement: Variations in the fat mass and obesity-associated (FTO) gene are associated with obesity. Here we demonstrate that variants of FTO affect dopamine-dependent midbrain brain responses and learning from negative outcomes in humans during a reward learning task. Furthermore, FTO variants modulate the connectivity in a basic reward circuit of meso-striato-prefrontal regions, suggesting a mechanism by which genetic vulnerability in reward processing can increase predisposition to obesity. PMID:26354923

  8. The CT-Element of The C-Myc Gene Does Not Predispose to Chromosomal Breakpoints in Burkitt'S Lymphoma

    PubMed Central

    Weber, Achim; Gutierrez, Marina I.; Levens, David

    2006-01-01

    Background: Chromosomal translocations are causally related to the development of many tumors. In Burkitt's lymphoma, abnormalities involving the c-myc gene are essential. The CT-element of the c-myc promoter adopts non-B-conformation in vivo and in vitro, and therefore provides a potential fragile site. Methods: We have developed a LM-PCR-based approach to test if chromosomal breakpoints indeed cluster in this region. Results: Amplifying both, wild-type as well as the translocated c-myc gene by LM-PCR, it was shown that chromosomal breakpoints did not cluster within the CT-element. Conclusions: Therefore, the CT-element is not especially susceptible to the formation of breakpoints leading to chromosomal translocations in Burkitt's lymphoma. PMID:16675879

  9. The Contribution of Whole Gene Deletions and Large Rearrangements to the Mutation Spectrum in Inherited Tumor Predisposing Syndromes.

    PubMed

    Smith, Miriam J; Urquhart, Jill E; Harkness, Elaine F; Miles, Emma K; Bowers, Naomi L; Byers, Helen J; Bulman, Michael; Gokhale, Carolyn; Wallace, Andrew J; Newman, William G; Evans, D Gareth

    2016-03-01

    Heterozygous whole gene deletions (WGDs), and intragenic microdeletions, account for a significant proportion of mutations underlying cancer predisposition syndromes. We analyzed the frequency and genotype-phenotype correlations of microdeletions in 12 genes (BRCA1, BRCA2, TP53, MSH2, MLH1, MSH6, PMS2, NF1, NF2, APC, PTCH1, and VHL) representing seven tumor predisposition syndromes in 5,897 individuals (2,611 families) from our center. Overall, microdeletions accounted for 14% of identified mutations. As expected, smaller deletions or duplications were more common (12%) than WGDs (2.2%). Where a WGD was identified in the germline in NF2, the mechanism of somatic second hit was not deletion, as previously described for NF1. For neurofibromatosis type 1 and 2, we compared the mechanism of germline deletion. Unlike NF1, where three specific deletion sizes account for most germline WGDs, NF2 deletion breakpoints were different across seven samples tested. One of these deletions was 3.93 Mb and conferred a severe phenotype, thus refining the region for a potential NF2 modifier gene to a 2.04-Mb region on chromosome 22. The milder phenotype of NF2 WGDs may be due to the apparent absence of chromosome 22 loss as the second hit. These observations of WGD phenotypes will be helpful for interpreting incidental findings from microarray analysis and next-generation sequencing. PMID:26615784

  10. Identification of Fetal and Maternal Single Nucleotide Polymorphisms in Candidate Genes That Predispose to Spontaneous Preterm Labor with Intact Membranes

    PubMed Central

    Romero, Roberto; Velez, Digna R.; Kusanovic, Juan Pedro; Hassan, Sonia S.; Mazaki-Tovi, Shali; Vaisbuch, Edi; Kim, Chong Jai; Chaiworapongsa, Tinnakorn; Pearce, Brad; Friel, Lara A.; Bartlett, Jacquelaine; Anant, Madan Kumar; Salisbury, Benjamin A.; Vovis, Gerald F.; Lee, Min Seob; Gomez, Ricardo; Behnke, Ernesto; Oyarzun, Enrique; Tromp, Gerard; Williams, Scott M.; Menon, Ramkumar

    2013-01-01

    Objective To determine whether maternal/fetal SNPs in candidate genes are associated with spontaneous preterm labor/delivery. Study Design A genetic association study was conducted in 223 mothers and 179 fetuses [preterm labor with intact membranes who delivered <37 weeks (PTB)], and 599 mothers and 628 fetuses (normal pregnancy): 190 candidate genes and 775 SNPs were studied. Single locus/haplotype association analyses were performed; FDR was used to correct for multiple testing (q*=0.15)]. Results 1) The strongest single locus associations with PTB were IL6R (fetus: p=0.000148) and TIMP2 (mother: p=0.000197), remaining significant after correction for multiple comparisons; 2) Global haplotype analysis indicated an association between a fetal DNA variant in IGF2 and maternal COL4A3 (global p=0.004 and 0.007, respectively). Conclusion A SNP involved in controlling fetal inflammation (IL6R) and DNA variants in maternal genes encoding for proteins involved in extracellular matrix biology approximately doubled the risk of PTB. PMID:20452482

  11. A genetic association study of maternal and fetal candidate genes that predispose to preterm prelabor rupture of membranes (PROM)

    PubMed Central

    ROMERO, Roberto; FRIEL, Lara A.; EDWARDS, Digna R. VELEZ; KUSANOVIC, Juan Pedro; HASSAN, Sonia S.; MAZAKI-TOVI, Shali; VAISBUCH, Edi; KIM, Chong Jai; EREZ, Offer; CHAIWORAPONGSA, Tinnakorn; PEARCE, Brad D.; BARTLETT, Jacquelaine; SALISBURY, Benjamin A.; ANANT, Madan Kumar; VOVIS, Gerald F.; LEE, Min Seob; GOMEZ, Ricardo; BEHNKE, Ernesto; OYARZUN, Enrique; TROMP, Gerard; WILLIAMS, Scott M.; MENON, Ramkumar

    2010-01-01

    Objective To determine whether maternal/fetal SNPs in candidate genes are associated with preterm prelabor rupture of membranes (pPROM). Study Design A case-control study was conducted in patients with pPROM (225 mothers and 155 fetuses) and 599 mothers and 628 fetuses with a normal pregnancy; 190 candidate genes and 775 SNPs were studied. Single locus/haplotype association analyses were performed; FDR was used to correct for multiple testing (q*=0.15)]. Results 1) A SNP in TIMP2 in mothers was significantly associated with pPROM(OR=2.12 95% CI [1.47-3.07], p = 0.000068), and this association remained significant after correction for multiple comparisons; 2) Haplotypes for COL4A3 in the mother were associated with pPROM (global p = 0.003); 3) Multilocus analysis identified a three locus model, which included maternal SNPs in COL1A2, DEFA5, and EDN1. Conclusion DNA variants in a maternal gene involved in extracellular matrix metabolism doubled the risk of pPROM. PMID:20673868

  12. Association of the MTHFR A1298C Variant with Unexplained Severe Male Infertility

    PubMed Central

    Eloualid, Abdelmajid; Abidi, Omar; Charif, Majida; El houate, Brahim; Benrahma, Houda; Louanjli, Noureddine; Chadli, Elbakkay; Ajjemami, Maria; Barakat, Abdelhamid; Bashamboo, Anu; McElreavey, Ken; Rhaissi, Houria; Rouba, Hassan

    2012-01-01

    The methylenetetrahydrofolate reductase (MTHFR) gene is one of the main regulatory enzymes involved in folate metabolism, DNA synthesis and remethylation reactions. The influence of MTHFR variants on male infertility is not completely understood. The objective of this study was to analyze the distribution of the MTHFR C677T and A1298C variants using PCR-Restriction Fragment Length Polymorphism (RFLP) in a case group consisting of 344 men with unexplained reduced sperm counts compared to 617 ancestry-matched fertile or normozoospermic controls. The Chi square test was used to analyze the genotype distributions of MTHFR polymorphisms. Our data indicated a lack of association of the C677T variant with infertility. However, the homozygous (C/C) A1298C polymorphism of the MTHFR gene was present at a statistically high significance in severe oligozoospermia group compared with controls (OR?=?3.372, 95% confidence interval CI?=?1.27–8.238; p?=?0.01431). The genotype distribution of the A1298C variants showed significant deviation from the expected Hardy-Weinberg equilibrium, suggesting that purifying selection may be acting on the 1298CC genotype. Further studies are necessary to determine the influence of the environment, especially the consumption of diet folate on sperm counts of men with different MTHFR variants. PMID:22457816

  13. Association of the MTHFR A1298C variant with unexplained severe male infertility.

    PubMed

    Eloualid, Abdelmajid; Abidi, Omar; Charif, Majida; El Houate, Brahim; Benrahma, Houda; Louanjli, Noureddine; Chadli, Elbakkay; Ajjemami, Maria; Barakat, Abdelhamid; Bashamboo, Anu; McElreavey, Ken; Rhaissi, Houria; Rouba, Hassan

    2012-01-01

    The methylenetetrahydrofolate reductase (MTHFR) gene is one of the main regulatory enzymes involved in folate metabolism, DNA synthesis and remethylation reactions. The influence of MTHFR variants on male infertility is not completely understood. The objective of this study was to analyze the distribution of the MTHFR C677T and A1298C variants using PCR-Restriction Fragment Length Polymorphism (RFLP) in a case group consisting of 344 men with unexplained reduced sperm counts compared to 617 ancestry-matched fertile or normozoospermic controls. The Chi square test was used to analyze the genotype distributions of MTHFR polymorphisms. Our data indicated a lack of association of the C677T variant with infertility. However, the homozygous (C/C) A1298C polymorphism of the MTHFR gene was present at a statistically high significance in severe oligozoospermia group compared with controls (OR?=?3.372, 95% confidence interval CI?=?1.27-8.238; p?=?0.01431). The genotype distribution of the A1298C variants showed significant deviation from the expected Hardy-Weinberg equilibrium, suggesting that purifying selection may be acting on the 1298CC genotype. Further studies are necessary to determine the influence of the environment, especially the consumption of diet folate on sperm counts of men with different MTHFR variants. PMID:22457816

  14. Association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and age of onset in schizophrenia.

    PubMed

    Vares, Maria; Saetre, Peter; Deng, Hong; Cai, Guiqing; Liu, Xiehe; Hansen, Thomas; Rasmussen, Henrik B; Werge, Thomas; Melle, Ingrid; Djurovic, Srdjan; Andreassen, Ole A; Agartz, Ingrid; Hall, Håkan; Terenius, Lars; Jönsson, Erik G

    2010-03-01

    Different lines of evidence indicate that methylenetetrahydrofolate reductase (MTHFR) functional gene polymorphisms, causative in aberrant folate-homocysteine metabolism, are associated with increased vulnerability to several heritable developmental disorders. Opposing views are expressed considering the possible association between MTHFR and susceptibility for schizophrenia. In order to evaluate if age of onset could explain some of this discrepancy we investigated the relationship between two functional MTHFR gene polymorphisms and age at onset in this disorder. Scandinavian patients (n = 820) diagnosed with schizophrenia, schizoaffective disorder, and schizophreniform disorder were investigated. Two functional MTHFR single nucleotide polymorphisms (SNPs; rs1801131 and rs1801133) were genotyped and the effect of MTHFR polymorphisms on the age of onset was examined with survival analysis. In an attempt to replicate the findings from the Scandinavian sample, the association between rs1801133 and age at onset was also analyzed in Chinese high-risk families, with two or more affected siblings (n = 243). Among the Scandinavian patients the functional MTHFR SNP rs1801133 (C677T) significantly affected age at onset of schizophrenia in a dose-dependent manner (P = 0.0015), with lower age of onset with increasing numbers of the mutant T-allele. There was no evidence of rs1801131 (A1298C) affecting age of onset in schizophrenia. Within the Chinese high-risk families carriers of the MTHFR 677T allele showed earlier age at onset than siblings being homozygous for the wild-type allele (P = 0.008). The MTHFR C677T polymorphism may play a role as a modifying factor for age of onset in schizophrenia. PMID:19746410

  15. ApcMin, A Mutation in the Murine Apc Gene, Predisposes to Mammary Carcinomas and Focal Alveolar Hyperplasias

    NASA Astrophysics Data System (ADS)

    Moser, Amy Rapaich; Mattes, Ellen M.; Dove, William F.; Lindstrom, Mary J.; Haag, Jill D.; Gould, Michael N.

    1993-10-01

    ApcMin (Min, multiple intestinal neoplasia) is a point mutation in the murine homolog of the APC gene. Min/+ mice develop multiple intestinal adenomas, as do humans carrying germ-line mutations in APC. Female mice carrying Min are also prone to develop mammary tumors. Min/+ mammary glands are more sensitive to chemical carcinogenesis than are +/+ mammary glands. Transplantation of mammary cells from Min/+ or +/+ donors into +/+ hosts demonstrates that the propensity to develop mammary tumors is intrinsic to the Min/+ mammary cells. Long-term grafts of Min/+ mammary glands also gave rise to focal alveolar hyperplasias, indicating that the presence of the Min mutation also has a role in the development of these lesions.

  16. The RETN gene rs1862513 polymorphism as a novel predisposing marker for familial Acne vulgaris in a Pakistani population

    PubMed Central

    Hussain, Sabir; Faraz, Ahmad; Iqbal, Tahir

    2015-01-01

    Resistin (RETN), recently found to be relevant to inflammation and inflammatory disorders. We, therefore, aimed to investigate the potential role of RETN gene polymorphism in pathogenesis of acne vulgaris with familial history. We investigated the RETN-420C/G polymorphism in 180 patients with acne vulgaris and 180 healthy individuals in a case-control association analysis. In this study, we also investigated the heritability of the RETN susceptible allele from 140 trio families with acne affected offspring. The genotyping was performed by polymerase chain reaction and direct DNA sequencing. The RETN-420C/G polymorphism was significantly associated with acne in patients compared with healthy controls (P=0.014). The minor allele G at -420 was more prevalent in cases vs. controls (P=0.002). The RETN-420C/G polymorphism was significantly associated with severity of acne vulgaris in patients (P=0.0097). The results of a transmission disequilibrium test revealed a significant association between the RETN-420C/G polymorphism and acne vulgaris (P<0.001). For the first time in the literature, to our knowledge, we demonstrate a significant association of the RETN-420C/G functional polymorphism with familial acne vulgaris. PMID:26124941

  17. Associations of MTHFR Gene Polymorphisms with Hypertension and Hypertension in Pregnancy: A Meta-Analysis from 114 Studies with 15411 Cases and 21970 Controls

    PubMed Central

    Yang, Boyi; Fan, Shujun; Zhi, Xueyuan; Li, Yongfang; Liu, Yuyan; Wang, Da; He, Miao; Hou, Yongyong; Zheng, Quanmei; Sun, Guifan

    2014-01-01

    Background Several epidemiological studies have investigated the associations of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms with hypertension (H) or hypertension in pregnancy (HIP). However, the results were controversial. We therefore performed a comprehensive meta-analysis to provide empirical evidences on the associations. Methodologies The English and Chinese databases were systematically searched to identify relevant studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the associations. Meta-regression, subgroup analysis, sensitivity analysis, cumulative meta-analysis and assessment of publication bias were performed in our study. Principal Findings A total of 114 studies with 15411 cases and 21970 controls were included, 111 studies with 15094 cases and 21633 controls for the C677T polymorphism and 21 with 2533 cases and 2976 controls for the A1298C polymorphism. Overall, the C677T polymorphism was significantly associated with H and HIP (H & HIP: OR = 1.26, 95% CI = 1.17–1.34; H: OR = 1.36, 95% CI = 1.20–1.53; HIP: OR = 1.21, 95% CI = 1.08–1.32). Stratified analysis by ethnicity revealed a significant association among East Asians and Caucasians, but not among Latinos, Black Africans, and Indians and Sri Lankans. In the stratified analyses according to source of controls, genotyping method, sample size and study quality, significant associations were observed in all the subgroups, with the exception of population based subgroup in H studies and large sample size and “others” genotyping method subgroups in HIP studies. For the A1298C polymorphism, no significant association was observed either in overall or subgroup analysis under all genetic models. Conclusions This meta-analysis suggests that the MTHFR C677T rather than A1298C polymorphism may be associated with H & HIP, especially among East Asians and Caucasians. PMID:24505291

  18. Genetic Variation in Renal Expression of Folate Receptor 1 (Folr1) Gene Predisposes Spontaneously Hypertensive Rats to Metabolic Syndrome.

    PubMed

    Pravenec, Michal; Kožich, Viktor; Krijt, Jakub; Sokolová, Jitka; Zídek, Václav; Landa, Vladimír; Mlejnek, Petr; Šilhavý, Jan; Šimáková, Miroslava; Škop, Vojt?ch; Trnovská, Jaroslava; Kazdová, Ludmila; Kajiya, Takashi; Wang, Jiaming; Kurtz, Theodore W

    2016-02-01

    Metabolism of homocysteine and other sulfur amino acids is closely associated with metabolism of folates. In this study, we analyzed the possible role of folates and sulfur amino acids in the development of features of the metabolic syndrome in the BXH/HXB recombinant inbred strains derived from the spontaneously hypertensive rat (SHR) and Brown Norway progenitors. We mapped a quantitative trait locus for cysteine concentrations to a region of chromosome 1 that contains a cis-acting expression quantitative trait locus regulating mRNA levels of folate receptor 1 (Folr1) in the kidney. Sequence analysis revealed a deletion variant in the Folr1 promoter region of the SHR. Transfection studies demonstrated that the SHR-promoter region of Folr1 is less effective in driving luciferase reporter gene expression than the Brown Norway promoter region of Folr1. Results in the SHR.BN-chr.1 congenic strain confirmed that the SHR variant in Folr1 cosegregates with markedly reduced renal expression of Folr1 and renal folate reabsorption, decreased serum levels of folate, increased serum levels of cysteine and homocysteine, increased adiposity, ectopic fat accumulation in liver and muscle, reduced muscle insulin sensitivity, and increased blood pressure. Transgenic rescue experiments performed by expressing a Folr1 transgene in the SHR ameliorated most of the metabolic disturbances. These findings are consistent with the hypothesis that inherited variation in the expression of Folr1 in the kidney influences the development of the metabolic syndrome and constitutes a previously unrecognized genetic mechanism that may contribute to increased risk for diabetes mellitus and cardiovascular disease. PMID:26667416

  19. Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

    PubMed Central

    Juárez-Velázquez, Rocio; Canto, Patricia; Canto-Cetina, Thelma; Rangel-Villalobos, Hector; Rosas-Vargas, Haydee; Rodríguez, Maricela; Canizales-Quinteros, Samuel; Velázquez Wong, Ana Claudia; Ordoñez-Razo, Rosa María; Vilchis-Dorantes, Guadalupe; Coral-Vázquez, Ramón Mauricio

    2010-01-01

    Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1) polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using χ2 tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups. PMID:20592457

  20. Genetic variations in MTHFR and gastric cardia adenocarcinoma susceptibility in the Chinese Han population

    PubMed Central

    Wang, Yafeng; Chen, Shuchen; Kang, Mingqiang; Tang, Weifeng; Gu, Haiyong; Yin, Jun; Huang, Ziyang

    2015-01-01

    Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms are associated with many types of cancers. The purpose of our study was to evaluate the effect of MTHFR single nucleotide polymorphisms (SNPs) on gastric cardia adenocarcinoma (GCA). We conducted a hospital-based case-control study. Three hundred and thirty cases with GCA and 608 controls were recruited. The ligation detection reaction (LDR) method was used to determine genotypes. The genotype MTHFR rs1801133 TT was significantly more frequent in cases than in controls (adjusted odds ratio (OR) = 1.46, 95% confidence interval (CI) = 1.04-2.05, P = 0.029) in a recessive model, after adjusting for age, sex and smoking and alcohol use. The haplotype MTHFR Grs4845882Ars4846048Trs1801133Crs9651118Ars3753584 was more frequent in cases than in controls (crude OR = 5.32, 95% CI = 2.34-12.10, P < 0.001). No association between other genotypes and haplotypes was observed. Our results suggest that the genotype MTHFR rs1801133 TT and the MTHFR Grs4845882Ars4846048Trs1801133Crs9651118Ars3753584 haplotype may be associated with susceptibility to GCA. Further studies are needed to confirm these findings. PMID:26770518

  1. Can Certain Genotypes Predispose to Poor Asthma Control in Children? A Pharmacogenetic Study of 9 Candidate Genes in Children with Difficult Asthma

    PubMed Central

    Almomani, Basima; Hawwa, Ahmed F.; Millership, Jeffrey S.; Heaney, Liam; Douglas, Isabella; McElnay, James C.; Shields, Michael D.

    2013-01-01

    Objective We tested the hypothesis that patients with difficult asthma have an increased frequency of certain genotypes that predispose them to asthma exacerbations and poor asthma control. Methods A total of 180 Caucasian children with confirmed asthma diagnosis were selected from two phenotypic groups; difficult (n?=?112) versus mild/moderate asthma (n?=?68) groups. All patients were screened for 19 polymorphisms in 9 candidate genes to evaluate their association with difficult asthma. Key Results The results indicated that LTA4H A-9188>G, TNF? G-308>A and IL-4R? A1727>G polymorphisms were significantly associated with the development of difficult asthma in paediatric patients (p<0.001, p?=?0.019 and p?=?0.037, respectively). Haplotype analysis also revealed two haplotypes (ATA haplotype of IL-4R? A1199>C, IL-4R? T1570>C and IL-4R? A1727>G and CA haplotype of TNF? C-863>A and TNF? G-308>A polymorphisms) which were significantly associated with difficult asthma in children (p?=?0.04 and p?=?0.018, respectively). Conclusions and Clinical Relevance The study revealed multiple SNPs and haplotypes in LTA4H, TNF? and IL4-R? genes which constitute risk factors for the development of difficult asthma in children. Of particular interest is the LTA4H A-9188>G polymorphism which has been reported, for the first time, to have strong association with severe asthma in children. Our results suggest that screening for patients with this genetic marker could help characterise the heterogeneity of responses to leukotriene-modifying medications and, hence, facilitate targeting these therapies to the subset of patients who are most likely to gain benefit. PMID:23573270

  2. Association of the MTHFR rs1801131 and rs1801133 variants in sporadic Parkinson's disease patients.

    PubMed

    Yuan, Lamei; Song, Zhi; Deng, Xiong; Xiong, Wei; Yang, Zhijian; Deng, Hao

    2016-03-11

    Parkinson's disease (PD) is a common age-dependent neurodegenerative movement disorder related to multiple factors, and genetic factors play an important role in the pathogenesis of PD. Variants in the methylenetetrahydrofolate reductase gene (MTHFR), a gene encoding a folate-dependent enzyme that is involved in homocysteine metabolism, have been reported to be associated with PD. To explore the role of the MTHFR gene in the development of PD in Chinese Han population, we analyzed two MTHFR variants (rs1801131 and rs1801133) in a patient cohort consisting of 512 patients with PD from mainland China and a control cohort consisting of 512 age, gender and ethnicity matched normal subjects. Statistically significant differences in genotypic and allelic frequencies were detected in the MTHFR variant rs1801133 (P=0.022 and 0.007, respectively; odds ratio=0.780, 95% confidence interval=0.651-0.934). In addition, the A-T haplotype of rs1801131-rs1801133 showed a protective role against PD development (P=0.007, odds ratio=0.779, 95% confidence interval=0.650-0.933). Our results suggested that the T allele of rs1801133 variant and A-T haplotype of rs1801131-rs1801133 in the MTHFR gene may decrease the risk of developing PD in Chinese Han population from mainland China. PMID:26806866

  3. MTHFR genetic polymorphism increases the risk of preterm delivery

    PubMed Central

    Nan, Yanrong; Li, Hongmei

    2015-01-01

    Aims: This study aimed to investigate the association between the methylene tetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms and premature delivery susceptibility. Methods: With matched age and gender, 108 premature delivery pregnant women as cases and 108 healthy pregnant women as controls were recruited in this case-control study. The cases and controls had same gestational weeks. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was adopted to analyze C677T and A1298C polymorphisms of the participants. Linkage disequilibrium (LD) and haplotype analysis were conducted by Haploview software. The differences for frequencies of gene type, allele and haplotypes in cases and controls were tested by chi-square test. The relevant risk of premature delivery was represented by odds ratios (ORs) with 95% confidence intervals (95% CIs). Results: TT gene type frequency of C677T polymorphsim was higher in cases than the controls (P=0.004, OR=3.077, 95% CI=1.469-6.447), so was allele T (P=0.002, OR=1.853, 95% CI=1.265-2.716). Whereas, CC gene type of A1298C polymorphism had a lower distribution in cases than the controls (P=0.008, OR=0.095, 95% CI=0.012-0.775), so was allele C (P=0.047, OR=0.610, 95% CI=0.384-0.970). Haplotype analysis and linkage disequilibrium test conducted on the alleles of two polymorphisms in MTHFR gene, we discovered that haplotype T-A had a higher distribution in cases, which indicated that susceptible haplotype T-A was the candidate factor for premature delivery. Conclusions: Gene type TT of MTHFR C677T polymorphism might make premature delivery risk rise while gene type CC of A1298C polymorphism might have protective influence on premature delivery. PMID:26261642

  4. Frequency of APOE, MTHFR and ACE polymorphisms in the Zambian population

    PubMed Central

    2014-01-01

    Background Polymorphisms within the apolipoprotein-E (APOE), Methylenetetrahydrofolate reductase (MTHFR) and Angiotensin I-converting enzyme (ACE) genes has been associated with cardiovascular and cerebrovascular disorders, Alzheimer’s disease and other complex diseases in various populations. The aim of the study was to analyze the allelic and genotypic frequencies of APOE, MTHFR C677T and ACE I/D gene polymorphisms in the Zambian population. Results The allele frequencies of APOE polymorphism in the Zambian populations were 13.8%, 59.5% and 26.7% for the ?2, ?3 and ?4 alleles respectively. MTHFR C677T and ACE I/D allele frequencies were 8.6% and 13.8% for the T and D minor alleles respectively. The ?2?2 genotype and TT genotype were absent in the Zambian population. The genetic distances between Zambian and other African and non-African major populations revealed an independent variability of these polymorphisms. Conclusion We found that the APOE ?3 allele and the I allele of the ACE were significantly high in our study population while there were low frequencies observed for the MTHFR 677 T and ACE D alleles. Our analysis of the APOE, MTHFR and ACE polymorphisms may provide valuable insight into the understanding of the disease risk in the Zambian population. PMID:24679048

  5. Two Mutations in the Caprine MTHFR 3'UTR Regulated by MicroRNAs Are Associated with Milk Production Traits

    PubMed Central

    Song, Yuxuan; Gao, Teyang; Lei, Yingnan; Cao, Binyun

    2015-01-01

    Background 5,10-Methylenetetrahydrofolate reductase (MTHFR) plays a central role in folate metabolism by irreversibly converting 5,10-methylenetetrahydrofolate to 5-methylenetetrahydrofolate, a predominant circulating form of folate. Folate is reportedly important for milk protein synthesis, and MTHFR may be a key regulatory point of folate metabolism for milk protein synthesis in mammary epithelial cells. Prior to this study, polymorphisms of the MTHFR gene were not associated with milk production traits from a breeding perspective. Single nucleotide polymorphisms (SNPs) at microRNA (miRNA) binding sites (miR-SNPs) can affect gene expression. This study aimed to identify the effects of miR-SNPs (g.2244A>G and g.2264A>G) in the caprine MTHFR 3' UTR on the milk production traits of dairy goats. Results Guanzhong dairy (GD, n = 325) goats were used to detect SNPs in the caprine MTHFR 3' UTR by DNA sequencing. Two novel SNPs (g.2244A>G and g.2264A>G) were identified in the said region. The homozygous haplotype A-G of the SNPs g.2244A>G and g.2264A>G was significantly associated with milk yield and milk protein levels in GD goats (P < 0.05). Functional assays indicated that the MTHFR 2244 A ? G substitution could increase the binding activity of hsa-miR-1266 with the MTHFR 3' UTR. The MTHFR 2264 A ? G substitution could decrease the binding activity of hsa-miR-616 with the MTHFR 3' UTR. In addition, we observed a significant increase in the MTHFR mRNA levels of homozygous haplotype A-G carriers relative to those of homozygous haplotype G-A carriers. These results indicated that both SNPs altered the MTHFR mRNA levels. These altered levels of MTHFR mRNA may account for the association of SNPs with milk production traits. Conclusions This study is the first to report that the g.2244A>G and g.2264A>G polymorphisms were associated with milk production traits in GD goats. Further investigations should explore the underlying miRNA-mediated mechanisms that are modified by the g.2244A>G and g.2264A>G SNPs. The current study evaluated these SNPs as potential genetic markers in goats, with potential applications in breeding programs. PMID:26186555

  6. High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice12345

    PubMed Central

    Christensen, Karen E; Mikael, Leonie G; Leung, Kit-Yi; Lévesque, Nancy; Deng, Liyuan; Wu, Qing; Malysheva, Olga V; Best, Ana; Caudill, Marie A; Greene, Nicholas DE

    2015-01-01

    Background: Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions. Objective: Our goal was to investigate the impact of high folic acid intake on liver disease and methyl metabolism. Design: Folic acid–supplemented diet (FASD, 10-fold higher than recommended) and control diet were fed to male Mthfr+/+ and Mthfr+/− mice for 6 mo to assess gene-nutrient interactions. Liver pathology, folate and choline metabolites, and gene expression in folate and lipid pathways were examined. Results: Liver and spleen weights were higher and hematologic profiles were altered in FASD-fed mice. Liver histology revealed unusually large, degenerating cells in FASD Mthfr+/− mice, consistent with nonalcoholic fatty liver disease. High folic acid inhibited MTHFR activity in vitro, and MTHFR protein was reduced in FASD-fed mice. 5-Methyltetrahydrofolate, SAM, and SAM/S-adenosylhomocysteine ratios were lower in FASD and Mthfr+/− livers. Choline metabolites, including phosphatidylcholine, were reduced due to genotype and/or diet in an attempt to restore methylation capacity through choline/betaine-dependent SAM synthesis. Expression changes in genes of one-carbon and lipid metabolism were particularly significant in FASD Mthfr+/− mice. The latter changes, which included higher nuclear sterol regulatory element-binding protein 1, higher Srepb2 messenger RNA (mRNA), lower farnesoid X receptor (Nr1h4) mRNA, and lower Cyp7a1 mRNA, would lead to greater lipogenesis and reduced cholesterol catabolism into bile. Conclusions: We suggest that high folic acid consumption reduces MTHFR protein and activity levels, creating a pseudo-MTHFR deficiency. This deficiency results in hepatocyte degeneration, suggesting a 2-hit mechanism whereby mutant hepatocytes cannot accommodate the lipid disturbances and altered membrane integrity arising from changes in phospholipid/lipid metabolism. These preliminary findings may have clinical implications for individuals consuming high-dose folic acid supplements, particularly those who are MTHFR deficient. PMID:25733650

  7. The clinical impact of MTHFR polymorphism on the vascular complications of sickle cell disease.

    PubMed

    Moreira Neto, F; Lourenço, D M; Noguti, M A E; Morelli, V M; Gil, I C P; Beltrão, A C S; Figueiredo, M S

    2006-10-01

    Sickle cell disease (SCD) is one of the most common inherited diseases in the world and the patients present notorious clinical heterogeneity. It is known that patients with SCD present activation of the blood coagulation and fibrinolytic systems, especially during vaso-occlusive crises, but also during the steady state of the disease. We determined if the presence of the factor V gene G1691A mutation (factor V Leiden), the prothrombin gene G20210A variant, and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism may be risk factors for vascular complications in individuals with SCD. We studied 53 patients with SCD (60% being women), 29 with SS (sickle cell anemia; 28 years, range: 13-52 years) and 24 with SC (sickle-hemoglobin C disease; 38.5 years, range: 17-72 years) hemoglobinopathy. Factor V Leiden, MTHFR C677T polymorphism, and prothrombin G20210A variant were identified by PCR followed by further digestion of the PCR product with specific endonucleases. The following vascular complications were recorded: stroke, retinopathy, acute thoracic syndrome, and X-ray-documented avascular necrosis. Only one patient was heterozygous for factor V Leiden (1.8%) and there was no prothrombin G20210A variant. MTHFR 677TT polymorphism was detected in 1 patient (1.8%) and the heterozygous form 677TC was observed in 18 patients (34%, 9 with SS and 9 with SC disease), a prevalence similar to that reported by others. No association was detected between the presence of the MTHFR 677T allele and other genetic modulation factors, such as alpha-thalassemia, beta-globin gene haplotype and fetal hemoglobin. The presence of the MTHFR 677T allele was associated with the occurrence of vascular complications in SCD, although this association was not significant when each complication was considered separately. In conclusion, MTHFR C677T polymorphism might be a risk factor for vascular complications in SCD. PMID:16906320

  8. Increased risk of the abdominal aortic aneurysm in carriers of the MTHFR 677T allele.

    PubMed

    Strauss, Ewa; Waliszewski, Krzysztof; Gabriel, Marcin; Zapalski, Stanis?aw; Pawlak, Andrzej L

    2003-01-01

    Abdominal aortic aneurysm (AAA) presents itself as a progressive dilation of the abdominal aorta, leading--if untreated--to rupture. It is a common disease of the elderly, with a complex etiology. Several genetic, biochemical and environmental factors are recognized as relevant for the pathogenesis of AAA. We determined the polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene within the fourth exon (C677T) in 63 patients with AAA and compared it to that in 75 subjects of the population sample. The frequencies of the C/C, C/T and T/T genotypes were 65%, 27%, and 8% in the population sample and 33%, 60%, and 6% in the patients. This corresponds to a 4.4-fold greater risk of AAA in subjects who have the 677C/T variant of MTHFR, as compared with those who are 677C/C (p < 0.0001; 95% CI=2.11-9.34). The frequency of allele MTHFR 677T in patients (0.37) was higher than in the population sample (0.21; p < 0.007). This association between the common allele of the MTHFR gene--MTHFR 677T--and the development of AAA suggests that elevated homocysteine (Hcy) may disturb the function of the aortic wall. The disturbance may involve enhancement of elastin degradation, the process enhanced by mild hyperhomocysteinemia in minipigs. The magnitude of this effect, which refers to the AAA patients unselected for familial occurrence, indicates that the disturbance of aortic wall physiology caused by the presence of the MTHFR 677T allele is greater than the effect of the earlier described allele disequilibrium at the polymorphic alleles of the PAI1 (plasminogen activator inhibitor 1) gene seen only in familial cases of AAA. PMID:12590185

  9. C677T and A1298C MTHFR polymorphisms, a challenge for antifolate and fluoropyrimidine-based therapy personalisation.

    PubMed

    De Mattia, Elena; Toffoli, Giuseppe

    2009-05-01

    Pharmacogenetics represents an exciting, new promising tool for the individualisation of therapy. Several genetic polymorphisms and haplotypes have been considered in an attempt to optimise therapy with specific drugs but, up to now, their clinical applications remain limited. 5,10-Methylenetetrahydrofolate reductase (MTHFR), a key enzyme of one-carbon metabolism, catalyses the irreversible conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. Two common non-synonymous variants, the C677T (Ala222Val) and A1298C (Glu429Ala), were described for the MTHFR gene and associated with a decreased enzymatic activity and an alteration of intracellular folate distribution. Other MTHFR polymorphisms with marginal impact on enzymatic activity were also reported. Several published clinical studies have investigated the potential predictive role of C677T and A1298C genetic variants on toxicity and efficacy of antifolate and fluoropyrimidine agents, such as methotrexate (MTX), 5-fluorouracil (5-FU) and raltitrexed. Many of these studies show significant associations with MTHFR variants, but others report neither association nor opposite results. A significant interaction between MTHFR polymorphisms and nutrient/environmental factors (i.e. folate status) as well as the ethnicity was reported. Finally, a haplotype approach and the combined analysis of multiple folate pathway gene variants seem to provide a more comprehensive strategy compared to single-locus investigations. The aim of this review is to critically analyse the available data on the importance of MTHFR polymorphisms in modulating the clinical outcome of antifolate and fluoropyrimidine therapies. PMID:19144510

  10. Myocardial infarction in a newborn heterozygous for the MTHFR C677T mutation.

    PubMed

    Clark, Amy B; Stokes, Theophil A; Krous, Henry F; Carbine, Douglas N

    2012-01-01

    Neonatal myocardial infarction secondary to congenital heart disease, anomalous coronary artery anatomy, thromboembolism, coagulopathy, birth asphyxia, and unknown causes has been previously reported. We now report an infant who suffered a massive myocardial infarction during birth, requiring extensive resuscitation and aggressive management. A thrombus, the origin of which was not detected on autopsy, was found occluding the proximal left coronary artery several hours after birth. Genetic studies revealed a single copy variant of the MTHFR C677T mutation that we speculate may have predisposed the infant to coronary thrombosis. PMID:22339112

  11. The association between first trimester micronutrient intake, MTHFR genotypes, and global DNA methylation in pregnant women

    PubMed Central

    La Merrill, Michele; Torres-Sánchez, Luisa; Ruiz-Ramos, Rubén; López-Carrillo, Lizbeth; Cebrián, Mariano E; Chen, Jia

    2012-01-01

    Objective Our aim was to evaluate possible associations between consumption of micronutrients involved in one-carbon metabolism, MTHFR genotypes, and global DNA methylation in pregnant women. Methods A semi-quantitative dietary questionnaire was administered to 195 women during their first trimester in Morelos, Mexico. Two functional polymorphisms of the key folate-metabolizing gene, i.e. MTHFR 677 C>T and 1298 A>C, as well as global DNA methylation were assessed in peripheral blood drawn during the interview. Results Independent of maternal age and caloric intake, vitamin B6 deficiency was associated with 1.8 fold increased risk of hypomethylation in women carrying the MTHFR 677 T allele. Conclusions There exists a subpopulation that is more susceptible to B vitamin deficiencies. PMID:21443409

  12. Maternal Supplementary Folate Intake, Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms and the Risk of Orofacial Cleft in Iranian Children

    PubMed Central

    Ebadifar, Asghar; KhorramKhorshid, Hamid Reza; Kamali, Koorosh; Salehi Zeinabadi, Mehdi; Khoshbakht, Tayyebeh; Ameli, Nazila

    2015-01-01

    Background: The purpose of this study was to describe the association of MTHFR gene single nucleotide polymorphisms (C677T and A1298C) and maternal supplementary folate intake with orofacial clefts in the Iranian population. Methods: In this case-control study, peripheral venous blood was taken from 65 patients with orofacial clefts and 215 unaffected controls for DNA extraction and kept in EDTA for further analysis. The genotyping was carried out using Polymerase Chain Reaction (PCR) followed by Restriction Fragment Length Polymorphism (RFLP) and gel electrophoresis. Data were analyzed using Chi square test and logistic regression tests. Results: Genotype frequencies of 677TT were reported to be 13.5 and 36.1% in controls and CL/P patients, respectively, which showed a significant difference compared to CC as reference (OR=4.118; 95% CI=1.997–8.492; p=0.001). Conversely, 1298CC with frequencies of 10.8 and 12.7% in controls and patients, respectively, showed no significant difference compared to AA (OR=2.359; 95% CI=0.792–7.023; p=0.123). Comparing patients whose mothers did not report the folate supplement intake during pregnancy, to controls, it was observed that lack of folate intake was a predisposing factor for having a child with oral clefts (OR=5/718, p=0.000). Conclusion: Children carrying the 677TT variant of the MTHFR gene may have an increased risk of CL/P. In addition, the finding that the risk associated with this allele was obviously higher when the mothers didn’t use folic acid, supports the hypothesis that folic acid may play a role in the etiology of CL/P. PMID:26140186

  13. Low-penetrance alleles predisposing to sporadic colorectal cancers: a French case-controlled genetic association study

    PubMed Central

    Küry, Sébastien; Buecher, Bruno; Robiou-du-Pont, Sébastien; Scoul, Catherine; Colman, Hélène; Le Neel, Tanguy; Le Houérou, Claire; Faroux, Roger; Ollivry, Jean; Lafraise, Bernard; Chupin, Louis-Dominique; Sébille, Véronique; Bézieau, Stéphane

    2008-01-01

    Background Sporadic colorectal cancers (CRC) are multifactorial diseases resulting from the combined effects of numerous genetic, environmental and behavioral risk factors. Genetic association studies have suggested low-penetrance alleles of extremely varied genes to be involved in susceptibility to CRC in Caucasian populations. Methods Through a large genetic association study based on 1023 patients with sporadic CRC and 1121 controls, we tested a panel of these low-penetrance alleles to find out whether they could determine "genotypic profiles" at risk for CRC among individuals of the French population. We examined 52 polymorphisms of 35 genes – drawn from inflammation, xenobiotic detoxification, one-carbon, insulin signaling, and DNA repair pathways – for their possible contribution to colorectal carcinogenesis. The risk of cancer associated with these polymorphisms was assessed by calculation of odds ratios (OR) using multivariate analyses and logistic regression. Results Whereas all these polymorphisms had previously been found to be associated with CRC risk, especially in Caucasian populations, we were able to replicate the association for only five of them. Three SNPs were shown to increase CRC risk: PTGS1 c.639C>A (p.Gly213Gly), IL8 c.-352T>A, and MTHFR c.1286A>C (p.Ala429Glu). On the contrary, two other SNPs, PLA2G2A c.435+230C>T and PPARG c.1431C>T (p.His477His), were associated with a decrease in CRC risk. Further analyses highlighted genotypic combinations having a greater predisposing effect on CRC (OR 1.97, 95%CI 1.31–2.97, p = 0.0009) than the allelic variants that were examined separately. Conclusion The identification of CRC-predisposing combinations, composed of alleles PTGS1 c.639A, PLA2G2A c.435+230C, PPARG c.1431C, IL8 c.-352A, and MTHFR c.1286C, highlights the importance of inflammatory processes in susceptibility to sporadic CRC, as well as a possible crosstalk between inflammation and one-carbon pathways. PMID:18992148

  14. Evaluation of High Resolution Melting for MTHFR C677T Genotyping in Congenital Heart Disease

    PubMed Central

    Yue, Shuying; Zhang, Kun; Wang, Hui; Dong, Rui; Yang, Xiaomeng; Liu, Yi; Ma, Yanhui

    2016-01-01

    Background High resolution melting (HRM) is a simple, flexible and low-cost mutation screening technique. The methylenetetrahydrofolate reductase (MTHFR) gene encoding a critical enzyme, potentially affects susceptibility to some congenital defects like congenital heart disease (CHD). We evaluate the performance of HRM for genotyping of the MTHFR gene C677T locus in CHD cases and healthy controls of Chinese Han population. Methods A total of 315 blood samples from 147 CHD patients (male72, female 75) and 168 healthy controls (male 92, female 76) were enrolled in the study. HRM was utilized to genotype MTHFR C677T locus of all the samples. The results were compared to that of PCR-RFLP and Sanger sequencing. The association of the MTHFR C677T genotypes and the risk of CHD was analyzed using odds ratio with their 95% confidence interval (CIs) from unconditional logistic regression. Results All the samples were successfully genotyped by HRM within 1 hour and 30 minutes while at least 6 hours were needed for PCR-RFLP and sequencing. The genotypes of MTHFR C677T CC, CT, and TT were 9.52%, 49.66%, and 40.82% in CHD group but 29.17%, 50% and 20.83% in control group, which were identical using both methods of HRM and PCR-RFLP, demonstrating the sensitivity and specificity of HRM were all 100%. Conclusion MTHFR C677T is a potential risk factor for CHD in our local residents of Shandong province in China. HRM is a fast, sensitive, specific and reliable method for clinical application of genotyping. PMID:26990189

  15. Gender-specific effect of Mthfr genotype and neonatal vigabatrin interaction on synaptic proteins in mouse cortex.

    PubMed

    Blumkin, Elinor; Levav-Rabkin, Tamar; Melamed, Osnat; Galron, Dalia; Golan, Hava M

    2011-07-01

    The enzyme methylenetetrahydrofolate reductase (MTHFR) is a part of the homocysteine and folate metabolic pathways, affecting the methylations of DNA, RNA, and proteins. Mthfr deficiency was reported as a risk factor for neurodevelopmental disorders such as autism spectrum disorder and schizophrenia. Neonatal disruption of the GABAergic system is also associated with behavioral outcomes. The interaction between the epigenetic influence of Mthfr deficiency and neonatal exposure to the GABA potentiating drug vigabatrin (GVG) in mice has been shown to have gender-dependent effects on mice anxiety and to have memory impairment effects in a gender-independent manner. Here we show that Mthfr deficiency interacts with neonatal GABA potentiation to alter social behavior in female, but not male, mice. This impairment was associated with a gender-dependent enhancement of proteins implicated in excitatory synapse plasticity in the female cortex. Reelin and fragile X mental retardation 1 protein (FMRP) levels and membrane GluR1/GluR2 ratios were elevated in wild-type mice treated neonatally with GVG and in Mthfr+/- mice treated with saline, but not in Mthfr+/- mice treated with GVG, compared with control groups (wild type treated with saline). A minor influence on the levels of these proteins was observed in male mice cortices, possibly due to high basal protein levels. Interaction between gender, genotype, and treatment was also observed in the GABA pathway. In female mice, GABA Aα2/gephyrin ratios were suppressed in all test groups; in male mice, a genotype-specific enhancement of GABA Aα2/gephyrin was observed. The lack of an effect on either reln or Fmr1 transcription suggests post-transcriptional regulation of these genes. Taken together, these findings suggest that Mthfr deficiency may interact with neonatal GABA potentiation in a gender-dependent manner to interrupt synaptic function. This may illustrate a possible mechanism for the epigenetic involvement of Mthfr deficiency in neurodevelopmental disorders. PMID:21490592

  16. Maternal MTHFR genotype and haplotype predict deficits in early cognitive development in a lead-exposed birth cohort in Mexico City1234

    PubMed Central

    Hu, Howard; Wright, Robert O; Kordas, Katarzyna; Ettinger, Adrienne S; Sánchez, Brisa N; Cantonwine, David; Lazarus, Alicia L; Cantoral, Alejandra; Schnaas, Lourdes; Téllez-Rojo, Martha Maria; Hernández-Avila, Mauricio

    2010-01-01

    Background: Maternal folate nutritional status and prenatal lead exposure can influence fetal development and subsequent health. The methylenetetrahydrofolate reductase (MTHFR) gene is important for folate metabolism, and 2 common polymorphisms, C677T and A1298C, reduce enzymatic activity; C677T is present at high penetrance in Mexican populations. Objective: The objective of this study was to examine potential links between maternal and child MTHFR polymorphisms and child neurodevelopment in a lead-exposed population. Design: Data regarding MTHFR polymorphisms C677T and A1298C, peri- and postnatal lead measures, and Bayley Mental Development Index at 24 mo of age (MDI-24) scores were available for 255 mother-child pairs who participated in the ELEMENT (Early Life Exposures in Mexico to Environmental Toxicants) study during 1994–1995. Results: In covariate-adjusted regression models, maternal MTHFR 677 genotype predicted MDI-24 scores, in which each copy of the maternal MTHFR 677T variant allele was associated with lower MDI-24 scores (? = ?3.52; 95% CI: ?6.12, ?0.93; P = 0.004). Maternal MTHFR haplotype also predicted MDI-24 scores (mean ± SE: 93.3 ± 1.2 for 677C-1298A compared with 89.9 ± 0.8 for 677T-1298A; P < 0.05). MDI-24 scores were not associated with maternal MTHFR 1298 genotype or child MTHFR genotypes. We did not observe significant MTHFR genotype × lead interactions with respect to any of the subject biomarkers of lead exposure. Conclusions: The maternal MTHFR 677T allele is an independent predictor of poorer child neurodevelopment at 24 mo. These results suggest that maternal genetic variations in folate metabolism during pregnancy may program offspring neurodevelopment trajectories. Further research is warranted to determine the generalizability of these results across other populations. PMID:20504979

  17. Association Between MTHFR Genetic Variants and Multiple Sclerosis in a Southern Iranian Population.

    PubMed

    Naghibalhossaini, Fakhraddin; Ehyakonandeh, Hesam; Nikseresht, Alireza; Kamali, Eskandar

    2015-01-01

    Multiple sclerosis (MS) is a demyelinating neuro- inflammatory autoimmune disease of the central nervous system. Genetic predisposition has long been suspected in the etiology of this disease. The association between MTHFR polymorphisms and MS has been ivestigated in different ethnic groups. We investigated the association between MTHFR C677T and A1298C missense variants and MS in 180 patients and 231 age- and gender-matched healthy controls in a Southern Iranian population. The mutagenically separated PCR (MS-PCR) and PCR-RFLP methods were used to genotype MTHFR at position 677 and 1298, respectively. Compared with controls, we observed a strong association between two MTHFR variants and the risk of developing MS. Subjects carrying 677T allele (CT and TT genotypes) had increased susceptibility to MS as compared to those carrying CC genotype (odds ratio (OR) for CT= 2.9, 95% confidence interval (95% CI)= 1.88-4.49; OR for TT= 6.23, 95% CI= 3.08-12.59). The variant 1298AC genotype also increased the risk for MS among our study population (OR= 2.14, 95% CI= 1.37-3.34). Combined genotype analysis for two MTHFR SNPs revealed that compared to the wild type genotypes (677CC/1298AA), 3 genotypes including TT/AC, CT/AC, and TT/AA were significantly at increased risk for MS development (OR= 13.9, 5.3, and 4.9, respectively). Our results suggest a possible gene dose- dependent association between MTHFR mutrant alleles and the risk of MS development. PMID:26261797

  18. Association Between MTHFR Genetic Variants and Multiple Sclerosis in a Southern Iranian Population

    PubMed Central

    Naghibalhossaini, Fakhraddin; Ehyakonandeh, Hesam; Nikseresht, Alireza; Kamali, Eskandar

    2015-01-01

    Multiple sclerosis (MS) is a demyelinating neuro- inflammatory autoimmune disease of the central nervous system. Genetic predisposition has long been suspected in the etiology of this disease. The association between MTHFR polymorphisms and MS has been ivestigated in different ethnic groups. We investigated the association between MTHFR C677T and A1298C missense variants and MS in 180 patients and 231 age- and gender-matched healthy controls in a Southern Iranian population. The mutagenically separated PCR (MS-PCR) and PCR-RFLP methods were used to genotype MTHFR at position 677 and 1298, respectively. Compared with controls, we observed a strong association between two MTHFR variants and the risk of developing MS. Subjects carrying 677T allele (CT and TT genotypes) had increased susceptibility to MS as compared to those carrying CC genotype (odds ratio (OR) for CT= 2.9, 95% confidence interval (95% CI)= 1.88-4.49; OR for TT= 6.23, 95% CI= 3.08-12.59). The variant 1298AC genotype also increased the risk for MS among our study population (OR= 2.14, 95% CI= 1.37-3.34). Combined genotype analysis for two MTHFR SNPs revealed that compared to the wild type genotypes (677CC/1298AA), 3 genotypes including TT/AC, CT/AC, and TT/AA were significantly at increased risk for MS development (OR= 13.9, 5.3, and 4.9, respectively). Our results suggest a possible gene dose- dependent association between MTHFR mutrant alleles and the risk of MS development. PMID:26261797

  19. A potential interaction between COMT and MTHFR genetic variants in Han Chinese patients with bipolar II disorder.

    PubMed

    Wang, Liang-Jen; Lee, Sheng-Yu; Chen, Shiou-Lan; Chang, Yun-Hsuan; Chen, Po See; Huang, San-Yuan; Tzeng, Nian-Sheng; Chen, Kao Chin; Lee, I Hui; Wang, Tzu-Yun; Yang, Yen Kuang; Lu, Ru-Band

    2015-01-01

    Bipolar II disorder (BP-II), characterized by recurrent dysregulation of mood, is a serious and chronic psychiatric illness. However, BP-II is commonly under-recognized, even in psychiatric settings. Because dopaminergic disturbance is thought to be involved in the development of bipolar disorder (BPD), it seems essential to investigate dopamine-related genes like the catechol-O-methyltransferase (COMT) gene, which are involved in dopamine metabolism, and the methylenetetrahydrofolate reductase (MTHFR) gene, which may affect COMT methylation and COMT function. The current study examined the association and interaction of the COMT Val158Met and MTHFR C677T variants with BP-II. Nine hundred seventy-eight participants were recruited: 531 with BP-II and 447 healthy controls. The genotypes of the COMT and MTHFR polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant interaction effect of the COMT Val158Met Val/Val genotype and the MTHFR C677T C/T + T/T genotype (P = 0.039) for the protective effect on the odds of developing BP-II. Our findings support preliminary evidence that the COMT and MTHFR genes interact in BP-II, and they imply the connection of both dopaminergic pathways and methylation pathways in the pathogenesis of BP-II. PMID:25744938

  20. A potential interaction between COMT and MTHFR genetic variants in Han Chinese patients with bipolar II disorder

    PubMed Central

    Wang, Liang-Jen; Lee, Sheng-Yu; Chen, Shiou-Lan; Chang, Yun-Hsuan; Chen, Po See; Huang, San-Yuan; Tzeng, Nian-Sheng; Chen, Kao Chin; Lee, I. Hui; Wang, Tzu-Yun; Yang, Yen Kuang; Lu, Ru-Band

    2015-01-01

    Bipolar II disorder (BP-II), characterized by recurrent dysregulation of mood, is a serious and chronic psychiatric illness. However, BP-II is commonly under-recognized, even in psychiatric settings. Because dopaminergic disturbance is thought to be involved in the development of bipolar disorder (BPD), it seems essential to investigate dopamine-related genes like the catechol-O-methyltransferase (COMT) gene, which are involved in dopamine metabolism, and the methylenetetrahydrofolate reductase (MTHFR) gene, which may affect COMT methylation and COMT function. The current study examined the association and interaction of the COMT Val158Met and MTHFR C677T variants with BP-II. Nine hundred seventy-eight participants were recruited: 531 with BP-II and 447 healthy controls. The genotypes of the COMT and MTHFR polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant interaction effect of the COMT Val158Met Val/Val genotype and the MTHFR C677T C/T + T/T genotype (P = 0.039) for the protective effect on the odds of developing BP-II. Our findings support preliminary evidence that the COMT and MTHFR genes interact in BP-II, and they imply the connection of both dopaminergic pathways and methylation pathways in the pathogenesis of BP-II. PMID:25744938

  1. Association between methylenetetrahydrofolate reductase (MTHFR) polymorphism and carotid intima medial thickness progression in post ischaemic stroke patient

    PubMed Central

    Faradz, Sultana M.H.; Sari, Stefani; Hadisaputro, Soeharyo

    2015-01-01

    Background Hyperhomocysteinemia is associated with an increased risk of atherosclerosis. The main cause of elevated levels of homocysteine is 677T allele, the gene encoded by methylenetetrahydrofolate reductase (MTHFR). Carotid atherosclerosis progression, which can be measured by examination of carotid intima-media thickness (C-IMT), is a predictor of recurrent ischemic stroke. The objective of this study was to determine a relationship between MTHFR polymorphism, homocysteine ??levels, and increased C-IMT in post- ischemic stroke patients. Methods This was an epidemiological prospective observational cohort study involving 71 patients with post-ischemic stroke subject of the first (onset 1 month) admitted in the Neurology Clinic of Kariadi Hospital during 2012 to 2013. C-IMT was examined using carotid duplex ultrasound at 1st, 6th, and 12th month after stroke onset. MTHFR gene polymorphism was examined using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP). Homocysteine level was measured using Axis® Homocysteine EIA. Results We found 3 categories of MTHFR gene variation, i.e., 677T/T, 677T/C, and 677C/C. The most frequent allele was MTHFR 677C (88.9%), while the MTHFR 677T allele frequency was 11.1%. The majority allele of the subject population was 677C/C, however, there were 3 subjects (4.2%) who had 677T/T allele. The 677T/T allele group had normal homocysteine level and the lowest mean C-IMT among others. Conclusions This study supports that the MTHFR 677T allele polymorphism is not associated with hyperhomocysteinemia as well as an increase in C-IMT in post ischemic stroke patients. PMID:26734634

  2. Candidate-gene analysis of white matter hyperintensities on neuroimaging

    PubMed Central

    Tran, Theresa; Cotlarciuc, Ioana; Yadav, Sunaina; Hasan, Nazeeha; Bentley, Paul; Levi, Christopher; Worrall, Bradford B; Meschia, James F; Rost, Natalia; Sharma, Pankaj

    2016-01-01

    Background White matter hyperintensities (WMH) are a common radiographic finding and may be a useful endophenotype for small vessel diseases. Given high heritability of WMH, we hypothesised that certain genotypes may predispose individuals to these lesions and consequently, to an increased risk of stroke, dementia and death. We performed a meta-analysis of studies investigating candidate genes and WMH to elucidate the genetic susceptibility to WMH and tested associated variants in a new independent WMH cohort. We assessed a causal relationship of WMH to methylene tetrahydrofolate reductase (MTHFR). Methods Database searches through March 2014 were undertaken and studies investigating candidate genes in WMH were assessed. Associated variants were tested in a new independent ischaemic cohort of 1202 WMH patients. Mendelian randomization was undertaken to assess a causal relationship between WMH and MTHFR. Results We identified 43 case-control studies interrogating eight polymorphisms in seven genes covering 6,314 WMH cases and 15,461 controls. Fixed-effects meta-analysis found that the C-allele containing genotypes of the aldosterone synthase CYP11B2 T(−344)C gene polymorphism were associated with a decreased risk of WMH (OR=0.61; 95% CI, 0.44 to 0.84; p=0.003). Using mendelian randomisation the association among MTHFR C677T, homocysteine levels and WMH, approached, but did not reach, significance (expected OR=1.75; 95% CI, 0.90−3.41; observed OR=1.68; 95% CI, 0.97−2.94). Neither CYP11B2 T(−344)C nor MTHFR C677T were significantly associated when tested in a new independent cohort of 1202 patients with WMH. Conclusions There is a genetic basis to WMH but anonymous genome wide and exome studies are more likely to provide novel loci of interest. PMID:25835038

  3. Association of genetic polymorphism of PPAR?-2, ACE, MTHFR, FABP-2 and FTO genes in risk prediction of type 2 diabetes mellitus.

    PubMed

    Abbas, Shania; Raza, Syed Tasleem; Ahmed, Faisal; Ahmad, Absar; Rizvi, Saliha; Mahdi, Farzana

    2013-01-01

    Type 2 diabetes mellitus (T2DM) is a non-autoimmune, complex, heterogeneous and polygenic metabolic disease condition characterized by persistent elevated blood glucose levels (hyperglycemia). India as said to be the diabetic capital of the world is likely to experience the largest increase in T2DM and a greater number of diabetic individuals in the world by the year 2030. Identification of specific genetic variations in a particular ethnic group has a critical role in understanding the risk of developing T2DM in a much efficient way in future. These genetic variations include numerous types of polymorphisms among which single nucleotide polymorphisms (SNPs) is the most frequent. SNPs are basically located within the regulatory elements of several gene sequences. There are scores of genes interacting with various environmental factors affecting various pathways and sometimes even the whole signalling network that cause diseases like T2DM. This review discusses the biomarkers for early risk prediction of T2DM. Such predictions could be used in order to understand the pathogenesis of T2DM and to better diagnostics, treatment, and eventually prevention. PMID:24156506

  4. Association of Genetic polymorphism of PPAR?-2, ACE, MTHFR, FABP-2 and FTO genes in risk prediction of type 2 diabetes mellitus

    PubMed Central

    2013-01-01

    Type 2 diabetes mellitus (T2DM) is a non-autoimmune, complex, heterogeneous and polygenic metabolic disease condition characterized by persistent elevated blood glucose levels (hyperglycemia). India as said to be the diabetic capital of the world is likely to experience the largest increase in T2DM and a greater number of diabetic individuals in the world by the year 2030. Identification of specific genetic variations in a particular ethnic group has a critical role in understanding the risk of developing T2DM in a much efficient way in future. These genetic variations include numerous types of polymorphisms among which single nucleotide polymorphisms (SNPs) is the most frequent. SNPs are basically located within the regulatory elements of several gene sequences. There are scores of genes interacting with various environmental factors affecting various pathways and sometimes even the whole signalling network that cause diseases like T2DM. This review discusses the biomarkers for early risk prediction of T2DM. Such predictions could be used in order to understand the pathogenesis of T2DM and to better diagnostics, treatment, and eventually prevention. PMID:24156506

  5. AB068. Association between MTHFR C677T and carotid intima medial thickness progression in post-ischemic stroke patient

    PubMed Central

    Pramukarso, Dodik Tugasworo; Faradz, Sultana MH; Sari, Stefani Harum; Hadisaputro, Suharyo

    2015-01-01

    Background and objective Substitution of c.677C > T in methylenetetrahydrofolate reductase (MTHFR) gene contributes to increase blood level of homocysteine (Hcy). Hyperhomocysteinemia is believed to have association with vascular damage leads to atherosclerosis. Defect MTHFR may influence vascular progression in post ischemic stroke. Carotid intima media thickness (c-IMT) has been known as vascular marker for atherosclerosis and predictor for ischemic stroke. The study aims to determine association between MTHFR C677T and c-IMT progression in post-ischemic stroke patients. Methods Seventy one of post-ischemic stroke patients were included in epidemiological prospective observational cohort study. Genotyping MTHFR gene polymorphism was done using PCR-RFLP with HinfI restriction enzyme. Blood Hcy level was determined using enzyme immunoassay (EIA) method. Carotid duplex ultrasound was used to evaluate c-IMT in 1st, 6th, and 12th month after the onset of stroke. Results The genotype distribution of MTHFR C677T in samples was CC (81.9%), CT (13.9%) and TT (4.2%). No significant differences in mean Hcy levels between genotype TT and others (CT and CC) were identified (P=0.250). Mean c-IMT showed no significant differences between genotype TT and others at evaluation in 1st month (P=0.979), 6th month (P=0.670) and 12th month (P=0.770). All samples with genotype TT were observed to have increase c-IMT level at evaluation in 1st, 6th and 12th month. Conclusions The presence of homozygote TT of MTHFR C677T may contribute to increase c-IMT level. However, this study found no association between MTHFR C677T with hyperhomocysteinemia as well as an increase in c-IMT in post-ischemic stroke patients.

  6. Prevalence of MTHFR C677T Polymorphism in North Indian Mothers Having Babies with Trisomy 21 Down Syndrome

    ERIC Educational Resources Information Center

    Kohli, Utkarsh; Arora, Sadhna; Kabra, Madhulika; Ramakrishnan, Lakshmy; Gulati, Sheffali; Pandey, Ravindra

    2008-01-01

    Recent studies have evaluated possible links between polymorphisms in maternal folate metabolism genes and Down syndrome. Some of these studies show a significantly increased prevalence of the C677T polymorphism of the 5,10-methylene tetrahydrofolate reductase (NADPH) gene (MTHFR) among mothers who have had babies with Down syndrome. This study…

  7. Prevalence of MTHFR C677T Polymorphism in North Indian Mothers Having Babies with Trisomy 21 Down Syndrome

    ERIC Educational Resources Information Center

    Kohli, Utkarsh; Arora, Sadhna; Kabra, Madhulika; Ramakrishnan, Lakshmy; Gulati, Sheffali; Pandey, Ravindra

    2008-01-01

    Recent studies have evaluated possible links between polymorphisms in maternal folate metabolism genes and Down syndrome. Some of these studies show a significantly increased prevalence of the C677T polymorphism of the 5,10-methylene tetrahydrofolate reductase (NADPH) gene (MTHFR) among mothers who have had babies with Down syndrome. This study…

  8. A common haplotype for the 677T thermolabile variant of the 5,10-methylenetetrahydrofolate reductase gene in thrombophilic patients and controls.

    PubMed

    Linnebank, M; Homberger, A; Nowak-Göttl, U; Koch, H G

    2002-12-01

    The common polymorphic transition 677C>T in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene causes a thermolabile enzyme variant. This variant is associated with moderate hyperhomocysteinemia, a risk factor for vascular disease and thrombophilia. Up to now, it remained unclear if the thermolabile MTHFR variant either directly predisposes to vascular disease, or if 677T is only a genetic marker for another causative genetic alteration in cis. Aim of this study was to characterize the genetic background of 677T-alleles by haplotype analysis. We analyzed 25 individuals of German descent homozygous for 677T: nine young patients, who had suffered from thromboembolic events, and 16 healthy controls. The results of this study demonstrate that the 677T alleles are associated with a common haplotype most likely due to a founder effect and that the 677T haplotype was the same in the healthy and the thrombophilic German subjects. PMID:12442281

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

    PubMed

    Liew, Siaw-Cheok; Gupta, Esha Das

    2015-01-01

    The Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is associated with various diseases (vascular, cancers, neurology, diabetes, psoriasis, etc) with the epidemiology of the polymorphism of the C677T that varies dependent on the geography and ethnicity. The 5,10-Methylenetetrahydrofolate reductase (MTHFR) locus is mapped on chromosome 1 at the end of the short arm (1p36.6). This enzyme is important for the folate metabolism which is an integral process for cell metabolism in the DNA, RNA and protein methylation. The mutation of the MTHFR gene which causes the C677T polymorphism is located at exon 4 which results in the conversion of valine to alanine at codon 222, a common polymorphism that reduces the activity of this enzyme. The homozygous mutated subjects have higher homocysteine levels while the heterozygous mutated subjects have mildly raised homocysteine levels compared with the normal, non-mutated controls. Hyperhomocysteinemia is an emerging risk factor for various cardiovascular diseases and with the increasing significance of this polymorphism in view of the morbidity and mortality impact on the patients, further prevention strategies and nutritional recommendations with the supplementation of vitamin B12 and folic acid which reduces plasma homocysteine level would be necessary as part of future health education. This literature review therefore focuses on the recent evidence-based reports on the associations of the MTHFR C677T polymorphism and the various diseases globally. PMID:25449138

  10. 32 CFR 644.391 - Predisposal conference.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Predisposal conference. 644.391 Section 644.391... ESTATE HANDBOOK Disposal Predisposal Action § 644.391 Predisposal conference. (a) Where a substantial Army installation, or portion thereof, is involved, the DE will convene a predisposal conference...

  11. The Association of the MTHFR c.1625A>C Genetic Variant with the Risk of Congenital Heart Diseases in the Chinese

    PubMed Central

    Wang, Yuting; Sun, Lei; Du, Weina; Song, Shuang; Wang, Shuo; Jiang, Weiju; Huang, Tianchu

    2015-01-01

    The purpose of this study is to investigate the association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with the risk of congenital heart diseases (CHD). The genotypes of the MTHFR genetic variant were determined by the polymerase chain reaction–restriction fragment length polymorphism and DNA sequencing methods. Our data suggested that the allelic and genotypic frequencies of CHD patients were significantly different from non-CHD controls. The MTHFR c.1625A>C genetic variant was significantly associated with the increased risk of CHD (CC vs. AA: odds ratio [OR]=2.29, 95% confidence interval [CI] 1.15–4.53, p=0.016; C vs. A: OR=1.47, 95% CI 1.11–1.96, p=0.008). Results from this study indicate that the MTHFR c.1625A>C genetic variant influences the risk of CHD in the studied population. PMID:25494855

  12. Association of MTHFR A1298C polymorphism with conotruncal heart disease.

    PubMed

    Sayin Kocakap, Beyza D; Sanli, Cihat; Cabuk, Feryal; Koc, Murat; Kutsal, Ali

    2015-10-01

    Congenital heart diseases are common congenital anomalies with 1% prevalence worldwide and are associated with significant childhood morbidity and mortality. Among a wide range of aetiologically heterogeneous conditions, conotruncal anomalies account for approximately one-third of all congenital heart defects. The aetiology of conotruncal heart diseases is complex, with both environmental and genetic causes. Hyperhomocysteinaemia, which is often accompanied by the defects of folic acid metabolism, is known to cause conotruncal heart anomalies. In this study, we have evaluated three polymorphisms in the following two hyperhomocysteinaemia-related genes: methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and nicotinamide N-methyl transferase (NNMT rs694539) in 79 children with conotruncal heart disease and 99 children without conotruncal heart disease. Genotype distribution of the MTHFR A1298C polymorphism showed a statistically significant difference between the two groups. In the case group, AC and CC genotypes were higher than the control group (p<0.05). We have found that MTHFR A1298C polymorphism is associated with conotruncal heart disease; C allele (p=0.028), AC (OR[95% CI]=2.48[1.24-4.95], p=0.010), CC (OR[95% CI]=3.01[1.16-7.83], p=0.023), and AC+CC (OR[95% CI]=2.60[1.36-4.99], p=0.004) genotypes are more frequent in the patient group. Genotype distributions of the MTHFR C677T and NNMT rs694539 polymorphisms were similar in the two groups when evaluated separately and also according to the dominant genetic model (p>0.05). Our results suggest that MTHFR 1298C allele is a risk factor for conotruncal heart disease. PMID:25547204

  13. The MTHFR C677T Variant is Associated with Responsiveness to Disulfiram Treatment for Cocaine Dependency

    PubMed Central

    Spellicy, Catherine J.; Kosten, Thomas R.; Hamon, Sara C.; Harding, Mark J.; Nielsen, David A.

    2013-01-01

    Objective: Disulfiram is a one of the few pharmacotherapies for cocaine addiction that shows promise. Since disulfiram and cocaine both affect levels of global methylation we hypothesized the MTHFR gene, whose product is involved in supplying methyl groups for DNA and protein methylation, may be associated with responsiveness to disulfiram in cocaine-dependent individuals. Methods: Sixty-seven cocaine-dependent patients were stabilized on methadone for 2?weeks and then randomized into disulfiram (250?mg/day, N?=?32) and placebo groups (N?=?35) for 10?weeks. Patients were genotyped for the MTHFR (rs1801133, also known as C677T) polymorphism and the data was evaluated for association with cocaine-free urines in the disulfiram or placebo groups. Data from patients that completed all 10?weeks of the study (N?=?56) were analyzed using repeated measures analysis of variance (ANOVA), corrected for population structure. Results: The CT or TT MTHFR genotype group (N?=?32) dropped from 73 to 52% cocaine-positive urines on disulfiram (p?=?0.0001), while the placebo group showed no treatment effect. The CC MTHFR genotype group (N?=?24) showed a smaller, but still significant, reduction in cocaine-positive urines on disulfiram compared to placebo; 81–69% (p?=?0.007). Conclusion: This study indicates that a patient’s MTHFR genotype may be used to identify individuals who might show improved response to disulfiram treatment for cocaine dependence. Clinical Trial: Pharmacogenetics of Disulfiram for Cocaine, clinicaltrials.gov/ct2/show/NCT00149630, NIDA-18197-2, NCT00149630. PMID:23335901

  14. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and high plasma homocysteine in chronic hepatitis C (CHC) infected patients from the Northeast of Brazil

    PubMed Central

    2011-01-01

    Background/Aim Hyperhomocysteinemia due to Methylenetetrahydrofolate Reductase (MTHFR) gene, in particular the C677T (Ala222Val) polymorphism were recently associated to steatosis and fibrosis. We analyzed the frequency of MTHFR gene in a cross-sectional study of patients affected by Chronic Hepatitis C (CHC) from Northeast of Brazil. Method One hundred seven-four untreated patients with CHC were genotyped for the C677T MTHFR. Genomic DNA was extracted from peripheral blood cells and the C677T MTHFR polymorphism was identified by PCR-RFLP. The homocysteine (Hcy) levels were determined by chemiluminescence method. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and have current and past daily alcohol intake less than 100 g/week. Results Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8% versus 4.4% genotype 1 (p = 0.01). Nevertheless, association was found between the MTHFR genotype TT × CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p < 0.05). A significant difference was found on plasma Hcy levels in patients with steatosis regardless of HCV genotype (p = 0.03). Conclusion Our results indicate that plasma Hcy levels is highly prevalent in subjects with chronic hepatits C with steatosis regardless of HCV genotype and vitamin deficiency. The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype TT+CT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis in CHC infected patients from the northeast of Brazil regardless of HCV genotype. The genetic susceptibility of MTHFR C677T polymorphism should be confirmed in a large population. PMID:21854603

  15. Capturing the biological impact of CDKN2A and MC1R genes as an early predisposing event in melanoma and non melanoma skin cancer

    PubMed Central

    Puig-Butille, Joan Anton; Escámez, María José; Garcia-Garcia, Francisco; Tell-Marti, Gemma; Fabra, Àngels; Martínez-Santamaría, Lucía; Badenas, Celia; Aguilera, Paula; Pevida, Marta; Dopazo, Joaquín; del Río, Marcela; Puig, Susana

    2014-01-01

    Germline mutations in CDKN2A and/or red hair color variants in MC1R genes are associated with an increased susceptibility to develop cutaneous melanoma or non melanoma skin cancer. We studied the impact of the CDKN2A germinal mutation p.G101W and MC1R variants on gene expression and transcription profiles associated with skin cancer. To this end we set-up primary skin cell co-cultures from siblings of melanoma prone-families that were later analyzed using the expression array approach. As a result, we found that 1535 transcripts were deregulated in CDKN2A mutated cells, with over-expression of immunity-related genes (HLA-DPB1, CLEC2B, IFI44, IFI44L, IFI27, IFIT1, IFIT2, SP110 and IFNK) and down-regulation of genes playing a role in the Notch signaling pathway. 3570 transcripts were deregulated in MC1R variant carriers. In particular, genes related to oxidative stress and DNA damage pathways were up-regulated as well as genes associated with neurodegenerative diseases such as Parkinson’s, Alzheimer and Huntington. Finally, we observed that the expression signatures indentified in phenotypically normal cells carrying CDKN2A mutations or MC1R variants are maintained in skin cancer tumors (melanoma and squamous cell carcinoma). These results indicate that transcriptome deregulation represents an early event critical for skin cancer development. PMID:24742402

  16. Significant Impact of the MTHFR Polymorphisms and Haplotypes on Male Infertility Risk

    PubMed Central

    Gupta, Nishi; Sarkar, Saumya; David, Archana; Gangwar, Pravin Kumar; Gupta, Richa; Khanna, Gita; Sankhwar, Satya Narayan; Khanna, Anil; Rajender, Singh

    2013-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) converts 5,10-methylene tetrahydrofolate to 5-methyl tetrahydrofolate and affects the activity of cellular cycles participating in nucleotide synthesis, DNA repair, genome stability, maintenance of methyl pool, and gene regulation. Genetically compromised MTHFR activity has been suggested to affect male fertility. The objective of the present study was to find the impact on infertility risk of c.203G>A, c.1298A>C, and c.1793G>A polymorphisms in the MTHFR gene. Methods PCR-RFLP and DNA sequencing were used to genotype the common SNPs in the MTHFR gene in 630 infertile and 250 fertile males. Chi-square test was applied for statistical comparison of genotype data. Linkage disequilibrium between the SNPs and the frequency of common haplotypes were assessed using Haploview software. Biochemical levels of total homocysteine (tHcy) and folic acid were measured. Meta-analysis on c.1298A>C polymorphism was performed using data from ten studies, comprising 2734 cases and 2737 controls. Results c.203G>A and c.1298A>C were found to be unrelated to infertility risk. c.1793G>A was protective against infertility (P?=?0.0008). c.677C>T and c.1793G>A were in significant LD (D’?=?0.9). Folic acid and tHcy level did not correlate with male infertility. Pooled estimate on c.1298A>C data from all published studies including our data showed no association of this polymorphism with male infertility (Odds ratio?=?1.035, P?=?0.56), azoospermia (Odds ratio?=?0.97, P?=?0.74), or oligoasthenoteratozoospermia (Odds ratio?=?0.92, p?=?0.29). Eight haplotypes with more than 1% frequency were detected, of which CCGA was protective against infertility (p?=?0.02), but the significance of the latter was not seen after applying Bonferroni correction. Conclusion Among MTHFR polymorphisms, c.203G>A and c.1298A>C do not affect infertility risk and c.1793G>A is protective against infertility. Haplotype analysis suggested that risk factors on the MTHFR locus do not extend too long on the DNA string. PMID:23874907

  17. Association of MTHFR genetic polymorphisms with venous thromboembolism in Uyghur population in Xinjiang, China

    PubMed Central

    Li, Zhao; Yadav, Umesh; Mahemuti, Ailiman; Tang, Bao-Peng; Upur, Halmurat

    2015-01-01

    Background: The aim of this study was to reveal the association between Methylene tetrahydrofolate reductase (MTHFR) gene mutations (C677T, A1298C and C1317T) and risk of venous thromboembolism (VTE) in Han and Uyghur population in Xinjiang. Material and method: We conducted a case control study composed of 246 cases, including 86 Uyghur and 160 Han ethnic diagnosed VTE were admitted in the First Affiliated Hospital of Xinjiang Medical University between January 2008 to December 2012, and 292 population including 122 Uyghur ethnic and 170 Han ethnic were studied as controls. To detect the polymorphism of MTHFR gene C677T, A1298T, and C1317T, Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied. Fluorescence polarization immunoassay was adopted to determine the plasma levels Homocysteine (Hcy), folic acid and vitaminB12 (VitB12). The association of the polymorphism of MTHFR and levels Hcy, folic acid and VitB12 with VTE was analyzed. Results: The MTHFR gene C677T genotypes distribution in Uyghur VTE patients and control groups were: TT (27.91% vs. 12.29%), CT (41.86% vs. 52.46%) and CC (30.23% vs. 35.25%), respectively; and in Han VTE patients and control groups were: TT (27.49% vs. 14.71%), CT (44.38% vs. 53.53%) and CC (28.13% vs. 31.76%), respectively, and there were significant differences in TT genotype of MTHFRC677T between VTE patients and controls in both Uyghur and Han ethnic (Uyghur: x2=8.070, P=0.005; Han: x2=8.159, P=0.004). However, there were no significant differences in the MTHFR gene A1298T and C1317T genotyping distribution frequency in Uygur and Han ethnic between VTE patients and controls (P>0.05). Plasma levels of Hcy in MTHFR gene TT genotype were statistically higher than CT and CC genotype (P<0.05). After adjusting for age, gender, smoking, hypertension, hyperlipidemia, diabetes and MTHFR genotype for plasma Hcy levels, multifactor logistic regression analysis showed (OR=1.025, 95% CI 1.003-1.046, P=0.024) and obesity (OR=4.660, 95% CI 1.417-15.324, P=0.011) were independent risk factors for Uygur ethnic with VTE while plasma Hcy levels (OR=1.020, 95% CI 1.006-1.034, P=0.004) and smoking (OR=2.867, 95% CI 1.062-6.586, P=0.024) were independent risk factors for Han ethnic with VTE. Conclusions: Our finding supports significant role of MTHFR gene in VTE and evidence of genetically determined HHcy contribute a risk for VTE, and a smoker with tHcy has positive association with a risk of VTE. PMID:26770360

  18. High-Resolution Array CGH Profiling Identifies Na/K Transporting ATPase Interacting 2 (NKAIN2) as a Predisposing Candidate Gene in Neuroblastoma

    PubMed Central

    Romania, Paolo; Castellano, Aurora; Surace, Cecilia; Citti, Arianna; De Ioris, Maria Antonietta; Sirleto, Pietro; De Mariano, Marilena; Longo, Luca; Boldrini, Renata; Angioni, Adriano; Locatelli, Franco; Fruci, Doriana

    2013-01-01

    Neuroblastoma (NB), the most common solid cancer in early childhood, usually occurs sporadically but also its familial occurance is known in 1-2% of NB patients. Germline mutations in the ALK and PHOX2B genes have been found in a subset of familial NBs. However, because some individuals harbouring mutations in these genes do not develop this tumor, additional genetic alterations appear to be required for NB pathogenesis. Herein, we studied an Italian family with three NB patients, two siblings and a first cousin, carrying an ALK germline-activating mutation R1192P, that was inherited from their unaffected mothers and with no mutations in the PHOX2B gene. A comparison between somatic and germline DNA copy number changes in the two affected siblings by a high resolution array-based Comparative Genomic Hybridization (CGH) analysis revealed a germline gain at NKAIN2 (Na/K transporting ATPase interacting 2) locus in one of the sibling, that was inherited from the parent who does not carry the ALK mutation. Surprisingly, NKAIN2 was expressed at high levels also in the affected sibling that lacks the genomic gain at this locus, clearly suggesting the existance of other regulatory mechanisms. High levels of NKAIN2 were detected in the MYCN-amplified NB cell lines and in the most aggressive NB lesions as well as in the peripheral blood of a large cohort of NB patients. Consistent with a role of NKAIN2 in NB development, NKAIN2 was down-regulated during all-trans retinoic acid differentiation in two NB cell lines. Taken together, these data indicate a potential role of NKAIN2 gene in NB growth and differentiation. PMID:24205241

  19. Risk association of meningiomas with MTHFR C677T and GSTs polymorphisms: a meta-analysis.

    PubMed

    Ding, Hao; Liu, Wei; Yu, Xinyuan; Wang, Lei; Shao, Lingmin; Yi, Wei

    2014-01-01

    Previous studies have shown that the single nucleotide polymorphisms (SNPs) in Methylenetetrahydrofolate reductase (MTHFR) and Glutathione S-transferases (GSTs, including GSTM1, GSTT1) genes play an important role in determining the response of an individual to environmental pathogenesis and significantly relate to incidences of various human tumors, including brain tumors. However, these genes' polymorphisms on meningioma risk remains poorly understood. The relevant inferences from previous studies are hindered by their limited statistical power and conflicting results. The aim of this meta-analysis is to provide a relatively comprehensive account of the association between these polymorphisms and human meningioma risk. A literature search for eligible studies published before January 1, 2014 was conducted in PubMed, Embase, Web of Science, Cochrane Library, and CNKI databases. Pooled odds ratios (OR) with their corresponding 95% confidence intervals (95% CI) were used to evaluate the strength of the association under a fixed or random effect model according to heterogeneity test results. Heterogeneity and publication bias were evaluated. All statistical analyses were conducted by using the software of STATA 12.0 (STATA Corporation, College Station, TX, USA). For MTHFR C677T (dbSNP: rs1801133) (C T) polymorphism, 9 individual case-control studies from six publications with 1,615 cases and 1,909 controls were obtained. For GSTM1 null polymorphism, there were 4 studies with 417 cases and 1,735 controls. For GSTT1 null polymorphism, there were 4 studies with 405 cases and 1,622 controls. The combined results for the MTHFR C677T show that carriers of the CT genotype may be associated with a higher meningioma risk (OR = 1.20, 95% CI 1.05-1.38, P = 0.009). Stratified analyses show that Caucasians have significantly higher risk if they carry the CT genotype of MTHFR (OR = 1.31, 95% CI 1.05-1.63, P = 0.02). Risk of Caucasians carrying TT + CT genotype is also significantly higher (OR = 1.27, 95% CI 1.02-1.58, P = 0.03). Risk of Caucasians carrying TT genotype is not significantly different compared to control population (OR = 0.96, 95% CI 0.69-1.34, P = 0.82). All of the enrolled studies about GSTM1/GSTT1 are on Caucasians. The pooled ORGSTM1 and ORGSTT1 were not significant in Caucasian population. These results indicate SNPs of MTHFR C677T are related to meningioma risk with ethnic differences. Caucasians carrying CT genotype of MTHFR C677T have significantly higher meningioma susceptibility. SNPs of GSTM1/GSTT1 are not related to meningioma risk. PMID:25550898

  20. The methylenetetrahydrofolate reductase (MTHFR) 677 C>T polymorphism increases the risk of developing chronic myeloid leukemia-a case-control study.

    PubMed

    B?nescu, Claudia; Iancu, Mihaela; Trifa, Adrian P; Macarie, Ioan; Dima, Delia; Dobreanu, Minodora

    2015-04-01

    The methylenetetrahydrofolate reductase (MTHFR) 677 C>T and 1298 A>C polymorphisms are associated with variations in folate levels, a phenomenon linked to the development of various malignancies. The aim of this study was to investigate the influence of the 677 C>T and 1298 A>C polymorphisms in the MTHFR gene on the risk of developing chronic myeloid leukemia (CML). Our study included 151 patients with CML and 305 controls. The MTHFR 677 C>T and 1298 A>C polymorphisms were investigated by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and allele-specific PCR techniques. The CT and TT genotypes of the MTHFR 677 C>T polymorphism were associated with an increased risk of developing CML (odds ratio (OR)?=?1.556, 95% confidence interval (CI)?=?1.017-2.381, p value?=?0.041, and OR?=?1.897, 95% CI?=?1.046-3.44, p value?=?0.035, respectively). No association was observed between the prognostic factors (blasts, basophils, additional chromosomal abnormalities, EUTOS score, Sokal and Hasford risk groups) and the MTHFR 677 C>T and 1298 A>C variant genotypes in CML patients. Our study shows that the MTHFR 677 C>T polymorphism is significantly associated with the risk of CML in Romanian patients. PMID:25510667

  1. Effect of methotrexate on the survival of human lymphocyte cultures carrying MTHFR 677 (C>T) and MTHFR 1298 (A>C) mutations.

    PubMed

    Al-Refai, Ekhlas A; Sadiq, May F; Khassawneh, Mohammad Y; Amjad D, Al-Nasser

    2009-01-01

    The correlations between the presence of MTHFR 677 (C>T) and MTHFR 1298 (A>C) mutations in human lymphocytes and the sensitivity of lymphocytes to methotrexate (MTX) were examined in cultures derived from 82 unrelated women, genotyped for these mutations by polymerase chain reaction-restriction fragment length polymorphism. Lymphocytes heterozygous for the mutant allele, MTHFR 677T, were significantly more sensitive to methotrexate than those carrying the homozygous wild-type allele, MTHFR677C, and those carrying either the mutant or the wild-type alleles in the polymorphic MTHFR 1298 site. In addition, the lymphocyte cultures carrying the mutant MTHFR 1298C allele were not different in their sensitivity to MTX from those cultures carrying the wild-type allele, MTHFR 1298A. This demonstrated that the polymorphic site MTHFR C677, but not MTHFR1298, could be considered as a useful pharmacogenetic determinant in planning and designing the effective personal MTX chemotherapeutic doses and regimes. PMID:19514945

  2. Recent developments in brain tumor predisposing syndromes.

    PubMed

    Johansson, Gunnar; Andersson, Ulrika; Melin, Beatrice

    2016-04-01

    The etiologies of brain tumors are in the most cases unknown, but improvements in genetics and DNA screening have helped to identify a wide range of brain tumor predisposition disorders. In this review we are discussing some of the most common predisposition disorders, namely: neurofibromatosis type 1 and 2, schwannomatosis, rhabdoid tumor predisposition disorder, nevoid basal cell carcinoma syndrome (Gorlin), tuberous sclerosis complex, von Hippel-Lindau, Li-Fraumeni and Turcot syndromes. Recent findings from the GLIOGENE collaboration and the newly identified glioma causing gene POT1, will also be discussed. Genetics. We will describe these disorders from a genetic and clinical standpoint, focusing on the difference in clinical symptoms depending on the underlying gene or germline mutation. Central nervous system (CNS) tumors. Most of these disorders predispose the carriers to a wide range of symptoms. Herein, we will focus particularly on tumors affecting the CNS and discuss improvements of targeted therapy for the particular disorders. PMID:26634384

  3. Genes and Environment as Predisposing Factors in Autoimmunity: Acceleration of Spontaneous Thyroiditis by Dietary Iodide in NOD.H2(h4) Mice.

    PubMed

    Kolypetri, Panayota; King, Justin; Larijani, Mani; Carayanniotis, George

    2015-11-01

    In the field of autoimmune thyroiditis, NOD.H2(h4) mice have attracted significant and increasing attention since they not only develop spontaneous disease but they present thyroiditis with accelerated incidence and severity if they ingest iodide through their drinking water. This animal model highlights the interplay between genetic and dietary factors in the triggering of autoimmune disease and offers new opportunities to study immunoregulatory parameters influenced by both genes and environment. Here, we review experimental findings with this mouse model of thyroiditis. PMID:26287317

  4. MTHFR 677C>T Polymorphism Increases the Male Infertility Risk: A Meta-Analysis Involving 26 Studies

    PubMed Central

    Gong, Mancheng; Dong, Wenjing; He, Tingyu; Shi, Zhirong; Huang, Guiying; Ren, Rui; Huang, Sichong; Qiu, Shaopeng; Yuan, Runqiang

    2015-01-01

    Background and Objectives Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy. Methods Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk. Results Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23–1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19–1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant association was only observed in oligo subgroup. Conclusions Our results indicated that the MTHFR polymorphism is associated with an increased risk of male infertility. Further well-designed analytical studies are necessary to confirm our conclusions and evaluate gene-environment interactions with male infertility risk. PMID:25793386

  5. Association of common variants in/near six genes (ATP2B1, CSK, MTHFR, CYP17A1, STK39 and FGF5) with blood pressure/hypertension risk in Chinese children.

    PubMed

    Xi, B; Shen, Y; Zhao, X; Chandak, G R; Cheng, H; Hou, D; Li, Y; Ott, J; Zhang, Y; Wang, X; Mi, J

    2014-01-01

    Recent genome-wide association studies have identified several single-nucleotide polymorphisms (SNPs) that are associated with blood pressure (BP)/hypertension. In this study, we aimed to examine the established associations amongst Chinese children. We genotyped six SNPs (ATP2B1 rs17249754, CSK rs1378942, MTHFR rs1801133, CYP17A1 rs1004467, STK39 rs3754777 and FGF5 rs16998073) in Chinese children (N=3077, age range, 6-18 years). Based on the Chinese age- and sex-specific BP standards, 619 hypertensive cases and 2458 controls with normal BP were identified. Of the six SNPs, only ATP2B1 rs17249754 SNP was significantly associated with the risk of hypertension (allelic odds ratio (OR)=1.25, 95% confidence interval (CI): 1.08-1.44, P=0.003). Although all other SNPs showed a trend towards increasing the BP values and risk of hypertension, there was no statistically significant association after false discovery rate analysis. We calculated the weighted risk score using six SNPs, for systolic BP (SBP), diastolic BP (DBP) and hypertension. Each additional weighted risk score was associated with SBP by 1.18 mm Hg (95% CI=0.62-1.73, P<0.001), but not with the DBP (?=0.28, 95% CI=(-0.15)-0.74), and overall increased the risk of hypertension by 1.19-fold (95% CI=1.04-1.35, P=0.01). The present study confirmed the significant association of ATP2B1 rs17249754 with risk of hypertension among Chinese children, but failed to replicate the association of CSK rs1378942, MTHFR rs1801133, CYP17A1 rs1004467, STK39 rs3754777 and FGF5 rs16998073 with BP/risk of hypertension. PMID:23759979

  6. Polymorphisms in catechol-O-methyltransferase and cytochrome p450 subfamily 19 genes predispose towards Madurella mycetomatis-induced mycetoma susceptibility.

    PubMed

    van de Sande, Wendy W J; Fahal, Ahmed; Tavakol, Mehri; van Belkum, Alex

    2010-11-01

    Mycetoma caused by Madurella mycetomatis is a devastating and neglected disease which primarily affects males. Since this predominance cannot be easily explained by behaviour differences between men and women, other factors, including sex hormones, could be the cause. To monitor for possible deficiencies in hormone synthesis among mycetoma patients, we investigated the types and allele frequencies of the genes encoding for catechol-O-methyltransferase (COMT), cytochrome p450 subfamily 1 (CYP1B1), cytochrome p450 subfamily 17 (CYP17), cytochrome p450 subfamily 19 (CYP19) and hydroxysteroid dehydrogenase 3B (HSD3B). Significant differences in allele distribution were demonstrated for CYP19 (P=0.004) and COMT (P=0.005), as well as gender dimorphism for both CYP19 and COMT polymorphisms. The COMT polymorphism was associated with lesion size. The genotypes obtained for COMT and CYP19 were connected with higher 17?-estradiol production, which was confirmed by significantly elevated serum levels of 17?-estradiol in male patients. In contrast, lowered levels of dehydroepiandrosteron (DHEA) were found in mycetoma patients. The in vitro growth of M. mycetomatis was not influenced by 17?-estradiol, progesterone, DHEA and testosterone. The differences in hormone levels we noted between mycetoma patients and healthy controls did not directly affect the fungus itself. Indirect effects on the patients' hormone regulated immune states are the more likely explanations for mycetoma susceptibility. PMID:20184498

  7. Contribution of GSTM1, GSTT1, and MTHFR polymorphisms to end-stage renal disease of unknown etiology in Mexicans.

    PubMed

    Gutiérrez-Amavizca, B E; Orozco-Castellanos, R; Ortíz-Orozco, R; Padilla-Gutiérrez, J; Valle, Y; Gutiérrez-Gutiérrez, N; García-García, G; Gallegos-Arreola, M; Figuera, L E

    2013-11-01

    Oxidative stress is increased in chronic kidney disease, owing to an imbalance between the oxidative and antioxidant pathways as well as a state of persistent hyperhomocysteinemia. The enzymes glutathione S-transferases (GSTs) and methylenetetrahydrofolate reductase (MTHFR) are implicated in the regulation of these pathways. This study investigates the association between polymorphisms in the Glutathione S-transferase Mu 1 (GSTM1), glutathione S-transferase theta 1 (GSTT1), and MTHFR genes and end-stage renal disease (ESRD) of unknown etiology in patients in Mexico. A Case-control study included 110 ESRD patients and 125 healthy individuals. GSTM1 and GSTT1 genotypes were determined using the multiplex polymerase chain reaction (PCR). The MTHFR C677T polymorphism was studied using a PCR/restriction fragment length polymorphism method. In ESRD patients, GSTM1 and GSTT1 null genotype frequencies were 61% and 7% respectively. GSTM1 genotype frequencies differed significantly between groups, showing that homozygous deletion of the GSTM1 gene was associated with susceptibility to ESRD of unknown etiology (P = 0.007, odds ratios = 2.05, 95% confidence interval 1.21-3.45). The MTHFR C677T polymorphism genotype and allele distributions were similar in both groups (P > 0.05), and the CT genotype was the most common genotype in both groups (45.5% and 46.6%). Our findings suggest that the GSTM1 null polymorphism appears to be associated with the ESRD of unknown etiology in patients in Mexico. PMID:24339523

  8. A common haplotype in the complement regulatory gene factor H (HF1/CFH) predisposes individuals to age-related macular degeneration

    PubMed Central

    Hageman, Gregory S.; Anderson, Don H.; Johnson, Lincoln V.; Hancox, Lisa S.; Taiber, Andrew J.; Hardisty, Lisa I.; Hageman, Jill L.; Stockman, Heather A.; Borchardt, James D.; Gehrs, Karen M.; Smith, Richard J. H.; Silvestri, Giuliana; Russell, Stephen R.; Klaver, Caroline C. W.; Barbazetto, Irene; Chang, Stanley; Yannuzzi, Lawrence A.; Barile, Gaetano R.; Merriam, John C.; Smith, R. Theodore; Olsh, Adam K.; Bergeron, Julie; Zernant, Jana; Merriam, Joanna E.; Gold, Bert; Dean, Michael; Allikmets, Rando

    2005-01-01

    Age-related macular degeneration (AMD) is the most frequent cause of irreversible blindness in the elderly in developed countries. Our previous studies implicated activation of complement in the formation of drusen, the hallmark lesion of AMD. Here, we show that factor H (HF1), the major inhibitor of the alternative complement pathway, accumulates within drusen and is synthesized by the retinal pigmented epithelium. Because previous linkage analyses identified chromosome 1q25-32, which harbors the factor H gene (HF1/CFH), as an AMD susceptibility locus, we analyzed HF1 for genetic variation in two independent cohorts comprised of ≈900 AMD cases and 400 matched controls. We found association of eight common HF1 SNPs with AMD; two common missense variants exhibit highly significant associations (I62V, χ2 = 26.1 and P = 3.2 × 10-7 and Y402H, χ2 = 54.4 and P = 1.6 × 10-13). Haplotype analysis reveals that multiple HF1 variants confer elevated or reduced risk of AMD. One common at-risk haplotype is present at a frequency of 50% in AMD cases and 29% in controls [odds ratio (OR) = 2.46, 95% confidence interval (1.95-3.11)]. Homozygotes for this haplotype account for 24% of cases and 8% of controls [OR = 3.51, 95% confidence interval (2.13-5.78)]. Several protective haplotypes are also identified (OR = 0.44-0.55), further implicating HF1 function in the pathogenetic mechanisms underlying AMD. We propose that genetic variation in a regulator of the alternative complement pathway, when combined with a triggering event, such as infection, underlie a major proportion of AMD in the human population. PMID:15870199

  9. Association of the Maternal MTHFR C677T Polymorphism with Susceptibility to Neural Tube Defects in Offsprings: Evidence from 25 Case-Control Studies

    PubMed Central

    Zou, Peng; Ji, Guixiang; Gu, Aihua; Zhao, Peng

    2012-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA methylation, DNA synthesis, and DNA repair. In addition, it is a possible risk factor in neural tube defects (NTDs). The association of the C677T polymorphism in the MTHFR gene and NTD susceptibility has been widely demonstrated, but the results remain inconclusive. In this study, we performed a meta-analysis with 2429 cases and 3570 controls to investigate the effect of the MTHFR C677T polymorphism on NTDs. Methods An electronic search of PubMed and Embase database for papers on the MTHFR C677T polymorphism and NTD risk was performed. All data were analysed with STATA (version 11). Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. Sensitivity analysis, test of heterogeneity, cumulative meta-analysis, and assessment of bias were performed in our meta-analysis. Results A significant association between the MTHFR C677T polymorphism and NTD susceptibility was revealed in our meta-analysis ( TT versus CC: OR ?=?2.022, 95% CI: 1.508, 2.712; CT+TT versus CC: OR ?=?1.303, 95% CI: 1.089, 1.558; TT versus CC+CT: OR ?=?1.716, 95% CI: 1.448, 2.033; 2TT+CT versus 2CC+CT: OR ?=?1.330, 95% CI: 1.160, 1.525). Moreover, an increased NTD risk was found after stratification of the MTHFR C677T variant data by ethnicity and source of controls. Conclusion The results suggested the maternal MTHFR C677T polymorphism is a genetic risk factor for NTDs. Further functional studies to investigate folate-related gene polymorphisms, periconceptional multivitamin supplements, complex interactions, and the development of NTDs are warranted. PMID:23056169

  10. High homocysteine and epistasis between MTHFR and APOE: association with cognitive performance in the elderly.

    PubMed

    Polito, Letizia; Poloni, Tino Emanuele; Vaccaro, Roberta; Abbondanza, Simona; Mangieri, Michela; Davin, Annalisa; Villani, Simona; Guaita, Antonio

    2016-04-01

    High total homocysteine (tHcy) is associated with cognitive impairment in the elderly. The impact of high tHcy on different cognitive domains deserves further investigation, as does the role of the C677T polymorphism of the 5,10 methylenetetrahydrofolate reductase (MTHFR) gene. A cross-sectional analysis of 903 subjects from the population-based "InveCe.Ab" study was performed. The participants had no psychosis or active neurological disorders. They underwent a neuropsychological assessment. Principal component analysis allowed cognitive performance to be condensed into two components: executive functions and memory. Novel components were evaluated for association with tHcy, controlling for potential confounders. Regression models showed that high serum tHcy was associated with lower executive functions, but not with memory. MTHFR C677T TT was associated with higher tHcy but did not affect cognitive performance per se. However, when combined with the apolipoprotein E (APOE)-ε4 allele, it was a risk factor for lower executive performance, independently of tHcy levels. In summary, high tHcy per se, or MTHFR C677T TT in combination with the APOE-ε4 allele, might be associated primarily with executive dysfunctions rather than memory loss. PMID:26774227

  11. MTHFR polymorphisms in gastric cancer and in first-degree relatives of patients with gastric cancer.

    PubMed

    De Re, Valli; Cannizzaro, R; Canzonieri, V; Cecchin, E; Caggiari, L; De Mattia, E; Pratesi, C; De Paoli, P; Toffoli, G

    2010-01-01

    Two common mutations, 677 C-->T and a1298 A-->C, in the methylenetetrahydrofolate reductase gene (MTHFR) reduce the activity of MTHFR and folate metabolism. Familial aggregation in a variable but significant proportion of gastric cancer (GC) cases suggests the importance of genetic predisposition in determining risk. In this study, we evaluate MTHFR polymorphisms in 57 patients with a diagnosis of GC, in 37 with a history of GC in first-degree relatives (GC-relatives), and in 454 blood donors. Helicobacter pylori (HP) infection was also determined. An increased risk was found for 677TT in GC patients with respect to blood donors (odds ratio (OR) = 1.98), and statistical significance was sustained when we compared sex-age-matched GC patients and donors (OR = 2.37). The 677TT genotype association with GC was found in women (OR = 3.10), while a reduction in the 667C allele frequency was present in both the sex. No statistically significant association was detected when 677-1298 genotype was stratified by sex and age. Men of GC-relatives showed a higher 1298C allele frequency than donors (OR = 4.38). Between GC and GC-relatives, HP infection frequency was similar. In conclusion, overall findings support the hypothesis that folate plays a role in GC risk. GC-relatives evidence a similar 677TT frequency to that found in the general population. PMID:20237899

  12. Folate intake, MTHFR genotype, and sex modulate choline metabolism in mice.

    PubMed

    Chew, Tina W; Jiang, Xinyin; Yan, Jian; Wang, Wei; Lusa, Amanda L; Carrier, Bradley J; West, Allyson A; Malysheva, Olga V; Brenna, J Thomas; Gregory, Jesse F; Caudill, Marie A

    2011-08-01

    Choline and folate are interrelated in 1-carbon metabolism, mostly because of their shared function as methyl donors for homocysteine remethylation. Folate deficiency and mutations of methylenetetrahydrofolate reductase (MTHFR) reduce the availability of a major methyl donor, 5-methyltetrahydrofolate, which in turn may lead to compensatory changes in choline metabolism. This study investigated the hypothesis that reductions in methyl group supply, either due to dietary folate deficiency or Mthfr gene deletion, would modify tissue choline metabolism in a sex-specific manner. Mthfr wild type (+/+) or heterozygous (+/-) knockout mice were randomized to a folate-deficient or control diet for 8 wk during which time deuterium-labeled choline (d9-choline) was consumed in the drinking water (~10 ?mol/d). Mthfr heterozygosity did not alter brain choline metabolite concentrations, but it did enhance their labeling in males (P < 0.05) and tended to do so in females (P < 0.10), a finding consistent with greater turnover of dietary choline in brains of +/- mice. Dietary folate deficiency in females yielded 52% higher (P = 0.027) hepatic glycerophosphocholine, which suggests that phosphatidylcholine (PtdCho) degradation was enhanced. Labeling of the hepatic PtdCho in d3 form was also reduced (P < 0.001) in females, which implies that fewer of the dietary choline-derived methyl groups were used for de novo PtdCho biosynthesis under conditions of folate insufficiency. Males responded to folate restriction with a doubling (P < 0.001) of hepatic choline dehydrogenase transcripts, a finding consistent with enhanced conversion of choline to the methyl donor, betaine. Collectively, these data show that several adaptations in choline metabolism transpire as a result of mild perturbations in folate metabolism, presumably to preserve methyl group homeostasis. PMID:21697299

  13. Methotrexate consolidation treatment according to pharmacogenetics of MTHFR ameliorates event-free survival in childhood acute lymphoblastic leukaemia.

    PubMed

    Salazar, J; Altés, A; del Río, E; Estella, J; Rives, S; Tasso, M; Navajas, A; Molina, J; Villa, M; Vivanco, J L; Torrent, M; Baiget, M; Badell, I

    2012-10-01

    Recent advances in treatment for childhood acute lymphoblastic leukaemia (ALL) have significantly increased outcome. High-dose methotrexate (MTX) is the most commonly used regimen during the consolidation period, but the optimal dose remains to be defined. We investigated the usefulness of the MTHFR genotype to increase the MTX dosage in the consolidation phase in 141 childhood ALL patients enrolled in the ALL/SHOP-2005 protocol. We also investigated the pharmacogenetic role of polymorphisms in genes involved in MTX metabolism on therapy-related toxicity and survival. Patients with a favourable MTHFR genotype (normal enzymatic activity) treated with MTX doses of 5?g?m?² had a significantly lower risk of suffering an event than patients with an unfavourable MTHFR genotype (reduced enzymatic activity) that were treated with the classical MTX dose of 3?g?m?² (P=0.012). Our results indicate that analysis of the MTHFR genotype is a useful tool to optimise MTX therapy in childhood patients with ALL. PMID:21747412

  14. MTHFR C677T polymorphism and differential methylation status in gastric cancer: an association with Helicobacter pylori infection.

    PubMed

    Neves Filho, Eduardo Henrique Cunha; Alves, Markenia Kelia Santos; Lima, Valeska Portela; Rabenhorst, Silvia Helena Barem

    2010-12-01

    MTHFR C677T and Helicobacter pylori infection are believed to play critical roles in the DNA methylation process, an epigenetic feature frequently found in gastric cancer. The aim of this study was to verify the associations between the MTHFR C677T polymorphism and the methylation status of three gastric cancer-related genes. The influence of H. pylori strains was also assessed. DNA extracted from 71 gastric tumor samples was available for MTHFR C677T genotyping by PCR-RFLP, promoter methylation identification by MS-PCR and H. pylori detection and posterior subtyping (cagA and vacA genes) by PCR. In the distal tumors, a positive correlation was found between the methylation of CDKN2A and the allele T carriers (r=0.357; p=0.009). Considering the eldest patients (age ?60 years old), this correlation was even higher (r=0,417; p=0.014). H. pylori infection by highly pathogenic strains (cagA+/vacAs1m1) was also found correlated to promoter methylation of CDKN2A and the allele T carriers in distal tumors (r=0.484; p=0.026). No significant correlation was verified between MTHFR C677T genotype and promoter methylation status when we analyzed the general sample. DNA methylation in CDKN2A associated to the MTHFR 677T carrier is suggested to be a distal tumor characteristic, especially in those 60 years old or older, and it seems to depend on the infection by H. pylori cagA/vacAs1m1 strains. PMID:20957490

  15. MTHFR C677T Polymorphism is Associated with Tumor Response to Preoperative Chemoradiotherapy: A Result Based on Previous Reports

    PubMed Central

    Zhao, Yue; Li, Xingde; Kong, Xiangjun

    2015-01-01

    Background Preoperative chemoradiotherapy (pRCT) followed by surgery has been widely practiced in locally advanced rectal cancer, esophageal cancer, gastric cancer and other cancers. However, the therapy also exerts some severe adverse effects and some of the patients show poor or no response. It is very important to develop biomarkers (e.g., gene polymorphisms) to identify patients who have a higher likelihood of responding to pRCT. Recently, a series of reports have investigated the association of the genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and epidermal growth factor receptor (EGFR) genes with the tumor response to pRCT; however, the results were inconsistent and inconclusive. Material/Methods A systematic review and meta-analysis was performed by searching relevant studies about the association of MTHFR and EGFR polymorphisms with the tumor regression grade (TRG) in response to pRCT in databases of PubMed, EMBAS, Web of science, Chinese National Knowledge Infrastructure, and Wanfang database up to March 30, 2015. The pooled odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) were calculated to assess the strength of the association under 5 genetic models. Results A total of 11 eligible articles were included in the present meta-analysis, of which 8 studies were performed in rectal cancer and 3 studies were performed in esophageal cancer. We finally included 8 included studies containing 839 cases for MTHFR C677T, 5 studies involving 634 cases for MTHFR A1298C, 3 studies containing 340 cases for EGFR G497A, and 4 studies containing 396 cases for EGFR CA repeat. The pooled analysis results indicated that MTHFR C677T might be correlated with the tumor response to pRCT under the recessive model (CC vs. CTTT) in overall analysis (OR=1.426(1.074–1.894), P=0.014), rectal cancer (OR=1.483(1.102–1.996), P=0.009), and TRG 1–2 vs. 3–5 group (OR=1.423(1.046–1.936), P=0.025), while other polymorphism including MTHFR A1298C, EGFR G497A, and EGFR CA repeat polymorphisms exerted significant association under all genetic models in overall analysis or subgroup analysis. Conclusions MTHFR C677T might be correlated with the tumor response to pRCT. Further well-designed, larger-scale epidemiological studies are needed to validate our results. PMID:26456456

  16. Association of MTHFR C677T with total homocysteine plasma levels and susceptibility to Parkinson's disease: a meta-analysis.

    PubMed

    Zhu, Ying; Zhu, Rui-Xia; He, Zhi-Yi; Liu, Xu; Liu, He-Nan

    2015-06-01

    The C677T single-nucleotide polymorphism in the methylenetetrahydrofolate reductase gene (MTHFR) may elevate homocysteine (Hcy) levels and increase the risk of Parkinson's disease (PD); however, results are conflicting. Our aim was to resolve contradictions in the literature and to determine whether MTHFR C677T has a significant role in regulating Hcy levels and/or is a significant risk factor for PD. MEDLINE, EMBASE, the Cochrane Library, China Biological Medicine Database and Google Scholar were searched until May 2014. Strict selection and exclusion criteria were determined, and odds ratios (ORs)/weighted mean differences (WMDs) with 95 % confidence intervals (CIs) were used to assess the strength of associations. Statistical analyses were performed using STATA 12.0. Fifteen studies that together assessed 2690 PD cases and 8465 controls were included. Meta-analysis showed that no significant difference in the distribution of MTHFR C677T between PD cases and controls was found. While stratifying for ethnicity, significant association was revealed in Europeans (T vs. C, OR = 1.17, 95 % CIs 1.04-1.31) but not in Asians. Significant association between the T allele and increased Hcy levels was found in PD cases and controls; Hcy levels were higher in PD cases and controls carrying the MTHFR T677 allele than in non-carriers (TT vs. CC, PD WMD = 6.50, 95 % CIs 6.20-6.80; controls WMD = 4.52, 95 % CIs 4.24-4.80). Other within-group comparisons showed similar results. This meta-analysis suggests that MTHFR C667T may confer PD susceptibility in Europeans. The T allele may be an independent risk factor for elevated Hcy levels in PD patients. PMID:25564416

  17. Correlation of the C677T MTHFR genotype with homocysteine levels in children with sickle cell disease.

    PubMed

    Balasa, V V; Gruppo, R A; Gartside, P S; Kalinyak, K A

    1999-01-01

    Recently, a mild to moderate elevation in the plasma homocysteine (Hcy) level has been found to be an important risk factor for stroke. Homozygosity for a common mutation (C677T) in the gene encoding for the enzyme methylenetetrahydrofolate reductase (MTHFR) involved in Hcy metabolism has been associated with increased levels of Hcy. To determine the role of hyperhomocysteinemia in the pathogenesis of stroke in children with sickle cell disease (SCD), Hcy levels and C677T MTHFR genotype were determined in 40 patients homozygous for hemoglobin SS and compared with 197 healthy children. Eleven of 40 patients with SCD had a history of stroke. The prevalence of homozygosity for the C677T MTHFR variant was 5% in the patients with SCD. The median Hcy level was 5.8 micromol/L in the patients versus 5.4 micromol/L in the controls (Fisher's, P > 0.05). There was no correlation of Hcy levels with the MTHFR genotype in patients with SCD. In patients with SCD and stroke, the median Hcy level was 4.8 micromol/L versus 6.0 micromol/L in those without stroke (P = 0.44, Mann-Whitney rank sum test). There was no difference in the proportion of patients with SCD with or without stroke who were homozygous for the C677T MTHFR mutation (0/11 versus 2/29; Fisher's, P = 1.000). In conclusion, this study failed to demonstrate an elevation in plasma Hcy levels in children with SCD compared with normal controls. Furthermore, hyperhomocysteinemia did not seem to be a significant factor in the pathogenesis of stroke in children with SCD. PMID:10524453

  18. The MTHFR C677T polymorphism contributes to increased risk of Alzheimer's disease: evidence based on 40 case-control studies.

    PubMed

    Peng, Qiliu; Lao, Xianjun; Huang, Xiuli; Qin, Xue; Li, Shan; Zeng, Zhiyu

    2015-01-23

    The association between methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and Alzheimer's Disease (AD) risk has been widely reported with inconsistent results. We performed an updated meta-analysis of all available studies to clarify this situation. We conducted a comprehensive literature search in PubMed Alzgene, Embase, and Chinese Biomedical Literature database (CBM) for the period up to June 2014. Finally, a total of 40 case-control studies with 4503 AD cases and 5767 controls were included. Overall, significant increased AD risk was found, when all studies were pooled into the meta-analysis. In subgroup analyses stratified by ethnicity, age of onset, and APOE ?4 status, significant increased AD risk was found in Asians, late-onset AD, and APOE ?4 carriers, but not in Caucasians, early-onset AD, and non-APOE ?4 carriers. The present meta-analysis suggested that the MTHFR is a candidate gene for AD susceptibility. The MTHFR C677T polymorphism may be a risk factor for AD in Asians, APOE ?4 carriers, and late-onset AD. Further, investigations taking the potential gene-gene and gene-environmental interactions into consideration for the MTHFR C677T polymorphism should be conducted. PMID:25486592

  19. Prevalence of MTHFR C677T and MS A2756G polymorphisms in major depressive disorder, and their impact on response to fluoxetine treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To examine the prevalence of the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and the A2756G polymorphism of methionine synthase (MS), and their impact on antidepressant response. We screened 224 subjects (52% female, mean age 39 +/- 11 years) with SCID-diagnosed major...

  20. MTHFR-Ala222Val and male infertility: a study in Iranian men, an updated meta-analysis and an in silico-analysis.

    PubMed

    Nikzad, Hossein; Karimian, Mohammad; Sareban, Kobra; Khoshsokhan, Maryam; Hosseinzadeh Colagar, Abasalt

    2015-11-01

    Methylenetetrahydrofolate reductase (MTHFR) functions as a main regulatory enzyme in folate metabolism. The association of MTHFR gene Ala222Val polymorphism with male infertility in an Iranian population was investigated by undertaking a meta-analysis and in-silico approach. A genetic association study included 497 men; 242 had unexplained infertility and 255 were healthy controls. Polymerase chain reaction restriction fragment length polymorphism was used for genotyping MTHFR-Ala222Val. OpenMeta[Analyst] software was used to conduct the analysis; 22 studies were identified by searching PubMed and the currently reported genetic association study. A novel in-silico approach was used to analyse the effects of Ala222Val substitution on the structure of mRNA and protein. Genetic association study revealed a significant association of MTHFR-222Val/Val genotype with oligozoospermia (OR 2.32; 95% CI, 1.12 to 4.78; P = 0.0451) and azoospermia (OR 2.59; 95% CI 1.09 to 6.17; P = 0.0314). Meta-analysis for allelic, dominant and codominant models showed a significant association between Ala222Val polymorphism and the risk of male infertility (P < 0.001). In silico-analysis showed MTHFR-Ala222Val affects enzyme structure and could also change the mRNA properties (P = 0.1641; P < 0.2 is significant). The meta-analysis suggested significant association of MTHFR-Ala222Val with risk of male infertility, especially in Asian populations. PMID:26380869

  1. The effect of 677C>T and 1298A>C MTHFR polymorphisms on sulfasalazine treatment outcome in rheumatoid arthritis.

    PubMed

    Pawlik, A; Kurzawski, M; Gawronska-Szklarz, B; Gornik, W; Dziedziejko, V; Safranow, K; Juzyszyn, Z; Drozdzik, M

    2009-07-01

    Despite the availability of several new agents for the treatment of rheumatoid arthritis (RA), sulfasalazine remains the mainstay because of both cost and experience with its use. Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and several polymorphisms have been described in the MTHFR gene. Of these, the 677C>T and 1298A>C polymorphisms have been associated with altered enzyme activity. To examine the association between 677C>T and 1298A>C MTHFR polymorphisms and sulfasalazine efficacy for the treatment of RA, a total of 117 RA patients treated with sulfasalazine (1 g daily; duration of treatment 17 +/- 5 months) were analyzed. The 677C>T and 1298 A>C polymorphisms were detected using a PCR-RFLP method. RA was diagnosed according to the criteria of the American College of Rheumatology (ACR). The remission of RA symptoms was evaluated according to the ACR 20% response criteria. Allele and genotype frequencies were compared by the two-sided Fisher exact test. The frequency of remission was 47.2% and 44.6% in carriers of 677T and 1298C alleles, compared to 40.7% and 42.0% in carriers of 677C and 1298A alleles, respectively. These differences were statistically non-significant. When the multivariate analysis was additionally adjusted for patients' age, gender and RA duration, the association of the MTHFR 677T allele with increased frequency of remission was statistically significant. Although RA remission rate in carriers of the MTHFR 677T and 1298C alleles was more frequently observed, it does not seem that 677C>T and 1298A>C MTHFR polymorphisms have a major influence on treatment outcome in RA patients treated with sulfasalazine. PMID:19578646

  2. Cerebral sinovenous thrombosis associated with MTHFR A1298C mutation in the newborn: a case report.

    PubMed

    Cizmeci, Mehmet Nevzat; Kanburoglu, Mehmet Kenan; Akelma, Ahmet Zulfikar; Donmez, Ahsen; Sonmez, Fatma Mujgan; Polat, Aziz; Kosehan, Dilek; Tatli, Mustafa Mansur

    2013-02-01

    Although cerebral sinovenous thrombosis (CSVT) is a rare condition in the neonatal period, high rates of morbidity and mortality necessitate the establishment of an early diagnosis. Methylenetetrahydrofolate reductase (MTHFR) plays a central role in the folate cycle and mutations of MTHFR are associated with vascular disease. While the C677T common missense mutation is the most well-defined MTHFR polymorphism, another common missense mutation, A1298C also exists. There has been no reported case of CSVT associated with MTHFR A1298C mutation in the neonatal period. Herein, we report a neonate with CSVT who was found to have MTHFR A1298C homozygosity. PMID:22797907

  3. NOD2 prevents emergence of disease-predisposing microbiota

    PubMed Central

    Secher, Thomas; Normand, Sylvain; Chamaillard, Mathias

    2013-01-01

    The gut flora is composed of a huge number of diverse, well-adapted symbionts that interact with epithelial lining throughout the host's entire life. Not all commensals have the same ability to maintain quiescent, protective inflammation. Importantly, instability in the composition of gut microbial communities (referred to as dysbiosis) has been linked to loss of gut barrier in the context of common human illnesses with increasing socio-economic impacts, such as Crohn disease and colorectal cancer. Our recent findings suggest that disease-predisposing dysbiosis can now be intentionally manipulated by targeting the major Crohn disease-predisposing NOD2 gene. That knowledge will not only add a new dimension to the often overlooked microbiology of Crohn disease and colorectal cancer, but will also have a broad impact on biomedical sciences worldwide. PMID:23778641

  4. MTHFR C677T polymorphism contributes to prostate cancer risk among Caucasians: A meta-analysis of 3511 cases and 2762 controls.

    PubMed

    Bai, Jian-Ling; Zheng, Ming-Hua; Xia, Xian; Ter-Minassian, Monica; Chen, Yong-Ping; Chen, Feng

    2009-05-01

    Published data regarding the association between 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphisms and prostate cancer risk have been conflicting. To derive a more precise estimation of the relationship, a meta-analysis was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between MTHFR C677T and A1298C polymorphisms and prostate cancer risk. Six studies including 3511 cases and 2762 controls described C677T genotypes, among which four articles totalling 838 cases and 1121 controls described A1298C genotypes, were involved in this meta-analysis. Overall meta-analysis indicated that the 677T allele was more likely to exert a protective effect on prostate cancer risk (OR=0.81, 95% CI: 0.68-0.98) with a recessive genetic model. No association was found for the 677CT genotype and the 677TT mutant homozygote with prostate cancer risk compared with 677CC, with OR=1.13 (95% CI: 0.88-1.45) and OR=0.85 (95% CI: 0.71-1.03), respectively. No evidence of an association of MTHFR A1298C polymorphism with prostate cancer was found. This meta-analysis supports that the C677T of the MTHFR gene is a low-penetrance susceptibility gene for prostate cancer, and might provide protective effects against prostate cancer risk. PMID:19223177

  5. MTHFR and MTRR genotype and haplotype analysis and colorectal cancer susceptibility in a case-control study from the Czech Republic.

    PubMed

    Pardini, Barbara; Kumar, Rajiv; Naccarati, Alessio; Prasad, Rashmi B; Forsti, Asta; Polakova, Veronika; Vodickova, Ludmila; Novotny, Jan; Hemminki, Kari; Vodicka, Pavel

    2011-03-18

    Polymorphic variants in genes involved in one-carbon metabolism, in particular of dietary folate, may modulate the risk for colorectal cancer through aberrant DNA-methylation and altered nucleotide synthesis and repair. In the present study, we have assessed the association of six polymorphisms and relative haplotypes in the MTHFR gene (rs1801133 and rs1801131) and in the MTRR gene (rs1801394, rs1532268, rs162036, and rs10380) with the risk for colorectal cancer in 666 patients and 1377 controls from the Czech Republic. We found that the 677 C>T polymorphism in the MTHFR gene significantly decreased the risk for colorectal cancer in homozygous carriers of the variant allele (OR, 0.58; 95% CI, 0.39-0.87). Also, we noted a significantly different distribution of genotypes between cases and controls for the 66A>G polymorphism in the MTRR gene. In particular, homozygous carriers of the G-containing allele of this polymorphism were at an increased risk for colorectal cancer (OR, 1.39; 95% CI, 1.04-1.85). Haplotype analysis of the two MTHFR polymorphisms showed a moderate difference in the distribution of the TA haplotype between cases and controls. In comparison to the most common haplotype (CA), the TA haplotype was associated with a decreased risk for colorectal cancer (OR, 0.84; 95% CI, 0.71-0.99). No difference in the distribution between cases and controls was observed for the haplotypes based on the four polymorphisms in the MTRR gene. The present study suggests that the 677TT genotype and the TA haplotype in the MTHFR gene may also have a role in colorectal cancer risk in the Czech population, indicating the importance of genes involved in folate metabolism with respect to cancer risk. For MTRR, additional studies on larger populations are needed to clarify the possible role of variation in this gene in colorectal carcinogenesis. PMID:21211571

  6. Maternal MTHFR variant forms increase the risk in offspring of isolated nonsyndromic cleft lip with or without cleft palate.

    PubMed

    Pezzetti, F; Martinelli, M; Scapoli, L; Carinci, F; Palmieri, A; Marchesini, J; Carinci, P; Caramelli, E; Rullo, R; Gombos, F; Tognon, M

    2004-07-01

    The pathogenesis of cleft lip with or without cleft palate (CL/P) is complex; its onset could be due to the interaction of various genetic and environmental factors. Recently MTHFR functional polymorphisms were found to increase the risk of this common malformation; however, this finding is still debated. We investigated 110 sporadic CL/P patients, their parents and 289 unrelated controls for c.665C>T (commonly known as 677C>T; p.Ala222Val) and c.1286A>C (known as 1298A>C; p.Glu429Ala) polymorphism in the MTHFR gene. Transmission disequilibrium test (TDT) showed no distortion in allele transmission. Nevertheless, association studies revealed significant differences in allele frequencies between mothers of CL/P patients and controls. This work supports the hypothesis that a lower MTHFR enzyme activity in pregnant women, mostly related to the c.665C>T variant form, is responsible for a higher risk of having CL/P affected offspring. PMID:15221800

  7. Polymorphisms of MTHFR Associated with Higher Relapse/Death Ratio and Delayed Weekly MTX Administration in Pediatric Lymphoid Malignancies

    PubMed Central

    Fukushima, Takashi; Sakai, Aiko; Suzuki, Ryoko; Nakajima-Yamaguchi, Ryoko; Kobayashi, Chie; Iwabuchi, Atsushi; Saito, Makoto; Yoshimi, Ai; Nakao, Tomohei; Kato, Keisuke; Tsuchida, Masahiro; Takahashi, Hideto; Koike, Kazutoshi; Kiyokawa, Nobutaka; Noguchi, Emiko; Sumazaki, Ryo

    2013-01-01

    Backgrounds. Outcome of childhood malignancy has been improved mostly due to the advances in diagnostic techniques and treatment strategies. While methotrexate (MTX) related polymorphisms have been under investigation in childhood malignancies, many controversial results have been offered. Objectives. To evaluate associations of polymorphisms related MTX metabolisms and clinical course in childhood lymphoid malignancies. Method. Eighty-two acute lymphoblastic leukemia and 21 non-Hodgkin's lymphoma children were enrolled in this study. Four single nucleotide polymorphisms in 2 genes (MTHFR (rs1801133/c.677C>T/p.Ala222Val and rs1801131/c.1298A>C/p.Glu429Ala) and SLCO1B1 (rs4149056/c.521T>C/p.V174A and rs11045879/c.1865+4846T>C)) were genotyped by Taqman PCR method or direct sequencing. Clinical courses were reviewed retrospectively. Results. No patient who had the AC/CC genotype of rs1801131 (MTHFR) had relapsed or died, in which distribution was statistically different among the AA genotype of rs1801131 (P = 0.004). Polymorphisms of SLCO1B1 (rs11045879 and rs4149056) were not correlated with MTX concentrations, adverse events, or disease outcome. Conclusions. Polymorphisms of MTHFR (rs1801131) could be the plausive candidate for prognostic predictor in childhood lymphoid malignancies. PMID:24386571

  8. Significant association between the MTHFR A1298C polymorphism and hepatocellular carcinoma risk: a meta-analysis.

    PubMed

    Chang, W; Meng, Q; Liu, J H; Wu, L X; Chen, Y; Chen, S D

    2015-01-01

    The A1298C polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene has been reported to be associated with hepatocellular carcinoma (HCC), but there are conflicting results from previous studies. The present study aimed to investigate the association between this polymorphism and the risk of HCC using a meta-analysis of the published studies. Published literature from PubMed and Embase databases was systematically searched to identify relevant studies before October 2014. The Begg test was used to measure publication bias. Sensitivity analyses were performed to ensure the authenticity of the outcome. The meta-analysis results showed significant association between the MTHFR A1298C polymorphism and HCC risk (CC vs AA: OR = 0.52, 95%CI = 0.33-0.81; CC vs AC: OR = 0.50, 95%CI = 0.32-0.79; dominant model: OR = 1.94, 95%CI = 1.24-3.02; recessive model: OR = 1.00, 95%CI = 0.84-1.18). In the subgroup analysis, significant associations between the MTHFR A1298C polymorphism and HCC risk were found in Asians (CC vs AA: OR = 0.46, 95%CI = 0.27-0.78; CC vs AC: OR = 0.41, 95%CI = 0.24-0.71; dominant model: OR = 2.27, 95%CI = 1.33-3.86; recessive model: OR = 1.03, 95%CI = 0.86-1.24). Our results suggest that the MTHFR A1298C polymorphism might be related to increased risk of HCC in Asians. Further large and well-designed studies are needed to confirm these conclusions. PMID:26662389

  9. A common variant in MTHFR influences response to chemoradiotherapy and recurrence of rectal cancer

    PubMed Central

    Nikas, Jason B; Lee, Janet T; Maring, Elizabeth D; Washechek-Aletto, Jill; Felmlee-Devine, Donna; Johnson, Ruth A; Smyrk, Thomas C; Tawadros, Patrick S; Boardman, Lisa A; Steer, Clifford J

    2015-01-01

    An important determinant of the pathogenesis and prognosis of various diseases is inherited genetic variation. Single-nucleotide polymorphisms (SNPs), variations at a single base position, have been identified in both protein-coding and noncoding DNA sequences, but the vast majority of millions of those variants are far from being functionally understood. Here we show that a common variant in the gene MTHFR [rs1801133 (C>T)] not only influences response to neoadjuvant chemoradiotherapy in patients with rectal cancer, but it also influences recurrence of the disease itself. More specifically, patients with the homozygous ancestral (wild type) genotype (C/C) were 2.91 times more likely (291% increased benefit) to respond to neoadjuvant chemoradiotherapy {95% CI: [1.23, 6.89]; P=0.0150} and 3.25 times more likely (325% increased benefit) not to experience recurrence of the disease {95% CI: [1.37, 7.72]; P=0.0079} than patients with either the heterozygous (C/T) or the homozygous mutation (T/T) genotype. These results identify MTHFR as an important genetic marker and open up new, pharmacogenomic strategies in the treatment and management of rectal cancer. PMID:26693073

  10. Association of methylenetetrahytrofolate reductase (MTHFR) C677T and A1298C polymorphisms with the susceptibility of childhood acute lymphoblastic leukaemia (ALL) in Chinese population

    PubMed Central

    2014-01-01

    Background The aim of this study was to investigate the relationship between the polymorphisms of the methylenetetrahytrofolate reductase (MTHFR) gene and susceptibility to childhood acute lymphoblastic leukemia (ALL). Methods A case–control study was conducted among 98 children with ALL and 93 age- and sex- matched non-ALL controls. Genotyping of MTHFR C677T and A1298C polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The odds ratios (ORs) of MTHFR genotypes were used to assess the associations of these polymorphisms with childhood ALL susceptibility. Results No significant differences were observed for frequencies of the 677CC, 677CT and 677TT genotypes between patients and controls. Frequencies of the 1298AA, 1298 AC and 1298CC genotypes between the two groups were significantly different. The risk of ALL with the 1298C allele carriers (AC?+?CC) was elevated by 1.1 times compared with the AA genotype [OR?=?2.100; 95% CI (1.149; 3.837); P?=?0.015]. Conclusions The MTHFR A1298C polymorphism is associated with susceptibility to childhood ALL in the Chinese population. PMID:24476575

  11. Association between MTHFR polymorphisms and congenital heart disease: a meta-analysis based on 9,329 cases and 15,076 controls.

    PubMed

    Xuan, Chao; Li, Hui; Zhao, Jin-Xia; Wang, Hong-Wei; Wang, Yi; Ning, Chun-Ping; Liu, Zhen; Zhang, Bei-Bei; He, Guo-Wei; Lun, Li-Min

    2014-01-01

    The aim of our study was to evaluate the association between polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and the risk for congenital heart disease (CHD). Electronic literature databases were searched to identify eligible studies published before Jun, 2014. The association was assessed by the odds ratio (OR) with a 95% confidence interval (CI). The publication bias was explored using Begg's test. Sensitivity analysis was performed to evaluate the stability of the crude results. A total of 35 studies were included in this meta-analysis. For the MTHFR C677T polymorphism, we detected significant association in all genetic models for Asian children and the maternal population. Significant association was also detected in T vs. C for a Caucasian paediatric population (OR = 1.163, 95% CI: 1.008-1.342) and in both T vs. C (OR = 1.125, 95% CI: 1.043-1.214) and the dominant model (OR = 1.216, 95% CI:b1.096-1.348) for a Caucasian maternal population. For the MTHFR A1298C polymorphism, the association was detected in CC vs. AC for the Caucasian paediatric population (OR = 1.484, 95% CI: 1.035-2.128). Our results support the MTHFR -677T allele as a susceptibility factor for CHD in the Asian maternal population and the -1298 C allele as a risk factor in the Caucasian paediatric population. PMID:25472587

  12. In human alleles specific variation of MTHFR C677T and A1298C associated "risk factor" for the development of ovarian cancer.

    PubMed

    Singh, Anupama; Pandey, S; Pandey, L K; Saxena, Ajit K

    2015-01-01

    Etiopathology of tumor biology is highly complex and ovarian cancer is one of the important gynaecological neoplasia associated with high risk of mortality rate. Methlenetetrahydrofolate reductase (MTHFR) mutation are commonly linked to folate metabolism with increased risk factor for the development of neural tube defects, recurrent pregnancy loss and development of several type of cancer but genetic interaction between two alleles of MTHFR has been poorly defined in ovarian cancer in India. Hence, present study becomes imperative with the aim to assess the alleles frequency of MTHFR (C677T & A1298C) gene polymorphism using PCR based RFLP analysis. The O.R at 95% confidence interval (C.I.) was computed between cases and their respective controls to determine "risk factor". Interestingly, our findings reveals highly significant (p < 0.001) difference in heterozygous (CT) condition of C677T allele by computing odd ratio (0.12 at 95% C.I, 0.021-0.0428; P for trend = 0.001) in controls and (0.34 at 95% C.I, 0.074-1.530; P for trend = 0.198) cases, suggesting that three time increase the "risk factor" for genetic susceptibility of MTHFR "T" allele for the development of ovarian carcinoma. PMID:26259392

  13. Association Between MTHFR Polymorphisms and Congenital Heart Disease: A Meta-analysis based on 9,329 cases and 15,076 controls

    PubMed Central

    Xuan, Chao; Li, Hui; Zhao, Jin-Xia; Wang, Hong-Wei; Wang, Yi; Ning, Chun-Ping; Liu, Zhen; Zhang, Bei-Bei; He, Guo-Wei; Lun, Li-Min

    2014-01-01

    The aim of our study was to evaluate the association between polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and the risk for congenital heart disease (CHD). Electronic literature databases were searched to identify eligible studies published before Jun, 2014. The association was assessed by the odds ratio (OR) with a 95% confidence interval (CI). The publication bias was explored using Begg's test. Sensitivity analysis was performed to evaluate the stability of the crude results. A total of 35 studies were included in this meta-analysis. For the MTHFR C677T polymorphism, we detected significant association in all genetic models for Asian children and the maternal population. Significant association was also detected in T vs. C for a Caucasian paediatric population (OR = 1.163, 95% CI: 1.008–1.342) and in both T vs. C (OR = 1.125, 95% CI: 1.043–1.214) and the dominant model (OR = 1.216, 95% CI:b1.096–1.348) for a Caucasian maternal population. For the MTHFR A1298C polymorphism, the association was detected in CC vs. AC for the Caucasian paediatric population (OR = 1.484, 95% CI: 1.035–2.128). Our results support the MTHFR -677T allele as a susceptibility factor for CHD in the Asian maternal population and the -1298C allele as a risk factor in the Caucasian paediatric population. PMID:25472587

  14. Histone modifications predispose genome regions to breakage and translocation

    PubMed Central

    Burman, Bharat; Zhang, Zhuzhu Z.; Pegoraro, Gianluca; Lieb, Jason D.; Misteli, Tom

    2015-01-01

    Chromosome translocations are well-established hallmarks of cancer cells and often occur at nonrandom sites in the genome. The molecular features that define recurrent chromosome breakpoints are largely unknown. Using a combination of bioinformatics, biochemical analysis, and cell-based assays, we identify here specific histone modifications as facilitators of chromosome breakage and translocations. We show enrichment of several histone modifications over clinically relevant translocation-prone genome regions. Experimental modulation of histone marks sensitizes genome regions to breakage by endonuclease challenge or irradiation and promotes formation of chromosome translocations of endogenous gene loci. Our results demonstrate that histone modifications predispose genome regions to chromosome breakage and translocations. PMID:26104467

  15. 32 CFR 644.391 - Predisposal conference.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the predisposal conference should provide for: (1) Determinations on maintenance guidelines based on... advisability of transferring custody and maintenance responsibilities to GSA at an early date. (4) Planning for... GSA. (b) It is of utmost importance that excess installations be put to productive use as...

  16. Sodium arsenite alters cell cycle and MTHFR, MT1/2, and c-Myc protein levels in MCF-7 cells

    SciTech Connect

    Ruiz-Ramos, Ruben; Lopez-Carrillo, Lizbeth; Albores, Arnulfo; Hernandez-Ramirez, Raul U.; Cebrian, Mariano E.

    2009-12-15

    There is limited available information on the effects of arsenic on enzymes participating in the folate cycle. Therefore, our aim was to evaluate the effects of sodium arsenite on the protein levels of methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase (DHFR) and its further relationship with the expression MT1/2 and c-myc in MCF-7 cells. Arsenite treatment (0-10 muM) for 4 h decreased MTHFR levels in a concentration-dependent fashion without significant effects on DHFR. The effects on MTHFR were observed at arsenite concentrations not significantly affecting cell viability. We also observed an increase in S-phase recruitment at all concentrations probed. Lower concentrations (< 5 muM) induced cell proliferation, showing a high proportion of BrdU-stained cells, indicating a higher DNA synthesis rate. However, higher concentrations (>= 5 muM) or longer treatment periods induced apoptosis. Arsenite also induced dose-dependent increases in MT1/2 and c-Myc protein levels. The levels of MTHFR were inversely correlated to MT1/2 and c-Myc overexpression and increased S-phase recruitment. Our findings indicate that breast epithelial cells are responsive to arsenite and suggest that exposure may pose a risk for breast cancer. The reductions in MTHFR protein levels contribute to understand the mechanisms underlying the induction of genes influencing growth regulation, such as c-myc and MT1/2. However, further research is needed to ascertain if the effects here reported following short-time and high-dose exposure are relevant for human populations chronically exposed to low arsenic concentrations.

  17. Low Birthweight (LBW) and Neonatal Hyperbilirubinemia (NNH) in an Indian Cohort: Association of Homocysteine, Its Metabolic Pathway Genes and Micronutrients as Risk Factors

    PubMed Central

    Sukla, Krishna Kishore; Tiwari, Pankaj Kumar; Kumar, Ashok; Raman, Rajiva

    2013-01-01

    Background & Aims Indian subcontinent has the highest child mortality rates along with a very high frequency of low birthweight (LBW). Folate and vitamin B12 (Vit-B12) are necessary during foetal development and their deficiency prevalence in Indians is very high. The objective of the present paper is to assess whether foetal homocysteine (Hcy)/folate metabolic pathway genes, their cofactors and homocysteine level independently (or collectively) predispose children to Low birth weight. Methods Cord blood was collected for the study. Frequency of 5 SNPs in 4-Hcy-pathway genes, and levels of Hcy, Vit-B12 and folate were evaluated. Results Of the 421 newborns recruited for the study, 38% showed low birth weight (<2.5kg) and 16% were preterm babies. 101 neonates developed neonatal hyperbilirubinemia (NNH). High prevalence of Vit-B12 (65%) and folate (27%) deficiency was observed in newborns along with hyperhomocystinemia (hypHcy-25%). Preterm delivery, micronutrient deficiency, hypHcy and MTHFR 677T SNP are associated as risk factor while G allele of TCN2 C776G is protective against LBW. MTHFR 677T allele and folate deficiency are also independent risk factors for NNH. Conclusion We record the highest incidence of Vit-B12, folate deficiency and elevated Hcy levels, of all the studies so far reported on neonates. These together with MTHFR 677T are potential risk factors for LBW. Association of impaired folate/Hcy metabolism with NNH is reported for the first time and the possible way of interaction is discussed. It appears that proper nutritional management during pregnancy would reduce the risk of complex clinical outcomes. PMID:23936521

  18. Predisposing factors and prevention of frostbite.

    PubMed

    Rintamäki, H

    2000-04-01

    This review focuses on the physiological, behavioural and environmental factors which predispose to frostbite. Also prevention of frostbite is summarised. Predisposing factors may increase heat loss, decrease heat production, decrease the insulation of the clothing, make people especially susceptible to cold or make them to behave inadequately. Marked increase in convective or conductive heat loss is often the immediate reason for frostbite. Wind (as described by wind chill index) increases convective heat loss and touching of metal objects increases conductive cooling. Poor insulation of the clothing is also a common reason of frostbite. The insulation can be insufficient when clothing is wet, tight, permeable to wind or does not cover the cold sensitive body parts. Individual factors predisposing to frostbite are inadequate behaviour, low physical fitness, fatigue, dehydration, earlier cold injuries, sickness or poor circulation in peripheral parts of the body. Frostbite is often associated with the use of alcohol. To prevent frostbite, it is necessary to recognise cold risks, practise tasks in the cold, eat and drink well, have physical exercise, have sufficient clothing (also spare clothing), change into dry clothing if necessary and take care of companions. In the cold it is not advisable to get fatigued until exhaustion, sweat excessively, use tight and/or wet clothing, drink alcohol, smoke and expose oneself unnecessarily to wind, metals or fluids. PMID:10998828

  19. Macrolide antibiotics allosterically predispose the ribosome for translation arrest.

    PubMed

    Sothiselvam, Shanmugapriya; Liu, Bo; Han, Wei; Ramu, Haripriya; Klepacki, Dorota; Atkinson, Gemma Catherine; Brauer, Age; Remm, Maido; Tenson, Tanel; Schulten, Klaus; Vázquez-Laslop, Nora; Mankin, Alexander S

    2014-07-01

    Translation arrest directed by nascent peptides and small cofactors controls expression of important bacterial and eukaryotic genes, including antibiotic resistance genes, activated by binding of macrolide drugs to the ribosome. Previous studies suggested that specific interactions between the nascent peptide and the antibiotic in the ribosomal exit tunnel play a central role in triggering ribosome stalling. However, here we show that macrolides arrest translation of the truncated ErmDL regulatory peptide when the nascent chain is only three amino acids and therefore is too short to be juxtaposed with the antibiotic. Biochemical probing and molecular dynamics simulations of erythromycin-bound ribosomes showed that the antibiotic in the tunnel allosterically alters the properties of the catalytic center, thereby predisposing the ribosome for halting translation of specific sequences. Our findings offer a new view on the role of small cofactors in the mechanism of translation arrest and reveal an allosteric link between the tunnel and the catalytic center of the ribosome. PMID:24961372

  20. Macrolide antibiotics allosterically predispose the ribosome for translation arrest

    PubMed Central

    Sothiselvam, Shanmugapriya; Liu, Bo; Han, Wei; Ramu, Haripriya; Klepacki, Dorota; Atkinson, Gemma Catherine; Brauer, Age; Remm, Maido; Tenson, Tanel; Schulten, Klaus; Vázquez-Laslop, Nora; Mankin, Alexander S.

    2014-01-01

    Translation arrest directed by nascent peptides and small cofactors controls expression of important bacterial and eukaryotic genes, including antibiotic resistance genes, activated by binding of macrolide drugs to the ribosome. Previous studies suggested that specific interactions between the nascent peptide and the antibiotic in the ribosomal exit tunnel play a central role in triggering ribosome stalling. However, here we show that macrolides arrest translation of the truncated ErmDL regulatory peptide when the nascent chain is only three amino acids and therefore is too short to be juxtaposed with the antibiotic. Biochemical probing and molecular dynamics simulations of erythromycin-bound ribosomes showed that the antibiotic in the tunnel allosterically alters the properties of the catalytic center, thereby predisposing the ribosome for halting translation of specific sequences. Our findings offer a new view on the role of small cofactors in the mechanism of translation arrest and reveal an allosteric link between the tunnel and the catalytic center of the ribosome. PMID:24961372

  1. MAT2A mutations predispose individuals to thoracic aortic aneurysms.

    PubMed

    Guo, Dong-chuan; Gong, Limin; Regalado, Ellen S; Santos-Cortez, Regie L; Zhao, Ren; Cai, Bo; Veeraraghavan, Sudha; Prakash, Siddharth K; Johnson, Ralph J; Muilenburg, Ann; Willing, Marcia; Jondeau, Guillaume; Boileau, Catherine; Pannu, Hariyadarshi; Moran, Rocio; Debacker, Julie; Bamshad, Michael J; Shendure, Jay; Nickerson, Deborah A; Leal, Suzanne M; Raman, C S; Swindell, Eric C; Milewicz, Dianna M

    2015-01-01

    Up to 20% of individuals who have thoracic aortic aneurysms or acute aortic dissections but who do not have syndromic features have a family history of thoracic aortic disease. Significant genetic heterogeneity is established for this familial condition. Whole-genome linkage analysis and exome sequencing of distant relatives from a large family with autosomal-dominant inheritance of thoracic aortic aneurysms variably associated with the bicuspid aortic valve was used for identification of additional genes predisposing individuals to this condition. A rare variant, c.1031A>C (p.Glu344Ala), was identified in MAT2A, which encodes methionine adenosyltransferase II alpha (MAT II?). This variant segregated with disease in the family, and Sanger sequencing of DNA from affected probands from unrelated families with thoracic aortic disease identified another MAT2A rare variant, c.1067G>A (p.Arg356His). Evidence that these variants predispose individuals to thoracic aortic aneurysms and dissections includes the following: there is a paucity of rare variants in MAT2A in the population; amino acids Glu344 and Arg356 are conserved from humans to zebrafish; and substitutions of these amino acids in MAT I? are found in individuals with hypermethioninemia. Structural analysis suggested that p.Glu344Ala and p.Arg356His disrupt MAT II? enzyme function. Knockdown of mat2aa in zebrafish via morpholino oligomers disrupted cardiovascular development. Co-transfected wild-type human MAT2A mRNA rescued defects of zebrafish cardiovascular development at significantly higher levels than mRNA edited to express either the Glu344 or Arg356 mutants, providing further evidence that the p.Glu344Ala and p.Arg356His substitutions impair MAT II? function. The data presented here support the conclusion that rare genetic variants in MAT2A predispose individuals to thoracic aortic disease. PMID:25557781

  2. MTHFR 677C>T and ACE D/I Polymorphisms in Migraine: A Systematic Review and Meta-Analysis

    PubMed Central

    Schürks, Markus; Rist, Pamela M.; Kurth, Tobias

    2011-01-01

    Background Data on the association between the MTHFR 677C>T and ACE D/I polymorphisms and migraine including aura status are conflicting. Objective To perform a systematic review and meta-analysis on this topic. Methods We searched for studies published until March 2009 using electronic databases (MEDLINE, EMBASE, Science Citation Index) and reference lists of studies and reviews on the topic. Assessment for eligibility of studies and extraction of data was performed by two independent investigators. For each study we calculated the odds ratios (OR) and 95% confidence intervals (CI) assuming additive, dominant, and recessive genetic models. We then calculated pooled ORs and 95% CIs. Results Thirteen studies investigated the association between the MTHFR 677C>T polymorphism and migraine. The TT genotype was associated with an increased risk for any migraine, which only appeared for migraine with aura (pooled OR=1.48, 95% CI 1.02–2.13), but not migraine without aura. Nine studies investigated the association of the ACE D/I polymorphism with migraine. The II genotype was associated with a reduced risk for migraine with (pooled OR=0.71, 95% CI 0.55–0.93) and without aura (pooled OR=0.84, 95% CI 0.70–0.99). Results for both variants were driven by studies in non-Caucasian populations. Results among Caucasians did not suggest an association. Extractable data did not allow investigation of gene-gene-interactions. Conslusions The MTHFR 677TT genotype is associated with an increased risk for migraine with aura, while the ACE II genotype is protective against both migraine with and without aura. Results for both variants appeared only among non-Caucasian populations. There was no association among Caucasians. PMID:19925624

  3. MTHFR 677 C>T and 1298 A>C polymorphisms and the age of onset of colorectal cancer in hereditary nonpolyposis colorectal cancer.

    PubMed

    Reeves, Stuart G; Meldrum, Cliff; Groombridge, Claire; Spigelman, Allan D; Suchy, Janina; Kurzawski, Grzegorz; Lubinski, Jan; McElduff, Patrick; Scott, Rodney J

    2009-05-01

    Hereditary non-polyposis colorectal cancer (HNPCC) or Lynch syndrome is characterized by inactivating germline mutations in DNA mismatch repair genes resulting in an increased risk of developing an epithelial malignancy. There is considerable variability in disease expression observed in this syndrome, which is thought to be due to a combination of genetic and environmental factors. Alterations in the kinetics of methylene tetrahydrofolate reductase (MTHFR) due to the presence of polymorphisms in the MTHFR gene have been associated with an increased risk of colorectal cancer (CRC). Two common single nucleotide polymorphisms (SNPs) located within the MTHFR gene, 677 C>T and 1298 A>C, that alter the function of the encoded protein have been the focus of many studies on CRC risk outside the context of an inherited predisposition to disease. In this report, a total of 417 HNPCC participants were genotyped for the 677 C>T and 1298 A>C SNPs to determine whether there exists an association with the age of disease onset of CRC. Genotyping of both SNPs was performed by TaqMan(R) assay technology. Associations in disease risk were further investigated using Kaplan-Meier survival analysis and Cox hazard regression. The average ages of disease diagnosis were found to be different between individuals harbouring either one of the MTHFR polymorphisms. Both Kaplan-Meier and Cox hazard regression analyses revealed a more complex relationship between the two polymorphisms and the age of CRC onset. The Kaplan-Meier survival analysis revealed that compound heterozygotes for the two SNPs developed CRC 10 years later compared with those carrying only wild-type alleles. PMID:19156174

  4. Hyperhomocysteinemia and MTHFR polymorphisms as antenatal risk factors of white matter abnormalities in two cohorts of late preterm and full term newborns.

    PubMed

    Marseglia, Lucia M; Nicotera, Antonio; Salpietro, Vincenzo; Giaimo, Elisa; Cardile, Giovanna; Bonsignore, Maria; Alibrandi, Angela; Caccamo, Daniela; Manti, Sara; D'Angelo, Gabriella; Mamì, Carmelo; Di Rosa, Gabriella

    2015-01-01

    Higher total homocysteine (tHcy) levels, and C677T and A1298C methylenetetrahydrofolate (MTHFR) polymorphisms, have been reported in preterm or full term newborns with neonatal encephalopathy following perinatal hypoxic-ischemic insult. This study investigated the causal role of tHcy and MTHFR polymorphisms together with other acquired risk factors on the occurrence of brain white matter abnormalities (WMA) detected by cranial ultrasound scans (cUS) in a population of late preterm and full term infants. A total of 171 newborns (81?M, 47.4%), 45 (26.3%) born <37?wks, and 126 (73.7%) born ?37?wks were recruited in the study. cUS detected predominant WMA pattern in 36/171 newborns (21.1%) mainly characterized by abnormal periventricular white matter signal and mild-to-moderate periventricular white matter volume loss with ventricular dilatation (6/36, 16.6%). WMA resulted in being depending on tHcy levels (P < 0.014), lower GA (P < 0.000), lower Apgar score at 1 minutes (P < 0.000) and 5 minutes (P < 0.000), and 1298AC and 677CT/1298AC genotypes (P < 0.000 and P < 0.000). In conclusion, both acquired and genetic predisposing antenatal factors were significantly associated with adverse neonatal outcome and WMA. The role of A1298C polymorphism may be taken into account for prenatal assessment and treatment counseling. PMID:25829992

  5. Hyperhomocysteinemia and MTHFR Polymorphisms as Antenatal Risk Factors of White Matter Abnormalities in Two Cohorts of Late Preterm and Full Term Newborns

    PubMed Central

    Marseglia, Lucia M.; Nicotera, Antonio; Salpietro, Vincenzo; Giaimo, Elisa; Cardile, Giovanna; Bonsignore, Maria; Alibrandi, Angela; Caccamo, Daniela; Manti, Sara; D'Angelo, Gabriella; Mamì, Carmelo; Di Rosa, Gabriella

    2015-01-01

    Higher total homocysteine (tHcy) levels, and C677T and A1298C methylenetetrahydrofolate (MTHFR) polymorphisms, have been reported in preterm or full term newborns with neonatal encephalopathy following perinatal hypoxic-ischemic insult. This study investigated the causal role of tHcy and MTHFR polymorphisms together with other acquired risk factors on the occurrence of brain white matter abnormalities (WMA) detected by cranial ultrasound scans (cUS) in a population of late preterm and full term infants. A total of 171 newborns (81?M, 47.4%), 45 (26.3%) born <37?wks, and 126 (73.7%) born ?37?wks were recruited in the study. cUS detected predominant WMA pattern in 36/171 newborns (21.1%) mainly characterized by abnormal periventricular white matter signal and mild-to-moderate periventricular white matter volume loss with ventricular dilatation (6/36, 16.6%). WMA resulted in being depending on tHcy levels (P < 0.014), lower GA (P < 0.000), lower Apgar score at 1 minutes (P < 0.000) and 5 minutes (P < 0.000), and 1298AC and 677CT/1298AC genotypes (P < 0.000 and P < 0.000). In conclusion, both acquired and genetic predisposing antenatal factors were significantly associated with adverse neonatal outcome and WMA. The role of A1298C polymorphism may be taken into account for prenatal assessment and treatment counseling. PMID:25829992

  6. Increased resistance to malaria in mice with methylenetetrahydrofolate reductase (Mthfr) deficiency suggests a mechanism for selection of the MTHFR 677C>T (c.665C>T) variant.

    PubMed

    Meadows, Danielle N; Pyzik, Michal; Wu, Qing; Torre, Sabrina; Gros, Philippe; Vidal, Silvia M; Rozen, Rima

    2014-05-01

    The polymorphism 677C>T (NM_005957.4:c.665C>T/p.Ala222Val, rs1801133:C>T) in methylenetetrahydrofolate reductase (MTHFR) results in mild enzymatic deficiency and increased risk for several complex traits including adverse reproductive outcomes, birth defects, and heart disease. Despite these deleterious effects, homozygosity is high (5%-15%) in many populations, and among the highest in Mediterranean regions, where malaria was historically endemic and may have conferred a selective advantage for other mutations. We infected Mthfr-deficient (Mthfr(+) (/-) ) and MTHFR overexpressing (MTHFR(Tg) ) mice with Plasmodium berghei ANKA to induce cerebral malaria. Mthfr(+/-) mice survived longer (P < 0.02, log-rank test), and MTHFR(Tg) mice died earlier (P < 0.05, log-rank test) after infection compared with wild-type littermates. Flow cytometry revealed increased lymphocyte populations and increased CCR4(+) NK cells in spleen of Mthfr(+) (/-) mice; MTHFR(Tg) animals had decreased numbers of these NK cells. Interferon-? and interleukin-10 immunoreactive proteins were increased and decreased, respectively, in brain of Mthfr(+/-) mice compared with wild-type. We suggest that mild MTHFR deficiency protects against malarial infection and that this phenomenon may have led to the high frequency of the 677C>T/c.665C>T variant in human populations. PMID:24616178

  7. What aspects of autism predispose to talent?

    PubMed Central

    Happé, Francesca; Vital, Pedro

    2009-01-01

    In this paper, we explore the question, why are striking special skills so much more common in autism spectrum conditions (ASC) than in other groups? Current cognitive accounts of ASC are briefly reviewed in relation to special skills. Difficulties in ‘theory of mind’ may contribute to originality in ASC, since individuals who do not automatically ‘read other minds’ may be better able to think outside prevailing fashions and popular theories. However, originality alone does not confer talent. Executive dysfunction has been suggested as the ‘releasing’ mechanism for special skills in ASC, but other groups with executive difficulties do not show raised incidence of talents. Detail-focused processing bias (‘weak coherence’, ‘enhanced perceptual functioning’) appears to be the most promising predisposing characteristic, or ‘starting engine’, for talent development. In support of this notion, we summarize data from a population-based twin study in which parents reported on their 8-year-olds' talents and their ASC-like traits. Across the whole sample, ASC-like traits, and specifically ‘restricted and repetitive behaviours and interests’ related to detail focus, were more pronounced in children reported to have talents outstripping older children. We suggest that detail-focused cognitive style predisposes to talent in savant domains in, and beyond, autism spectrum disorders. PMID:19528019

  8. What aspects of autism predispose to talent?

    PubMed

    Happé, Francesca; Vital, Pedro

    2009-05-27

    In this paper, we explore the question, why are striking special skills so much more common in autism spectrum conditions (ASC) than in other groups? Current cognitive accounts of ASC are briefly reviewed in relation to special skills. Difficulties in 'theory of mind' may contribute to originality in ASC, since individuals who do not automatically 'read other minds' may be better able to think outside prevailing fashions and popular theories. However, originality alone does not confer talent. Executive dysfunction has been suggested as the 'releasing' mechanism for special skills in ASC, but other groups with executive difficulties do not show raised incidence of talents. Detail-focused processing bias ('weak coherence', 'enhanced perceptual functioning') appears to be the most promising predisposing characteristic, or 'starting engine', for talent development. In support of this notion, we summarize data from a population-based twin study in which parents reported on their 8-year-olds' talents and their ASC-like traits. Across the whole sample, ASC-like traits, and specifically 'restricted and repetitive behaviours and interests' related to detail focus, were more pronounced in children reported to have talents outstripping older children. We suggest that detail-focused cognitive style predisposes to talent in savant domains in, and beyond, autism spectrum disorders. PMID:19528019

  9. Cox4i2, Ifit2, and Prdm11 Mutant Mice: Effective Selection of Genes Predisposing to an Altered Airway Inflammatory Response from a Large Compendium of Mutant Mouse Lines.

    PubMed

    Horsch, Marion; Aguilar-Pimentel, Juan Antonio; Bönisch, Clemens; Côme, Christophe; Kolster-Fog, Cathrine; Jensen, Klaus T; Lund, Anders H; Lee, Icksoo; Grossman, Lawrence I; Sinkler, Christopher; Hüttemann, Maik; Bohn, Erwin; Fuchs, Helmut; Ollert, Markus; Gailus-Durner, Valérie; de Angelis, Martin Hrab?; Beckers, Johannes

    2015-01-01

    We established a selection strategy to identify new models for an altered airway inflammatory response from a large compendium of mutant mouse lines that were systemically phenotyped in the German Mouse Clinic (GMC). As selection criteria we included published gene functional data, as well as immunological and transcriptome data from GMC phenotyping screens under standard conditions. Applying these criteria we identified a few from several hundred mutant mouse lines and further characterized the Cox4i2tm1Hutt, Ifit2tm1.1Ebsb, and Prdm11tm1.1ahl lines following ovalbumin (OVA) sensitization and repeated OVA airway challenge. Challenged Prdm11tm1.1ahl mice exhibited changes in B cell counts, CD4+ T cell counts, and in the number of neutrophils in bronchoalveolar lavages, whereas challenged Ifit2tm1.1Ebsb mice displayed alterations in plasma IgE, IgG1, IgG3, and IgM levels compared to the challenged wild type littermates. In contrast, challenged Cox4i2tm1Hutt mutant mice did not show alterations in the humoral or cellular immune response compared to challenged wild type mice. Transcriptome analyses from lungs of the challenged mutant mouse lines showed extensive changes in gene expression in Prdm11tm1.1ahl mice. Functional annotations of regulated genes of all three mutant mouse lines were primarily related to inflammation and airway smooth muscle (ASM) remodeling. We were thus able to define an effective selection strategy to identify new candidate genes for the predisposition to an altered airway inflammatory response under OVA challenge conditions. Similar selection strategies may be used for the analysis of additional genotype-envirotype interactions for other diseases. PMID:26263558

  10. Cox4i2, Ifit2, and Prdm11 Mutant Mice: Effective Selection of Genes Predisposing to an Altered Airway Inflammatory Response from a Large Compendium of Mutant Mouse Lines

    PubMed Central

    Bönisch, Clemens; Côme, Christophe; Kolster-Fog, Cathrine; Jensen, Klaus T.; Lund, Anders H.; Lee, Icksoo; Grossman, Lawrence I.; Sinkler, Christopher; Hüttemann, Maik; Bohn, Erwin; Fuchs, Helmut; Ollert, Markus; Gailus-Durner, Valérie; Hrabĕ de Angelis, Martin; Beckers, Johannes

    2015-01-01

    We established a selection strategy to identify new models for an altered airway inflammatory response from a large compendium of mutant mouse lines that were systemically phenotyped in the German Mouse Clinic (GMC). As selection criteria we included published gene functional data, as well as immunological and transcriptome data from GMC phenotyping screens under standard conditions. Applying these criteria we identified a few from several hundred mutant mouse lines and further characterized the Cox4i2tm1Hutt, Ifit2tm1.1Ebsb, and Prdm11tm1.1ahl lines following ovalbumin (OVA) sensitization and repeated OVA airway challenge. Challenged Prdm11tm1.1ahl mice exhibited changes in B cell counts, CD4+ T cell counts, and in the number of neutrophils in bronchoalveolar lavages, whereas challenged Ifit2tm1.1Ebsb mice displayed alterations in plasma IgE, IgG1, IgG3, and IgM levels compared to the challenged wild type littermates. In contrast, challenged Cox4i2tm1Hutt mutant mice did not show alterations in the humoral or cellular immune response compared to challenged wild type mice. Transcriptome analyses from lungs of the challenged mutant mouse lines showed extensive changes in gene expression in Prdm11tm1.1ahl mice. Functional annotations of regulated genes of all three mutant mouse lines were primarily related to inflammation and airway smooth muscle (ASM) remodeling. We were thus able to define an effective selection strategy to identify new candidate genes for the predisposition to an altered airway inflammatory response under OVA challenge conditions. Similar selection strategies may be used for the analysis of additional genotype – envirotype interactions for other diseases. PMID:26263558

  11. Incidence Assessment of MTHFR C677T and A1298C Polymorphisms in Iranian Non-syndromic Cleft Lip and/or Palate Patients.

    PubMed

    Ebadifar, Asghar; Ameli, Nazila; Khorramkhorshid, Hamid Reza; Salehi Zeinabadi4, Mehdi; Kamali, Kourosh; Khoshbakht, Tayyebeh

    2015-01-01

    Background and aims. The aim of the present study is to determine the incidence of MTHFR C677 T and A1298C muta-tions in Iranian patients with cleft lip and/or cleft palate. Materials and methods. We screened 61 Iranian patients with cleft lip and/or cleft palate for mutations in the two alleles of MTHFR gene associated with cleft lip and/or palate: A1298C and C677T, using Polymerase Chain Reaction following by RFLP. Results. The 677T and 1298C homozygote genotypes showed a frequency of 36.1% and 11.4%, respectively. Combined genotype frequencies in newborns having oral clefts showed that the highest genotype was 677TT/1298AA (22.9%) and 677TT/1298CC genotypes were not observed. Conclusion. The results showed that 65.6% of all patients had at least one T mutant allele in C677T and 58.9% C mutant allele for A1298C. According to the frequencies of homozygosity of mutant alleles, it could be said that MTHFR genotype of 677TT shows a greater role in having oral clefts. PMID:26236436

  12. Incidence Assessment of MTHFR C677T and A1298C Polymorphisms in Iranian Non-syndromic Cleft Lip and/or Palate Patients

    PubMed Central

    Ebadifar, Asghar; Ameli, Nazila; Khorramkhorshid, Hamid Reza; Salehi Zeinabadi4, Mehdi; Kamali, Kourosh; Khoshbakht, Tayyebeh

    2015-01-01

    Background and aims. The aim of the present study is to determine the incidence of MTHFR C677 T and A1298C muta-tions in Iranian patients with cleft lip and/or cleft palate. Materials and methods. We screened 61 Iranian patients with cleft lip and/or cleft palate for mutations in the two alleles of MTHFR gene associated with cleft lip and/or palate: A1298C and C677T, using Polymerase Chain Reaction following by RFLP. Results. The 677T and 1298C homozygote genotypes showed a frequency of 36.1% and 11.4%, respectively. Combined genotype frequencies in newborns having oral clefts showed that the highest genotype was 677TT/1298AA (22.9%) and 677TT/1298CC genotypes were not observed. Conclusion. The results showed that 65.6% of all patients had at least one T mutant allele in C677T and 58.9% C mutant allele for A1298C. According to the frequencies of homozygosity of mutant alleles, it could be said that MTHFR genotype of 677TT shows a greater role in having oral clefts. PMID:26236436

  13. Association between 5, 10-methylenetetrahydrofolate reductase (MTHFR) polymorphisms and congenital heart disease: A meta-analysis?

    PubMed Central

    Wang, Wenju; Hou, Zongliu; Wang, Chunhui; Wei, Chuanyu; Li, Yaxiong; Jiang, Lihong

    2013-01-01

    Background Inconsistent results were reported in recent literature regarding the association between methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and the susceptibility of congenital heart disease (CHD). In this study, we performed a meta-analysis to investigate the associations by employing multiple analytical methods. Methods Literature search was performed and published articles were obtained from PubMed, Embase and CNKI databases based on the exclusion and inclusion criteria. Data were extracted from eligible studies and the crude odds ratios and their corresponding 95% confidence intervals (CIs) were calculated using random or fix effects model to evaluate the associations between the MTHFR C677T/A1298C polymorphisms and CHD development. Subgroup based analysis was performed by Hardy–Weinberg equilibrium, ethnicity, types of CHD, source of control and sample size. Results Twenty-four eligible studies were included in this meta-analysis. Significant association was found between fetal MTHFR C677T polymorphism and CHD development in all genetic models. The pooled ORs and 95% CIs in all genetic models indicated that MTHFR C677T polymorphism was significantly associated with CHD in Asian, but not Caucasian in subgroup analysis. The maternal MTHFR C677T polymorphism was not associated with CHD except for recessive model. Moreover, neither maternal nor fetal MTHFR A1298C polymorphism was associated with CHD. Conclusion The fetal MTHFR C677T polymorphism may increase the susceptibility to CHD. Fetal MTHFR C677T polymorphism was more likely to affect Asian fetus than Caucasian. The MTHFR A1298C polymorphism may not be a risk of congenital heart disease. PMID:25606381

  14. Is MTHFR 677 C>T Polymorphism Clinically Important in Polycystic Ovarian Syndrome (PCOS)? A Case-Control Study, Meta-Analysis and Trial Sequential Analysis

    PubMed Central

    Carlus, S. Justin; Sarkar, Saumya; Bansal, Sandeep Kumar; Singh, Vertika; Singh, Kiran; Jha, Rajesh Kumar; Sadasivam, Nirmala; Sadasivam, Sri Revathy; Gireesha, P. S.; Thangaraj, Kumarasamy; Rajender, Singh

    2016-01-01

    Background Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies. Methods and Results We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71–1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04–2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations. Conclusion In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium. PMID:26983014

  15. Association of single nucleotide polymorphisms in MTHFR and ABCG2 with the different efficacy of first-line chemotherapy in metastatic colorectal cancer.

    PubMed

    Zhao, Jing; Li, Wenhua; Zhu, Dan; Yu, Qihe; Zhang, Zhe; Sun, Menghong; Cai, Sanjun; Zhang, Wen

    2014-01-01

    Either oxaliplatin- or irinotecan-containing regimen could receive a good effectiveness in patients with metastatic colorectal cancer as the first-line chemotherapy, but not all patients would benefit from the treatment they have received. This study was to investigate the role of single nucleotide polymorphisms (SNPs) of methylenetetrahydrofolate reductase (MTHFR) and ATP-binding cassette sub-family G member 2 (ABCG2) in selecting the most appropriate treatment for individual patients. Ninety-two metastatic colorectal cancer patients treated with first-line 5-fluoropyrimidine (5-FU), leucovorin, and oxaliplatin (FOLFOX), capecitabine, and oxaliplatin (XELOX) and sixty-two patients receiving 5-FU, leucovorin, and irinotecan (FOLFIRI) were reviewed. The SNPs of MTHFR and ABCG2 were detected using gene sequencing method after DNA PCR amplification, which was extracted from peripheral blood karyocytes. Clinical characteristics and gene polymorphisms were evaluated in univariate and multivariate analysis as predictive factors for response rate (RR) and progression-free survival (PFS). In patients bearing 2-4 genotypes of MTHFR 677C/C, MTHFR 1298 A/C or C/C, ABCG2 34G/G, and ABCG2 421C/A or A/A, those who received oxaliplatin-based chemotherapy achieved a higher RR (41.7 vs. 18.8 %, P = 0.027) and longer median PFS (mPFS) than irinotecan-based therapy [8.9 vs. 7.1 m, FOLFIRI: hazard ratio (HR) = 1.722, 95 % confidence interval (CI) 1.026-2.892, P = 0.040, compared with FOLFOX/XELOX]; on the contrary, patients carrying 0 or 1 above genotype exhibited better outcomes after receiving FOLFIRI chemotherapy (mPFS: 9.3 vs. 6.4 m, FOLFIRI: HR = 0.422, 95 % CI 0.205-0.870, P = 0.019, compared with FOLFOX/XELOX). Combination of SNPs with MTHFR and ABCG2 may play a role in helping clinicians to select first-line chemotherapy for patients with metastatic colorectal cancer. PMID:24338217

  16. Sequence variation of the methylene tetrahydrofolate reductase gene (677C>T and 1298?A>C) and traditional risk factors in a South Indian population.

    PubMed

    Dayakar, Seetha; Goud, Kalal Iravathy; Reddy, Thavanati Parvathi Kumara; Rao, Seshagiri P; Sesikeran, Shyamala B; Sadhnani, Muralidhar

    2011-11-01

    Methylene tetrahydrofolate reductase (MTHFR) plays a significant role in the metabolism of methionine. MTHFR deficiency is an autosomal recessive trait that could be a significant risk factor for a number of defects, for example, vascular events, due to lower dietary folate intake among South Indians. To find the incidence of 677 C>T and 1298?A>C in MTHFR gene single nucleotide polymorphisms (SNPs) among the south Indian population, polymerase chain reaction and restriction fragment length polymorphism were employed among 152 patients with myocardial infarction and 167 controls. The MTHFR 677CT genotype was found among 35 (22.4%) cases and 08 (4.8%) controls, the MTHFR 677CC allele was found among 115 (73.7%) cases and 159 (94.6%) controls. Also, the analysis of the MTHFR 1298A>C SNP identified the MTHFR 1298CC genotype among 16 (10.3%) cases and 01 (0.6%) control, the MTHFR 1298AC genotype was found in 56 (35.9%) cases and 27 (16.2%) controls, and the MTHFR 1298AA genotype was observed in 80 (51.3%) cases and 139 (82.6%) controls. The C vs. A allele also showed significantly higher frequency among the patients in comparison with the controls (p<0.0001). The results of this study indicate that the MTHFR A1298C SNP is more prevalent among south Indians compared with the MTHFR C677T SNP, suggesting a possible role of MTHFR A1298C in the pathogenesis of heart diseases. PMID:21749215

  17. Runx1 deficiency predisposes mice to T-lymphoblastic lymphoma

    PubMed Central

    Kundu, Mondira; Compton, Sheila; Garrett-Beal, Lisa; Stacy, Terryl; Starost, Matthew F.; Eckhaus, Michael; Speck, Nancy A.; Liu, P. Paul

    2005-01-01

    Chromosomal rearrangements affecting RUNX1 and CBFB are common in acute leukemias. These mutations result in the expression of fusion proteins that act dominant-negatively to suppress the normal function of the Runt-related transcription factor 1 (RUNX)/core binding factor ? (CBF?) complexes. In addition, loss-of-function mutations in Runt-related transcription factor 1 (RUNX1) have been identified in sporadic cases of acute myeloid leukemia (AML) and in association with the familial platelet disorder with propensity to develop AML (FPD/AML). In order to examine the hypothesis that decreased gene dosage of RUNX1 may be a critical event in the development of leukemia, we treated chimeric mice generated from Runx1lacZ/lacZ embryonic stem (ES) cells that have homozygous disruption of the Runx1 gene with N-ethyl-N-nitrosourea (ENU). We observed an increased incidence of T-lymphoblastic lymphoma in Runx1lacZ/lacZ compared with wild-type chimeras and confirmed that the tumors were of ES-cell origin. Our results therefore suggest that deficiency of Runx1 can indeed predispose mice to hematopoietic malignancies. PMID:16051740

  18. Quantitative assessment of the association between MTHFR rs1801131 polymorphism and risk of liver cancer.

    PubMed

    Liang, Tie-Jun; Liu, Hui; Zhao, Xiao-Qian; Tan, Yan-Rong; Jing, Kai; Qin, Cheng-Yong

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is one of the most important enzymes for folate metabolism which plays a key role in cell metabolism. MTHFR rs1801131 (A1298C) polymorphism can decrease in vitro MTHFR enzyme activity and has been hypothesized to be associated with liver cancer risk. This study aimed to quantify the strength of the association between MTHFR rs1801131 polymorphism and liver cancer risk by performing a meta-analysis. We searched the PubMed and Wanfang databases for studies relating on the association between MTHFR rs1801131 polymorphism and risk of liver cancer. Seven studies with 2,030 cases of liver cancer and 3,096 controls were finally included into the meta-analysis. Meta-analysis of a total of seven studies showed that the homozygote genotype CC of MTHFR rs1801131 polymorphism was significantly associated with decreased risk of liver cancer (for CC versus AA: odds ratio (OR)?=?0.65, 95% confidence interval (CI) 0.47-0.89, P?=?0.007; for CC versus AA?+?AC: OR?=?0.65, 95% CI 0.48-0.89, P?=?0.006). Subgroup by race showed that the homozygote genotype CC of MTHFR rs1801131 polymorphism was significantly associated with decreased risk of liver cancer in Asians (CC versus AA: OR?=?0.64, 95% CI 0.46-0.90, P?=?0.010; for CC versus AA?+ AC: OR?=?0.63, 95% CI 0.45-0.88, P?=?0.007). However, the association in Caucasians was still unclear owing to the limited data available now. Thus, Asian individuals with the homozygote genotype CC of MTHFR rs1801131 polymorphism are significantly associated with decreased risk of liver cancer. The association in Caucasians needs further studies. PMID:24014085

  19. Genetic polymorphism of MTHFR C677T and premature coronary artery disease susceptibility: A meta-analysis.

    PubMed

    Hou, Xiaowen; Chen, Xin; Shi, Jingpu

    2015-07-01

    The association between 5, 10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism and premature coronary artery disease (PCAD) is controversial. To explore a more precise estimation of the association, a meta-analysis was conducted in the present study. The relevant studies were identified by searching PubMed, EMBASE, the Web of Science, Cochrane Collaboration Database, Chinese National Knowledge Infrastructure, Wanfang Database and China Biological Medicine up to November, 2014. The meta-analysis was performed by STATA 11. 21 studies with a total of 6912 subjects, including 2972 PCAD patients and 3940 controls. The pooled analysis showed that MTHFR C677T gene polymorphism was probably associated with PCAD (CT vs. CC: OR=1.13, 95% CI=1.01-1.27; dominant model: OR=1.16, 95% CI=1.04-1.29; recessive model: OR=1.19, 95% CI=1.00-1.40; allele analysis: OR=1.17, 95% CI=1.01-1.34). Subgroup analysis by plasma homocysteine concentration showed a significant association in the homocysteine >15?mol/L subgroup (CT vs. CC: OR=1.44, 95% CI=1.10-1.88; TT vs. CC: OR=2.51, 95% CI=1.12-5.63; dominant model: OR=1.51, 95% CI=1.16-1.96; recessive model: OR=2.33, 95% CI=1.05-5.20; allele analysis: OR=1.48, 95% CI=1.18-1.87). Subgroup analysis by continent displayed a significant association among the Asian population (CT vs. CC: OR=1.51, 95% CI=1.23-1.86; TT vs. CC: OR=2.81, 95% CI=1.87-4.23; dominant model: OR=1.65, 95% CI=1.35-2.01; recessive model: OR=2.22, 95% CI=1.53-3.21; allele analysis: OR=1.61, 95% CI=1.37-1.89). The statistical stability and reliability was demonstrated by sensitivity analysis and publication bias outcomes. In conclusion, the meta-analysis suggests that MTHFR C677T gene polymorphism may be associated with PCAD. PMID:25839940

  20. Radiographic predisposing factors for degenerative spondylolisthesis.

    PubMed

    Smorgick, Yossi; Mirovsky, Yigal; Fischgrund, Jeffrey S; Baker, Kevin C; Gelfer, Yael; Anekstein, Yoram

    2014-03-01

    This study was a retrospective radiographic study involving analysis of computed tomography scans obtained for patients with degenerative spondylolisthesis of the L4-L5 segment and a control group. The purpose of the study was to identify radiological predisposing factors for degenerative spondylolisthesis of the L4-L5 segment. The authors reviewed all computed tomography scans (N=3370) performed at their institution between January 2005 and December 2008. Eighty-four patients with degenerative spondylolisthesis were identified and compared with a control group regarding facet joint orientation, the presence of sacralization of the L5 vertebra, the presence of major degenerative changes in the L5-S1 disk space, and the location of the intercrestal line. There was a statistically significant difference between the 2 groups regarding facet joint orientation, with more sagittal facet joints in the degenerative spondylolisthesis group (56° and 54° in the right and left facets, respectively, in the study group, and 46° and 42° in the right and left facets, respectively, in the control group) (P<.001). There was no statistically significant difference between the 2 groups regarding the presence of sacralization of the L5 vertebra, the presence of major degenerative changes in the L5-S1 disk space, and the location of the intercrestal line relative to the lumbar spine. There is an association between sagittal orientation of the facet joints at the L4-L5 segment and degenerative spondylolisthesis at the same level. PMID:24762153

  1. MTHFR genotype and colorectal adenoma recurrence: data from a double blind placebo controlled clinical trial

    PubMed Central

    Levine, A. Joan; Wallace, Kristin; Tsang, Shirley; Haile, Robert W.; Saibil, Fred; Ahnen, Dennis; Cole, Bernard F.; Barry, Elizabeth L.; Munroe, David J; Ali, Iqbal U; Ueland, Per; Baron, John A.

    2009-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism. We ssessed the association between two common MTHFR variants, 677C>T and 1298A>C, and adenoma recurrence in the context of a randomized double blind clinical trial of aspirin use and folate supplementation. We used generalized linear regression to estimate risk ratios and 95% CIs for recurrence, adjusting for age, sex, clinical center, follow-up time, and treatment status. Neither MTHFR polymorphism was associated with overall or advanced adenoma recurrence. Compared to those with 2 wild type alleles, the relative risk for advanced adenoma was 0.75 (95% CI 0.36 to 1.55), for the MTHFR 677 TT genotype and 1.16 (95% CI 0.58–2.33) for the MTHFR 1298 CC genotype. The effect of folate supplementation on recurrence risk did not differ by genotype. Our findings indicate that MTHFR genotype does not change adenoma risk in a manner similar to its effect on colorectal cancer, and does not modify the effect of folate supplementation on metachronous adenoma risk. PMID:18768511

  2. Methylenetetrahydrofolate reductase (MTHFR) polymorphism A1298C (Glu429Ala) predicts decline in renal function over time in the African-American Study of Kidney Disease and Hypertension (AASK) Trial and Veterans Affairs Hypertension Cohort (VAHC)

    PubMed Central

    Salem, Rany M.; Lipkowitz, Michael S.; Bhatnagar, Vibha; Pandey, Braj; Schork, Nicholas J.; O’Connor, Daniel T.

    2012-01-01

    Background. Hyperhomocysteinemia is associated with increased venous thrombosis and cardiovascular disease (CVD). Mutations in the human methylenetetrahydrofolate reductase (MTHFR) gene have been associated with increased homocysteine levels and risks of CVD in various populations including those with kidney disease. Here, we evaluated the influence of MTHFR variants on progressive loss of kidney function. Methods. We analyzed 821 subjects with hypertensive nephrosclerosis from the longitudinal National Institute of Diabetes and Digestive and Kidney Diseases African-American Study of Kidney Disease and Hypertension (AASK) Trial to determine whether decline in glomerular filtration rate (GFR) over ?4.2 years was predicted by common genetic variation within MTHFR at non-synonymous positions C677T (Ala222Val) and A1298C (Glu429Ala) or by MTHFR haplotypes. The effect on GFR decline was then supported by a study of 1333 subjects from the San Diego Veterans Affairs Hypertension Cohort (VAHC), followed over ?4.5 years. Linear effect models were utilized to determine both genotype [single-nucleotide polymorphism (SNP)] and genotype (SNP)-by-time interactions. Results. In AASK, the polymorphism at A1298C predicted the rate of GFR decline: A1298/A1298 major allele homozygosity resulted in a less pronounced decline of GFR, with a significant SNP-by-time interaction. An independent follow-up study in the San Diego VAHC subjects supports that A1298/A1298 homozygotes have the greatest estimated GFR throughout the study. Haplotype analysis with C677T yielded concurring results. Conclusion. We conclude that the MTHFR-coding polymorphism at A1298C is associated with renal decline in African-Americans with hypertensive nephrosclerosis and is supported by a veteran cohort with a primary care diagnosis of hypertension. Further investigation is needed to confirm such findings and to determine what molecular mechanism may contribute to this association. PMID:21613384

  3. Mutations in LRRC50 Predispose Zebrafish and Humans to Seminomas

    PubMed Central

    Basten, Sander G.; van Rooijen, Ellen; Stoop, Hans; Babala, Nikolina; Logister, Ive; Heath, Zachary G.; Jonges, Trudy N.; Katsanis, Nicholas; Voest, Emile E.; van Eeden, Freek J.; Medema, Rene H.; Ketting, René F.; Schulte-Merker, Stefan; Looijenga, Leendert H. J.; Giles, Rachel H.

    2013-01-01

    Seminoma is a subclass of human testicular germ cell tumors (TGCT), the most frequently observed cancer in young men with a rising incidence. Here we describe the identification of a novel gene predisposing specifically to seminoma formation in a vertebrate model organism. Zebrafish carrying a heterozygous nonsense mutation in Leucine-Rich Repeat Containing protein 50 (lrrc50 also called dnaaf1), associated previously with ciliary function, are found to be highly susceptible to the formation of seminomas. Genotyping of these zebrafish tumors shows loss of heterozygosity (LOH) of the wild-type lrrc50 allele in 44.4% of tumor samples, correlating with tumor progression. In humans we identified heterozygous germline LRRC50 mutations in two different pedigrees with a family history of seminomas, resulting in a nonsense Arg488* change and a missense Thr590Met change, which show reduced expression of the wild-type allele in seminomas. Zebrafish in vivo complementation studies indicate the Thr590Met to be a loss-of-function mutation. Moreover, we show that a pathogenic Gln307Glu change is significantly enriched in individuals with seminoma tumors (13% of our cohort). Together, our study introduces an animal model for seminoma and suggests LRRC50 to be a novel tumor suppressor implicated in human seminoma pathogenesis. PMID:23599692

  4. Insights on the structural perturbations in human MTHFR Ala222Val mutant by protein modeling and molecular dynamics.

    PubMed

    Abhinand, P A; Shaikh, Faraz; Bhakat, Soumendranath; Radadiya, Ashish; Bhaskar, L V K S; Shah, Anamik; Ragunath, P K

    2016-04-01

    Methylenetetrahydrofolate reductase (MTHFR) protein catalyzes the only biochemical reaction which produces methyltetrahydrofolate, the active form of folic acid essential for several molecular functions. The Ala222Val polymorphism of human MTHFR encodes a thermolabile protein associated with increased risk of neural tube defects and cardiovascular disease. Experimental studies have shown that the mutation does not affect the kinetic properties of MTHFR, but inactivates the protein by increasing flavin adenine dinucleotide (FAD) loss. The lack of completely solved crystal structure of MTHFR is an impediment in understanding the structural perturbations caused by the Ala222Val mutation; computational modeling provides a suitable alternative. The three-dimensional structure of human MTHFR protein was obtained through homology modeling, by taking the MTHFR structures from Escherichia coli and Thermus thermophilus as templates. Subsequently, the modeled structure was docked with FAD using Glide, which revealed a very good binding affinity, authenticated by a Glide XP score of -10.3983 (kcal mol(-1)). The MTHFR was mutated by changing Alanine 222 to Valine. The wild-type MTHFR-FAD complex and the Ala222Val mutant MTHFR-FAD complex were subjected to molecular dynamics simulation over 50 ns period. The average difference in backbone root mean square deviation (RMSD) between wild and mutant variant was found to be ~.11 Å. The greater degree of fluctuations in the mutant protein translates to increased conformational stability as a result of mutation. The FAD-binding ability of the mutant MTHFR was also found to be significantly lowered as a result of decreased protein grip caused by increased conformational flexibility. The study provides insights into the Ala222Val mutation of human MTHFR that induces major conformational changes in the tertiary structure, causing a significant reduction in the FAD-binding affinity. PMID:26273990

  5. MTHFR C677T genotype as a risk factor for epilepsy including post-traumatic epilepsy in a representative military cohort.

    PubMed

    Scher, Ann I; Wu, Holly; Tsao, Jack W; Blom, Henk J; Feit, Preethy; Nevin, Remington L; Schwab, Karen A

    2011-09-01

    The well-studied C677T variant in the methylenetetrahydrofolate reductase (MTHFR) enzyme is a biologically plausible genetic risk factor for seizures or epilepsy. First, plasma/serum levels of homocysteine, a pro-convulsant, are moderately elevated in individuals with the homozygote TT genotype. Furthermore, the TT genotype has been previously linked with migraine with aura-a comorbid condition-and with alcohol withdrawal seizures. Finally, several small studies have suggested that the TT genotype may be overrepresented in epilepsy patients. In this study, we consider whether the MTHFR C677T or A1298C variants are associated with risk of epilepsy including post-traumatic epilepsy (PTE) in a representative military cohort. Study subjects were selected from the cohort of military personnel on active duty during the years 2003 through 2007 who had archived serum samples at the DoD Serum Repository, essentially all active duty personnel during this time frame. We randomly selected 800 epilepsy patients and 800 matched controls based on ICD-9-CM diagnostic codes. We were able to isolate sufficient genetic material from the archived sera to genotype approximately 85% of our study subjects. The odds of epilepsy were increased in subjects with the TT versus CC genotype (crude OR=1.52 [1.04-2.22], p=0.031; adjusted OR=1.57 [1.07-2.32], p=0.023). In our sensitivity analysis, risk was most evident for patients with repeated rather than single medical encounters for epilepsy (crude OR=1.85 [1.14-2.97], p=0.011, adjusted OR=1.95 [1.19-3.19], p=0.008), and particularly for PTE (crude OR=3.14 [1.41-6.99], p=0.005; adjusted OR=2.55 [1.12-5.80], p=0.026). Our early results suggest a role for the common MTHFR C677T variant as a predisposing factors for epilepsy including PTE. Further exploration of baseline homocysteine and folate levels as predictors of seizure risk following traumatic brain injury is warranted. PMID:21787169

  6. Association between MTHFR C677T polymorphism and diabetic nephropathy in the Chinese population: An updated meta-analysis and review.

    PubMed

    Xiong, Xuan; Lin, Xiao-Kun; Xiao, Xiao; Qin, Dan-Ping; Zhou, Dao-Yuan; Hu, Jian-Guang; Liu, Yan; Zhong, Xiao-Shi

    2016-01-01

    To clarify the effects of MTHFR C677T polymorphism on the risk of diabetic nephropathy (DN) in the Chinese population, an updated meta-analysis was performed. Related studies were identified from PubMed, Springer Link, Ovid and Chinese Databases up to 24 February 2015. A total of 15 studies including 1227 DN cases, 586 healthy controls and 1277 diabetes mellitus (DM) controls were involved in this meta-analysis. Overall, a significantly elevated risk of DN was associated with all variants of MTHFR C677T when compared with the healthy group (T vs C, odds ratio (OR) = 2.22, 95% confidence interval (CI) = 1.88-2.61; TT vs CC, OR = 4.22, 95% CI = 3.02-5.90; TT + CT vs CC, OR = 2.62, 95% CI = 2.07-3.31; TT vs CC + CT, OR = 2.81, 95% CI = 2.08-3.81) or DM (T vs C, OR = 1.78, 95% CI = 1.59-2.00; TT vs CC, OR = 2.95, 95% CI = 2.33-3.73; TT + CT vs CC, OR = 1.93, 95% CI = 1.63-2.29; TT vs CC + CT, OR = 2.31, 95% CI = 1.87-2.84). In subgroup analyses stratified by ethnicity and geographic areas, it revealed the significant results in Chinese Han, in North and South China. The risk conferred by MTHFR C677T polymorphism is higher in North China than in South China. This meta-analysis showed that the MTHFR C677T variants may influence DN risk in Chinese, and further studies with gene-gene and gene-environment interactions are required for definite conclusions. PMID:26072975

  7. MTHFR C677T polymorphism and anatomopathological characteristics with prognostic significance in sporadic colorectal cancer.

    PubMed

    Delgado-Plasencia, Luciano; Álvarez-Argüelles, Hugo; Salido-Ruiz, Eduardo; Castro-Peraza, M Elisa; Bravo-Gutiérrez, Alberto; Fernández-Peralta, Antonia; González-Aguilera, Juan; Alarcó-Hernández, Antonio; Medina-Arana, Vicente

    2015-12-01

    Methylenetetrahydrofolate reductase (MTHFR) plays a key role in folate metabolism, and folate is implicated in carcinogenesis due to its role in DNA methylation, repair and synthesis. The MTHFR C677T polymorphism is associated with decreased risk of CRC and increased sensitivity to 5-FU treatment. The present study addressed the relationship between this polymorphism and histopathological and immunohistochemical characteristics of prognostic significance in 50 patients from the Canary Islands. No differences were found between the MTHFR C677T genotypes with respect to tumor budding, tumor necrosis, desmoplastic fibrosis and tumoral eosinophilia. No significant differences were found in Ki-67, bcl-2 (cytoplasmic and nuclear), CD31, CD3+ T lymphocytes (both stromal and intraepithelial) and peritumoral CD20+ B lymphocytes. In carriers of the MTHFR CC variant, tumor margins were infiltrative more frequently (68.7%) than in CT+TT carriers (33.3%, p=0.03). In addition, wild-type CC genotype showed stromal CD20+ B lymphocytes (68.8%) more often than CT+TT carriers (33.3%, p=0.03). Both parameters indicate a better tumor prognosis when the MTHFR 677T variant is present. PMID:26564107

  8. Plasma folate, methylenetetrahydrofolate reductase (MTHFR), and colorectal cancer risk in three large nested case-control studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Few prospective studies have examined the associations between blood levels of folate, in conjunction with methylenetetrahydrofolate reductase (MTHFR) polymorphisms, and colorectal cancer. We evaluated the associations between plasma folate, MTHFR C677T, and A1298C, and colorectal cancer in three la...

  9. Prevalence of MTHFR C677T single nucleotide polymorphism in genetically isolated populations in Jordan.

    PubMed

    Dajani, Rana; Fathallah, Raja; Arafat, Ala; AbdulQader, Mohammed Emad; Hakooz, Nancy; Al-Motassem, Yousef; El-Khateeb, Mohammad

    2013-10-01

    Methylenetetrahydrofolate reductase (MTHFR) C677T single nucleotide polymorphism is a major inherited risk factor of venous thromboembolism. We sought to determine its prevalence in genetically isolated populations of Chechens and Circassians in Jordan. The MTHFR C677T mutation was analyzed from blood samples taken from 120 random unrelated Chechens and 72 Circassians. The prevalence of the MTHFR mutation in the Chechen population was 27.5% (allele frequency 15%); the prevalence among the Circassians was 50% (allele frequency 29.2%). The prevalence in the Chechen population is similar to that in Jordan and other world populations, but it is higher in the Circassian population. This study will contribute to understanding the interaction between genetic and environmental risk factors underlying thrombosis and will be useful in deciding which genetic variants should be tested in a clinical genetic testing service. PMID:23749065

  10. A novel lateral flow assay based on GoldMag nanoparticles and its clinical applications for genotyping of MTHFR C677T polymorphisms

    NASA Astrophysics Data System (ADS)

    Hui, Wenli; Zhang, Sinong; Zhang, Chao; Wan, Yinsheng; Zhu, Juanli; Zhao, Gang; Wu, Songdi; Xi, Dujuan; Zhang, Qinlu; Li, Ningning; Cui, Yali

    2016-02-01

    Current techniques for single nucleotide polymorphism (SNP) detection require tedious experimental procedures and expensive and sophisticated instruments. In this study, a visual genotyping method has been successfully established via combining ARMS-PCR with gold magnetic nanoparticle (GoldMag)-based lateral flow assay (LFA) and applied to the genotyping of methylenetetrahydrofolate reductase (MTHFR) C677T. C677T substitution of the gene MTHFR leads to an increased risk of diseases. The genotyping result is easily achievable by visual observation within 5 minutes after loading of the PCR products onto the LFA device. The system is able to accurately assess a broad detection range of initial starting genomic DNA amounts from 5 ng to 1200 ng per test sample. The limit of detection reaches 5 ng. Furthermore, our PCR-LFA system was applied to clinical trials for screening 1721 individuals for the C677T genotypes. The concordance rate of the genotyping results detected by PCR-LFA was up to 99.6% when compared with the sequencing results. Collectively, our PCR-LFA has been proven to be rapid, accurate, sensitive, and inexpensive. This new method is highly applicable for C677T SNP screening in laboratories and clinical practices. More promisingly, it could also be extended to the detection of SNPs of other genes.

  11. A novel lateral flow assay based on GoldMag nanoparticles and its clinical applications for genotyping of MTHFR C677T polymorphisms.

    PubMed

    Hui, Wenli; Zhang, Sinong; Zhang, Chao; Wan, Yinsheng; Zhu, Juanli; Zhao, Gang; Wu, Songdi; Xi, Dujuan; Zhang, Qinlu; Li, Ningning; Cui, Yali

    2016-02-14

    Current techniques for single nucleotide polymorphism (SNP) detection require tedious experimental procedures and expensive and sophisticated instruments. In this study, a visual genotyping method has been successfully established via combining ARMS-PCR with gold magnetic nanoparticle (GoldMag)-based lateral flow assay (LFA) and applied to the genotyping of methylenetetrahydrofolate reductase (MTHFR) C677T. C677T substitution of the gene MTHFR leads to an increased risk of diseases. The genotyping result is easily achievable by visual observation within 5 minutes after loading of the PCR products onto the LFA device. The system is able to accurately assess a broad detection range of initial starting genomic DNA amounts from 5 ng to 1200 ng per test sample. The limit of detection reaches 5 ng. Furthermore, our PCR-LFA system was applied to clinical trials for screening 1721 individuals for the C677T genotypes. The concordance rate of the genotyping results detected by PCR-LFA was up to 99.6% when compared with the sequencing results. Collectively, our PCR-LFA has been proven to be rapid, accurate, sensitive, and inexpensive. This new method is highly applicable for C677T SNP screening in laboratories and clinical practices. More promisingly, it could also be extended to the detection of SNPs of other genes. PMID:26804455

  12. Methylenetetrahydrofolate Reductase Gene Polymorphisms in Children with Attention Deficit Hyperactivity Disorder

    PubMed Central

    Gokcen, Cem; Kocak, Nadir; Pekgor, Ahmet

    2011-01-01

    Objective: The purpose of this study was to evaluate the relationship between 5,10- methylenetetrahydrofolate reductase (MTHFR) polymorphisms and Attention Deficit Hyperactivity Disorder (ADHD) in a sample of Turkish children. Study Design: MTHFR gene polymorphisms were assessed in 40 patients with ADHD and 30 healty controls. Two mutations in the MTHFR gene were investigated using polymerase chain reactions and restriction fragment length polymorphisms. Results: Although there were no statistically significant differences in genotype distributions of the C677T alleles between the ADHD and the control groups (p=0,678) but the genotypic pattern of the distributions of the A1298C alleles was different between the ADHD patients and the controls (p=0,033). Conclusions: Preliminary data imply a possible relationship between A1298C MTHFR polymorphisms and the ADHD. PMID:21897766

  13. Lack of association between MTHFR Ala222Val and Glu429Ala polymorphisms and bladder cancer risk: A meta-analysis of case-control studies

    PubMed Central

    SHI, RONG; ZHAO, ZHEN; ZHOU, HUI; ZHOU, JUEYU; TAN, WANLONG

    2014-01-01

    Bladder cancer is a commom malignancy in the urinary tract that is influenced by genetic and environmental factors. The role of functional polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene with bladder cancer risk remains to be determined. This meta-analysis was performed to derive a more precise estimation of MTHFR Ala222Val and Glu429Ala polymorphisms and bladder cancer risk. Data were collected with the last report up to September 2013. A total of 3,463 cases and 3,927 controls for Ala222Val, and 3,177 cases and 3,502 controls for Glu429Ala were analyzed. The pooled odds ratios (ORs) and 95% confidence interval (CI) were estimated for the association with bladder cancer risk. Overall, no significant associations of Ala222Val and Glu429Ala polymorphisms with bladder cancer risk were found (for Ala222Val: Val/Val vs. Ala/Ala: OR, 1.02; 95% CI: 0.80–1.29; Val/Ala vs. Ala/Ala: OR, 1.02; 95% CI: 0.92–1.12; dominant model: OR, 1.01; 95% CI: 0.87–1.17; recessive model: OR, 1.00; 95% CI: 0.87–1.15; and for Glu429Ala: Ala/Ala vs. Glu/Glu: OR, 1.11; 95% CI: 0.78–1.58; Ala/Glu vs. Glu/Glu: OR, 1.16; 95% CI: 0.95–1.40; dominant model: OR, 1.15; 95% CI: 0.94–1.41; recessive model: OR, 0.96; 95% CI: 0.79–1.15). In stratified analyses by ethnicity, significant associations were observed for Glu429Ala polymorphism in individuals of Middle Eastern descent (Ala/Glu vs. Glu/Glu: OR, 2.11; 95% CI: 1.26–3.53; dominant model: OR, 2.16; 95% CI: 1.16–4.01; recessive model: OR, 1.82; 95% CI: 1.11–3.01). This meta-analysis demonstrated that overall there was no association of MTHFR Ala222Val and Glu429Ala polymorphisms with bladder cancer risk. However, in the stratified analysis by ethnicity the MTHFR Glu429Ala polymorphism was significantly associated with increased bladder cancer risk in individuals of Middle Eastern descent. PMID:24748982

  14. Detecting disease-predisposing variants: The haplotype method

    SciTech Connect

    Valdes, A.M.; Thomson, G.

    1997-03-01

    For many HLA-associated diseases, multiple alleles - and, in some cases, multiple loci - have been suggested as the causative agents. The haplotype method for identifying disease-predisposing amino acids in a genetic region is a stratification analysis. We show that, for each haplotype combination containing all the amino acid sites involved in the disease process, the relative frequencies of amino acid variants at sites not involved in disease but in linkage disequilibrium with the disease-predisposing sites are expected to be the same in patients and controls. The haplotype method is robust to mode of inheritance and penetrance of the disease and can be used to determine unequivocally whether all amino acid sites involved in the disease have not been identified. Using a resampling technique, we developed a statistical test that takes account of the nonindependence of the sites sampled. Further, when multiple sites in the genetic region are involved in disease, the test statistic gives a closer fit to the null expectation when some - compared with none - of the true predisposing factors are included in the haplotype analysis. Although the haplotype method cannot distinguish between very highly correlated sites in one population, ethnic comparisons may help identify the true predisposing factors. The haplotype method was applied to insulin-dependent diabetes mellitus (IDDM) HLA class II DQA1-DQB1 data from Caucasian, African, and Japanese populations. Our results indicate that the combination DQA1 No. 52 (Arg predisposing) DQB1 No. 57 (Asp protective), which has been proposed as an important IDDM agent, does not include all the predisposing elements. With rheumatoid arthritis HLA class H DRB1 data, the results were consistent with the shared-epitope hypothesis. 35 refs., 2 figs., 6 tabs.

  15. Risk of colorectal cancer associated with the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in the Kashmiri population.

    PubMed

    Sameer, A S; Shah, Z A; Nissar, S; Mudassar, S; Siddiqi, M A

    2011-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA synthesis, DNA repair and DNA methylation. The two common functional polymorphisms of MTHFR, 677 C?T and 1298 A?C, have been shown to impact various diseases, including cancer. The 677 C?T polymorphism has been widely investigated in different cancers and has been implicated as a risk factor for the development of various cancers. We investigated MTHFR C677T genotype frequency in colorectal cancer cases in the Kashmiri population and correlated this information with the known clinicopathological characters of colorectal cancer, in a case-control study. Eighty-six colorectal cancer cases were studied for MTHFR C677T polymorphism, compared to 160 controls taken from the general population, employing the PCR-RFLP technique. We found the frequency of the three different genotypes of MTHFR in our ethnic Kashmir population, i.e., CC, CT and TT, to be 68.6, 20.9 and 10.4% among colorectal cancer cases and 75.6, 16.9 and 7.5% among the general control population, respectively. There was a significant association between the MTHFR TT genotype and colorectal cancer in the higher age group. We conclude that the MTHFR C677T polymorphism slightly increases the risk for colorectal cancer development in our ethnic Kashmir population. PMID:21732284

  16. [C677T AND A1298C ALLELE POLYMORPHISM GENE OF METHYLENETETRAHYDRAFOLATEREDUCTASE IN PATIENTS WITH NONALCOHOLIC FATTY LIVER DISEASE AND TYPE 2 DIABETES].

    PubMed

    Orlovskiy, V; Kuchma, N; Murenets, N; Orlovskiy, A

    2015-10-01

    The article presents the results of the study C677T and A1298C polymorphisms of MTHFR gene and their influence on plasma homocysteine levels in patients with nonalcoholic fatty liver disease (NAFLD). The study involved 100 patients with NAFLD and 40 apparently healthy individuals (control group). Determination of allelic polymorphism was performed by polymerase chain reaction with the detection results of hybridization by fluorescence in real-time. Determination of plasma homocysteine levels was performed by ELISA. As a result, studies have not found significant differences in the distribution of genotypes investigated C677T and A1298C MTHFR gene between patients with NAFLD and control group. We have detected statistically significant relationship between the level of homocysteine plasma C677T polymorphism of the MTHFR gene in patients with NAFLD and lack of connection with the A1298C polymorphism of the gene MTHFR. PMID:26483372

  17. Association of PHB 1630 C>T and MTHFR 677 C>T polymorphisms with breast and ovarian cancer risk in BRCA1/2 mutation carriers: results from a multicenter study

    PubMed Central

    Jakubowska, A; Rozkrut, D; Antoniou, A; Hamann, U; Scott, R J; McGuffog, L; Healy, S; Sinilnikova, O M; Rennert, G; Lejbkowicz, F; Flugelman, A; Andrulis, I L; Glendon, G; Ozcelik, H; Thomassen, M; Paligo, M; Aretini, P; Kantala, J; Aroer, B; von Wachenfeldt, A; Liljegren, A; Loman, N; Herbst, K; Kristoffersson, U; Rosenquist, R; Karlsson, P; Stenmark-Askmalm, M; Melin, B; Nathanson, K L; Domchek, S M; Byrski, T; Huzarski, T; Gronwald, J; Menkiszak, J; Cybulski, C; Serrano, P; Osorio, A; Cajal, T R; Tsitlaidou, M; Benítez, J; Gilbert, M; Rookus, M; Aalfs, C M; Kluijt, I; Boessenkool-Pape, J L; Meijers-Heijboer, H E J; Oosterwijk, J C; van Asperen, C J; Blok, M J; Nelen, M R; van den Ouweland, A M W; Seynaeve, C; van der Luijt, R B; Devilee, P; Easton, D F; Peock, S; Frost, D; Platte, R; Ellis, S D; Fineberg, E; Evans, D G; Lalloo, F; Eeles, R; Jacobs, C; Adlard, J; Davidson, R; Eccles, D; Cole, T; Cook, J; Godwin, A; Bove, B; Stoppa-Lyonnet, D; Caux-Moncoutier, V; Belotti, M; Tirapo, C; Mazoyer, S; Barjhoux, L; Boutry-Kryza, N; Pujol, P; Coupier, I; Peyrat, J-P; Vennin, P; Muller, D; Fricker, J-P; Venat-Bouvet, L; Johannsson, O Th; Isaacs, C; Schmutzler, R; Wappenschmidt, B; Meindl, A; Arnold, N; Varon-Mateeva, R; Niederacher, D; Sutter, C; Deissler, H; Preisler-Adams, S; Simard, J; Soucy, P; Durocher, F; Chenevix-Trench, G; Beesley, J; Chen, X; Rebbeck, T; Couch, F; Wang, X; Lindor, N; Fredericksen, Z; Pankratz, V S; Peterlongo, P; Bonanni, B; Fortuzzi, S; Peissel, B; Szabo, C; Mai, P L; Loud, J T; Lubinski, J

    2012-01-01

    Background: The variable penetrance of breast cancer in BRCA1/2 mutation carriers suggests that other genetic or environmental factors modify breast cancer risk. Two genes of special interest are prohibitin (PHB) and methylene-tetrahydrofolate reductase (MTHFR), both of which are important either directly or indirectly in maintaining genomic integrity. Methods: To evaluate the potential role of genetic variants within PHB and MTHFR in breast and ovarian cancer risk, 4102 BRCA1 and 2093 BRCA2 mutation carriers, and 6211 BRCA1 and 2902 BRCA2 carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2 (CIMBA) were genotyped for the PHB 1630 C>T (rs6917) polymorphism and the MTHFR 677 C>T (rs1801133) polymorphism, respectively. Results: There was no evidence of association between the PHB 1630 C>T and MTHFR 677 C>T polymorphisms with either disease for BRCA1 or BRCA2 mutation carriers when breast and ovarian cancer associations were evaluated separately. Analysis that evaluated associations for breast and ovarian cancer simultaneously showed some evidence that BRCA1 mutation carriers who had the rare homozygote genotype (TT) of the PHB 1630 C>T polymorphism were at increased risk of both breast and ovarian cancer (HR 1.50, 95%CI 1.10–2.04 and HR 2.16, 95%CI 1.24–3.76, respectively). However, there was no evidence of association under a multiplicative model for the effect of each minor allele. Conclusion: The PHB 1630TT genotype may modify breast and ovarian cancer risks in BRCA1 mutation carriers. This association need to be evaluated in larger series of BRCA1 mutation carriers. PMID:22669161

  18. Association study between methylenetetrahydrofolate reductase gene polymorphisms and Graves' disease.

    PubMed

    Mao, Renfang; Fan, Yihui; Zuo, Lulu; Geng, Dongfeng; Meng, Fantao; Zhu, Jing; Li, Qiang; Qiao, Hong; Jin, Yan; Bai, Jing; Fu, Songbin

    2010-10-01

    5,10-Methylenetetrahydrofolate reductase (MTHFR) catalyzes the metabolism of folate and nucleotides, which are essential for DNA synthesis and methylation. It is highly polymorphic, and its variant genotypes result in lower enzymatic activity and higher plasma homocysteine. Previous studies have provided evidence that a high prevalence of MTHFR gene polymorphisms is frequently detected in patients with autoimmune disease, suggesting a novel genetic association with autoimmune disorders. However, the genetic association between MTHFR and Graves' disease (GD), one of the most common autoimmune diseases, has not been studied. Here, we designed a clinic-based case-control study including 199 GD cases and 235 healthy controls to examine the associations between three common MTHFR polymorphisms (i.e., C677T, A1298C, and G1793A) and GD. Surprisingly, logistic regression analysis shows MTHFR 677CT?+?TT genotypes are associated with an approximately 42% reduction in the risk of GD in women (adjusted OR?=?0.58, 95% CI?=?0.3-0.9), compared to the CC genotype, indicating a significant protective effect of 677CT?+?TT genotypes. Our result provides epidemiological evidence that MTHFR mutation (C677T) protects women from GD. The protective effect, possibly obtained by influencing DNA methylation, should be confirmed in a large number of cohorts. PMID:20941748

  19. MTHFR polymorphisms involved in vitamin B12 deficiency associated with atrophic gastritis.

    PubMed

    Palladino, Mariangela; Chiusolo, Patrizia; Reddiconto, Giovanni; Marietti, Sara; De Ritis, Daniela; Leone, Giuseppe; Sica, Simona

    2009-10-01

    Genetic polymorphisms affecting methylentetrahydrofolate reductase (MTHFR) activity may influence hematological and neurological dysfunction in cobalamin-deficient patients. We studied the prevalence of C677T and A1298C polymorphisms by analyzing genomic DNA in 30 cobalamin-deficient patients. No significant difference was found in 677 and 1298 genotype distribution with respect to hematological parameters, B12 and folate levels, and neurological symptoms. The two MTHFR polymorphisms were not protective against anemia or neurological dysfunction in patients with cobalamin deficiency; however, we found evidence of a significant increase in atrophic gastritis in the 677TT group (P = 0.009) but not for the 1298CC genotype. Based on observations that inadequate cobalamin intake and reduced MTHFR activity might be significant risk factors for gastric cancer, and the increased risk of gastric cancer shown in patients affected by atrophic gastritis, we speculate that concomitant atrophic gastritis and impaired MTHFR function could have a role in the development of gastric cancer. PMID:19521764

  20. Germline duplication of ATG2B and GSKIP predisposes to familial myeloid malignancies.

    PubMed

    Saliba, Joseph; Saint-Martin, Cécile; Di Stefano, Antonio; Lenglet, Gaëlle; Marty, Caroline; Keren, Boris; Pasquier, Florence; Valle, Véronique Della; Secardin, Lise; Leroy, Gwendoline; Mahfoudhi, Emna; Grosjean, Sarah; Droin, Nathalie; Diop, M'boyba; Dessen, Philippe; Charrier, Sabine; Palazzo, Alberta; Merlevede, Jane; Meniane, Jean-Côme; Delaunay-Darivon, Christine; Fuseau, Pascal; Isnard, Françoise; Casadevall, Nicole; Solary, Eric; Debili, Najet; Bernard, Olivier A; Raslova, Hana; Najman, Albert; Vainchenker, William; Bellanné-Chantelot, Christine; Plo, Isabelle

    2015-10-01

    No major predisposition gene for familial myeloproliferative neoplasms (MPN) has been identified. Here we demonstrate that the autosomal dominant transmission of a 700-kb duplication in four genetically related families predisposes to myeloid malignancies, including MPN, frequently progressing to leukemia. Using induced pluripotent stem cells and primary cells, we demonstrate that overexpression of ATG2B and GSKIP enhances hematopoietic progenitor differentiation, including of megakaryocytes, by increasing progenitor sensitivity to thrombopoietin (TPO). ATG2B and GSKIP cooperate with acquired JAK2, MPL and CALR mutations during MPN development. Thus, the germline duplication may change the fitness of cells harboring signaling pathway mutations and increases the probability of disease development. PMID:26280900

  1. Evaluation of Gestational Diabetes Mellitus Risk in South Indian Women Based on MTHFR (C677T) and FVL (G1691A) Mutations

    PubMed Central

    Khan, Imran Ali; Shaik, Noor Ahmad; Kamineni, Vasundhara; Jahan, Parveen; Hasan, Qurratulain; Rao, Pragna

    2015-01-01

    We aimed to scrutinize the extent to which single amino acid substitutions in the MTHFR and factor V Leiden (FVL) genes affect the risk of gestational diabetes mellitus (GDM) in pregnant women of South Indian descendant. This case–control study was implemented once the ethical approval has been obtained. Overall, 237 women were recruited in this study: 137 had been diagnosed with GDM and the remaining 100 women were used as normal controls or non-GDM. The diagnosis of GDM was confirmed with biochemical analysis, i.e., GCT and oral glucose tolerance tests. Five milliliters of peripheral blood was collected and used for biochemical and molecular analyses. DNA was isolated, and genotyping for MTHFR (C677T) and FVL (G1691A) mutations was performed using PCR–RFLP. FVL (G1691A) locus was not polymorphic in the investigated sample. There was no significant difference in the allele and genotype frequencies of C677T polymorphism between GDM and non-GDM women (p?=?0.8892). PMID:26000264

  2. Methylenetetrahydrofolate Reductase (MTHFR) Polymorphisms and Susceptibility for Cervical Lesions: A Meta-Analysis

    PubMed Central

    Liu, Xiaojiao; Yang, Pei

    2012-01-01

    Background The association between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and the susceptibility to cervical lesions was unclear. This study was designed to investigate their precise association using a large-scale meta-analysis. Methods The previous 16 studies were identified by searching PubMed, Embase and CBM databases. The crude odds ratios and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the MTHFR C677T/A1298C polymorphisms and the susceptibility to the cervical lesions. The subgroup analyses were made on the following: pathological history, geographic region, ethnicity, source of controls and source of DNA for genotyping. Results Neither of the polymorphisms had a significant association with the susceptibility to the cervical lesions in all genetic models. Similar results were found in the subgroup analyses. No association was found between the MTHFR C677T polymorphism and the cervical lesions in the Asia or the America populations though a significant inverse association was found in the Europe population (additive model: P?=?0.006, OR?=?0.83, 95% CI?=?0.72–0.95; CT vs. CC: P?=?0.05, OR?=?0.83, 95% CI?=?0.69–1.00; TT vs. CC: P?=?0.05, OR?=?0.73, 95% CI?=?0.53–1.00). Interestingly, women with the MTHFR A1298C polymorphisms had a marginally increased susceptibility to invasive cancer (ICC) when compared with no carriers but no statistically significant difference in the dominant model (P?=?0.06, OR?=?1.21, 95% CI?=?0.99–1.49) and AC vs. AA (P?=?0.09, OR?=?1.21, 95% CI?=?0.97–1.51). Conclusions The MTHFR C677T and A1298C polymorphisms may not increase the susceptibility to cervical lesions. However, the meta-analysis reveals a negative association between the MTHFR C677T polymorphisms and the cervical lesions, especially in the European populations. The marginal association between the MTHFR A1298C polymorphisms and the susceptibility to cervical cancer requires a further study. PMID:23285018

  3. Moraxella keratitis: predisposing factors and clinical review of 95 cases

    PubMed Central

    Das, S; Constantinou, M; Daniell, M; Taylor, H R

    2006-01-01

    Aim To analyse the clinical presentation, identify predisposing risk factors and evaluate the outcome of treatment of Moraxella keratitis. Methods A retrospective analysis was carried out of culture?proved cases of Moraxella keratitis from hospital records during a 10?year period (from December 1995 to November 2005) at the Corneal Unit of the Royal Victorian Eye and Ear Hospital, Melbourne, Australia. Results 95 episodes of Moraxella keratitis were identified in 92 patients. 3 (3.2%) patients had recurrent keratitis. The mean age of the patients was 70 (range 17–93)?years. Multiple predisposing factors were identified in 23 (24%) eyes, including corneal graft (n?=?15), previous herpes keratitis (n?=?15) and eye lid diseases (n?=?15). Adjunctive procedures were carried out in 42 eyes. These included botulinum toxin injection (n?=?17), tarsorraphy (n?=?12), penetrating keratoplasty (n?=?8), enucleation (n?=?3), tissue adhesive and bandage contact lens (n?=?4), and conjunctival flap (n?=?5). Polymicrobial infection was present in 17 eyes. Final visual acuity was counting finger or less in 25 (26%) eyes. Conclusions Local ocular predisposing factors play a major role in Moraxella keratitis. This infection has a poor visual outcome attributable to both the nature of the infection and the predisposing factors. PMID:16825274

  4. Meta-analysis of associations between MTHFR and GST polymorphisms and susceptibility to multiple sclerosis.

    PubMed

    Lee, Young Ho; Seo, Young Ho; Kim, Jae-Hoon; Choi, Sung Jae; Ji, Jong Dae; Song, Gwan Gyu

    2015-11-01

    We examined whether methylenetetrahydrofolate reductase (MTHFR) and glutathione S-transferase (GST) polymorphisms are associated with susceptibility to multiple sclerosis (MS). We performed a meta-analysis on the association between MS and the following genotypes: MTHFR C677T, A1298C, and GSTP1 A313G polymorphisms, and GSTM1 and GSTT1 null alleles. Fifteen comparisons involving 2,486 patients and 2,861 controls were considered. Meta-analysis of all study subjects considered together showed no association between MS and the MTHFR 677 T allele (OR = 1.014, 95 % CI 0.803-1.280, p = 0.909). Stratification by ethnicity showed no similar association in Caucasian and Arab populations. Likewise, no link was found between MS and the MTHFR 1298 C allele in the total data (OR = 2.477, 95 % CI 0.507-12.10, p = 0.263), nor when it was stratified by ethnicity. No association with MS was observed in relation to the GSTM1 null genotype in Caucasian populations (OR = 1.229, 95 % CI 0.693-2.181, p = 0.481), nor with the GSTP1 A313G polymorphism (OR for G allele = 1.133, 95 % CI 0.903-1.421, p = 0.281). However, there was an association between MS and the GSTT1 null genotype in data obtained from Caucasian populations (OR = 1.945, 95 % CI 1.452-2.605, p = 8.6 × 10(-7)). GSTT1 null genotype is associated with MS in Caucasian populations; however, no association was found between MS and polymorphisms of MTHFR, GSTM1, and GSTP1. PMID:26150166

  5. Association between MTHFR A1298C polymorphism and hepatocellular carcinoma risk

    PubMed Central

    Zhang, Haiyan; Li, Guang; Zhang, Zhen

    2015-01-01

    Background: Hepatocarcinogenesis is a complex process that is influenced by many factors. Several studies have investigated the relationship between MTHFR A1298C polymorphism and hepatocellular carcinoma (HCC) risk, but the results are inconsistent. Therefore, we performed a meta-analysis covering a large sample size to address this controversy. Methods: Eligible studies were searched using PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI) databases. A total of 7 studies from 6 publications with 2035 cases and 3096 controls were included. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) was calculated by the fixed or random effects to evaluate the correlation between MTHFR A1298C polymorphism and HCC risk. The Q statistic and I2 statistic were used to assess the statistical heterogeneity among studies. Publication bias was evaluated by Egger’s linear regression test and Begg’s funnel plot. Results: In present study, the results showed that MTHFR A1298C polymorphism was not significantly associated with risk of HCC based on CC + AC vs. AA genetic model (OR=1.01, 95% CI=0.90-1.13). Similarly, in the subgroup analysis by ethnicity, no significant HCC risk was found in Asian population (OR=1.02, 95% CI=0.91-1.14). In the subgroup analysis based on source of control, we found that MTHFR A1298C polymorphism showed no effects on the occurrence of HCC in the population-based (PB) and hospital-based (HB) group (OR=0.97, 95% CI=0.83-1.15; OR=1.04, 95% CI=0.89-1.21). Conclusion: This meta-analysis suggested that MTHFR A1298C polymorphism may not be a risk factor for HCC. PMID:26309569

  6. Significant impact of MTHFR C677T polymorphism on plasma homovanillic acid (HVA) levels among alcohol-dependent patients.

    PubMed

    Lutz, Ulrich C; Batra, Anil; Wiatr, Gerlinde; Machicao, Fausto; Kolb, Werner; Maurer, Sandra; Buchkremer, Gerhard; Köhnke, Michael D

    2007-03-01

    The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) synthesizes 5-methyltetrahydrofolate. It plays a critical role in homocysteine metabolism. A high impact of MTHFR C677T polymorphism on plasma homocysteine levels has been observed among alcoholics. Recent studies indicate that homocysteine has toxic effects on dopaminergic neurons. Thus it lowers levels of homovanillic acid (HVA) in the striatal region in rats. Alcoholics had significantly lower plasma HVA concentrations compared with healthy controls. Aim of this study is to elucidate whether HVA plasma levels in alcoholics are influenced by MTHFR C677T polymorphism. A total of 142 alcohol-dependent patients and 101 healthy controls were examined regarding plasma HVA concentration and MTHFR C677T genotype. Blood samples of alcoholics were obtained after a minimum of 22 days of abstinence. Among alcohol-dependent patients MTHFR C677T polymorphism was significantly associated with plasma HVA levels: carriers of MTHFR C677T T-allele had significantly lower HVA plasma levels compared with homozygote carriers of C-allele: 11.9 ng/ml versus 14.4 ng/ml (chi2: 5.39; P = 0.02). In healthy control subjects plasma HVA levels did not differ significantly between MTHFR C677T T-allele carriers and homozygote carriers of C-allele: 15.1 ng/ml versus 15.3 ng/ml (chi2: 0.04; P = 0.82). The data suggest an influence of MTHFR C677T polymorphism on plasma HVA among alcohol-dependent patients. This might be due to neurotoxic effects of homocysteine on the dopaminergic system or direct impairment of monoamine metabolism. Future studies should try to elucidate whether this effect is reversible during alcohol abstinence. PMID:17407503

  7. Association between dietary intake of folate, vitamin B6, B12 & MTHFR, MTR Genotype and breast cancer risk

    PubMed Central

    Weiwei, Zheng; Liping, Chen; Dequan, Li

    2014-01-01

    Objective: we conducted a case-control study to investigate the association between dietary folate, vitamin B6 and vitamin B12 intake, MTHFR and MTR genotype, and breast cancer risk. Methods: Genotyping for MTHFR C677T and A1298C and MTR A2756G polymorphisms were performed using polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) method. The intake of folate, vitamin B6 and vitamin B12 were calculated by each food item from questionnaire. Results: Subjects with breast cancer tended to have more first-degree relatives (?2=30.77, P<0.001) and have high intake of folate (t=2.42, P=0.008) and Vitamin B6 (t=2.94, P=0.002). Compared to the reference group, women with MTHFR 677 TT genotype and T allele had a significantly increased risk of breast cancer, with ORs (95%CI) of 1.8(1.08-2.27) and 1.39(1.02-1.92), respectively. For those who had folate intake?450 ug/day, MTHFR 667TT genotype was associated with a higher risk of breast cancer (OR=2.45, 95% CI=1.09-5.82, P=0.02). Similarly, subjects with Vitamin B6 intake?0.84 mg/day and MTHFR 667T allele genotype was correlated with a marginally increased risk of breast cancer. A significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer (P for interaction was 0.025). Conclusion: This case-control study found a significant association between MTHFR C667T polymorphism, folate intake and vitamin B6 and breast cancer risk, and a significant interaction was observed between MTHFR C667T polymorphism and folate intake on the risk of breast cancer. PMID:24639841

  8. Role of genetic mutations in folate-related enzyme genes on Male Infertility

    PubMed Central

    Liu, Kang; Zhao, Ruizhe; Shen, Min; Ye, Jiaxin; Li, Xiao; Huang, Yuan; Hua, Lixin; Wang, Zengjun; Li, Jie

    2015-01-01

    Several studies showed that the genetic mutations in the folate-related enzyme genes might be associated with male infertility; however, the results were still inconsistent. We performed a meta-analysis with trial sequential analysis to investigate the associations between the MTHFR C677T, MTHFR A1298C, MTR A2756G, MTRR A66G mutations and the MTHFR haplotype with the risk of male infertility. Overall, a total of 37 studies were selected. Our meta-analysis showed that the MTHFR C677T mutation was a risk factor for male infertility in both azoospermia and oligoasthenoteratozoospermia patients, especially in Asian population. Men carrying the MTHFR TC haplotype were most liable to suffer infertility while those with CC haplotype had lowest risk. On the other hand, the MTHFR A1298C mutation was not related to male infertility. MTR A2756G and MTRR A66G were potential candidates in the pathogenesis of male infertility, but more case-control studies were required to avoid false-positive outcomes. All of these results were confirmed by the trial sequential analysis. Finally, our meta-analysis with trial sequential analysis proved that the genetic mutations in the folate-related enzyme genes played a significant role in male infertility. PMID:26549413

  9. Role of genetic mutations in folate-related enzyme genes on Male Infertility.

    PubMed

    Liu, Kang; Zhao, Ruizhe; Shen, Min; Ye, Jiaxin; Li, Xiao; Huang, Yuan; Hua, Lixin; Wang, Zengjun; Li, Jie

    2015-01-01

    Several studies showed that the genetic mutations in the folate-related enzyme genes might be associated with male infertility; however, the results were still inconsistent. We performed a meta-analysis with trial sequential analysis to investigate the associations between the MTHFR C677T, MTHFR A1298C, MTR A2756G, MTRR A66G mutations and the MTHFR haplotype with the risk of male infertility. Overall, a total of 37 studies were selected. Our meta-analysis showed that the MTHFR C677T mutation was a risk factor for male infertility in both azoospermia and oligoasthenoteratozoospermia patients, especially in Asian population. Men carrying the MTHFR TC haplotype were most liable to suffer infertility while those with CC haplotype had lowest risk. On the other hand, the MTHFR A1298C mutation was not related to male infertility. MTR A2756G and MTRR A66G were potential candidates in the pathogenesis of male infertility, but more case-control studies were required to avoid false-positive outcomes. All of these results were confirmed by the trial sequential analysis. Finally, our meta-analysis with trial sequential analysis proved that the genetic mutations in the folate-related enzyme genes played a significant role in male infertility. PMID:26549413

  10. Polymorphisms of glutathione S-transferase and methylenetetrahydrofolate reductase genes in Moldavian patients with ulcerative colitis: Genotype-phenotype correlation

    PubMed Central

    Varzari, Alexander; Deyneko, Igor V.; Tudor, Elena; Turcan, Svetlana

    2015-01-01

    Background Glutathione S-transferases (GSTM1, GSTT1, and GSTP1) and methylenetetrahydrofolate reductase (MTHFR) are important enzymes for protection against oxidative stress. In addition, MTHFR has an essential role in DNA synthesis, repair, and methylation. Their polymorphisms have been implicated in the pathogenesis of ulcerative colitis (UC). The aim of the present study was to investigate the role of selected polymorphisms in these genes in the development of UC in the Moldavian population. Methods In a case-control study including 128 UC patients and 136 healthy individuals, GSTM1 and GSTT1 genotypes (polymorphic deletions) were determined using multiplex polymerase chain reaction (PCR). The GSTP1 rs1695 (Ile105Val), MTHFR rs1801133 (C677T), and MTHFR rs1801131 (A1298C) polymorphisms were studied with restriction fragment length polymorphism (RFLP) analysis. Genotype–phenotype correlations were examined using logistic regression analysis. Results None of the genotypes, either alone or in combination, showed a strong association with UC. The case-only sub-phenotypic association analysis showed an association of the MTHFR rs1801133 polymorphism with the extent of UC under co-dominant (p corrected = 0.040) and recessive (p corrected = 0.020; OR = 0.15; CI = 0.04–0.63) genetic models. Also, an association between the MTHFR rs1801131 polymorphism and the severity of UC was reported for the over-dominant model (p corrected = 0.023; coefficient = 0.32; 95% CI = 0.10–0.54). Conclusion The GST and MTHFR genotypes do not seem to be a relevant risk factor for UC in our sample. There was, however, evidence that variants in MTHFR may influence the clinical features in UC patients. Additional larger studies investigating the relationship between GST and MTHFR polymorphisms and UC are required. PMID:26862484

  11. Lack of association between MTHFR C677T polymorphism and breast cancer risk in Ahvaz, west south-Iran

    PubMed Central

    Mohammadzadeh, Ghorban; Karimi, Maryam; Bazyar, Mohammad; Hosseini, Seyed-Mohammad

    2016-01-01

    Background: Association between C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR), a key enzyme involved in folate metabolism and DNA methylation, and breast cancer risk are inconsistent. We investigated in a case-control study, possible effect of the common MTHFR C677T polymorphism on breast cancer risk in a sample of Iranian patients. Materials and Methods: The study subjects comprised of 123 breast cancer cases and 110 cancer-free control, who were matched for age and body mass index (BMI). C677T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Lipid profile was measured in all subjects by standard method. Results: The genotypes distributions (CC, CT, and TT) were 55.3, 39, and 5.7% in breast cancer cases and 51.8, 44.5, and 3.6% in controls. Chi square analysis revealed that there was no significant association between breast cancer risk and MTHFR genotypes and alleles. Additionally, no significant association was observed between C677T genotypes and biochemistry parameters. A multinomial logistic regression model with MTHFR genotypes, lipid profiles, BMI and age as covariates revealed that there is no significant association between MTHFR genotypes and risk of breast cancer, but higher values of LDL and HDL significantly increase risk of breast cancer. Conclusions: Our findings do not support the hypothesis that genetic variation in the MTHFR C677T polymorphism is implicated in the breast cancer risk in a sample of Iranian patients. PMID:27014653

  12. MTHFR C677T polymorphism is associated with hyperlipidemia in women with polycystic ovary syndrome

    PubMed Central

    Jain, Madhu; Pandey, Priyanka; Tiwary, Narendra K; Jain, Shuchi

    2012-01-01

    CONTEXT: Women with polycystic ovary syndrome (PCOS) are prone for coronary artery disease (CAD), and hyperhomocysteinemia is an independent risk factor for CAD. MTHFR deficiency is the most common cause of hyperhomocysteinemia, thereby provoking a possible association between PCOS and MTHFR C677T polymorphism. AIMS: The aim of this study was to investigate an association of MTHFR C677T polymorphism with PCOS. SETTINGS AND DESIGN: 92 women with PCOS (Rotterdam criteria) and 95 age-matched controls were compared with respect to MTHFR C677T polymorphism. The 2 genotypes (CC and CT) obtained were compared with clinical and laboratory parameters in women with PCOS. MATERIALS AND METHODS: In a case-control study, clinical, biochemical, hormonal and genetic analysis (PCR-RFLP of peripheral leucocytes) was carried out on all women with PCOS as well as controls. STATISTICAL ANALYSIS: Student “t” test for quantitative and Chi-square test for nominal variables was used. For estimation of risk, odds ratio and 95% confidence interval were calculated. RESULTS: The odds ratio of bearing a heterozygous genotype (CT) was 1.32 in women with PCOS as compared to controls (P = 0.48). No homozygous mutation (TT) was found in the study population. Serum cholesterol was more in heterozygous (CT) genotype (215.48 ± 25.56 mg/dl) as compared to normal (CC) genotype (203.29 ± 16.35 mg/dl) in women with PCOS (P = 0.01). Similarly, serum triglyceride was more in heterozygous (CT) genotype (95.86 ± 37.34 mg/dl) as compared to normal (CC) genotype (82.36 ± 20.88 mg/dl) in women with PCOS (P = 0.04). CONCLUSIONS: Although not statistically significant, there is a slightly higher prevalence of heterozygous (CT) genotype in women with PCOS. MTHFR C677T polymorphism when present may confer an increased susceptibility to develop hyperlipidemia in women with PCOS. More prospective studies are needed to confirm whether this hyperlipidemia due to MTHFR C677T polymorphism clinically manifests into CAD in long term in women with PCOS. PMID:22870016

  13. Predisposing factors and prevention of Clostridium perfringens-associated enteritis.

    PubMed

    Allaart, Janneke G; van Asten, Alphons J A M; Gröne, Andrea

    2013-09-01

    Clostridium perfringens is one of the major causes of intestinal disease in humans and animals. Its pathogenicity is contributed to by the production of a variety of toxins. In addition, predisposing environmental factors are important for the induction of C. perfringens-associated enteritis as shown by infection models. Environmental contamination, gastric and intestinal pH, intestinal microflora, nutrition, concurrent infections, and medical interventions may influence the intestinal colonization, growth, and toxin production by C. perfringens. Prevention of C. perfringens-associated enteritis may be mediated by the use of feed additives like probiotics, prebiotics, organic acids, essential oils, bacteriophages, lysozymes, bacteriocins, and antimicrobial peptides. Here we summarize and discuss published data on the influence of different environmental predisposing factors and preventive measures. Further research should focus on feed composition and feed additives in order to prevent C. perfringens-associated enteritis. PMID:23790636

  14. DNA methylation in schizophrenia subjects: gender and MTHFR 677C/T genotype differences

    PubMed Central

    Burghardt, Kyle J; Pilsner, J Richard; Bly, Michael J; Ellingrod, Vicki L

    2012-01-01

    Aim In schizophrenia, metabolic syndrome incidence is double that of the general population, with women having a higher incidence. Pharmacogenetically regulated folic acid may be related to this risk. DNA methylation and metabolic syndrome within this group has not been previously studied. Methods Metabolic syndrome was evaluated with fasting laboratory measurements, and dietary and lifestyle assessments. Methylation analysis used a peripheral sample for the LINE-1 assay. DNA was also genotyped for MTHFR 677C/T. Results This analysis included 133 subjects. We found a significant relationship between LINE-1 methylation, and an interaction between MTHFR and gender, controlling for serum folate (p = 0.008). Females with the 677TT genotype had the lowest methylation (56%) compared with the other groups (75%). Conclusion TT genotype females had the lowest methylation, which may explain metabolic syndrome gender differences in schizophrenia. Folate supplementation may be a suggested intervention within schizophrenia; however, additional work is required. PMID:22690662

  15. Development and Characterization of Reference Materials for MTHFR, SERPINA1, RET, BRCA1, and BRCA2 Genetic Testing

    PubMed Central

    Barker, Shannon D.; Bale, Sherri; Booker, Jessica; Buller, Arlene; Das, Soma; Friedman, Kenneth; Godwin, Andrew K.; Grody, Wayne W.; Highsmith, Edward; Kant, Jeffery A.; Lyon, Elaine; Mao, Rong; Monaghan, Kristin G.; Payne, Deborah A.; Pratt, Victoria M.; Schrijver, Iris; Shrimpton, Antony E.; Spector, Elaine; Telatar, Milhan; Toji, Lorraine; Weck, Karen; Zehnbauer, Barbara; Kalman, Lisa V.

    2009-01-01

    Well-characterized reference materials (RMs) are integral in maintaining clinical laboratory quality assurance for genetic testing. These RMs can be used for quality control, monitoring of test performance, test validation, and proficiency testing of DNA-based genetic tests. To address the need for such materials, the Centers for Disease Control and Prevention established the Genetic Testing Reference Material Coordination Program (GeT-RM), which works with the genetics community to improve public availability of characterized RMs for genetic testing. To date, the GeT-RM program has coordinated the characterization of publicly available genomic DNA RMs for a number of disorders, including cystic fibrosis, Huntington disease, fragile X, and several genetic conditions with relatively high prevalence in the Ashkenazi Jewish population. Genotypic information about a number of other cell lines has been collected and is also available. The present study includes the development and commutability/genotype characterization of 10 DNA samples for clinically relevant mutations or sequence variants in the following genes: MTHFR; SERPINA1; RET; BRCA1; and BRCA2. DNA samples were analyzed by 19 clinical genetic laboratories using a variety of assays and technology platforms. Concordance was 100% for all samples, with no differences observed between laboratories using different methods. All DNA samples are available from Coriell Cell Repositories and characterization information can be found on the GeT-RM website. PMID:19767587

  16. The MTHFR C677T Polymorphism and Risk of Intracerebral Hemorrhage in a Chinese Han Population

    PubMed Central

    Hu, Xin; Tao, Chuanyuan; Xie, Zhiyi; Li, Yunke; Zheng, Jun; Fang, Yuan; Lin, Sen; Li, Hao; You, Chao

    2016-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been speculated to be and extensively investigated as a risk factor for various vascular diseases, including intracerebral hemorrhage (ICH). However, results from published studies regarding the role of C677T polymorphism in ICH risk in Chinese populations were contradictory rather than conclusive. Material/Methods In this study, a total of 180 ICH patients and 180 matched controls of Chinese Han ethnicity were enrolled. The MTHFR C677T polymorphism was genotyped by polymerase chain reaction-ligation detection reaction (PCR-LDR). A meta-analysis was conducted by combining our data with previous relevant studies in Chinese populations. Results In our case-control study, similar allele frequency (p=0.492) and genotype distribution (p=0.748) of MTHFR C677T polymorphism were detected between ICH patients and controls. Further analysis based on hematoma location did not show a significant association. When combined with previous studies, however, C677T polymorphism was found to be significantly associated with an increased risk for ICH in Chinese populations (recessive model: OR=1.57, 95%CI=1.29–1.91). When focusing on the Han ethnicity, carriers of the TT genotype had an increased risk of ICH (recessive model: OR=1.36, 95%CI=1.05–1.75). Conclusions In this case-control study we did not observe that the MTHFR C677T polymorphism was associated with ICH risk in people of Chinese Han ethnicity. However, when combined with previous published studies, a significant association of C677T polymorphism with an increased risk of ICH was detected in Chinese populations, and also in the subgroup analysis focusing on Han ethnicity. PMID:26757363

  17. Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and promoter methylation in cervical oncogenic lesions and cancer

    PubMed Central

    Botezatu, Anca; Socolov, Demetra; Iancu, Iulia V; Huica, Irina; Plesa, Adriana; Ungureanu, Carmen; Anton, Gabriela

    2013-01-01

    The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using ? square test for the control group, the HPV-negative and HPV-positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV-positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high-risk (hr)HPV versus low-risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV. PMID:23444906

  18. The MTHFR C677T Polymorphism and Risk of Intracerebral Hemorrhage in a Chinese Han Population.

    PubMed

    Hu, Xin; Tao, Chuanyuan; Xie, Zhiyi; Li, Yunke; Zheng, Jun; Fang, Yuan; Lin, Sen; Li, Hao; You, Chao

    2016-01-01

    BACKGROUND Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been speculated to be and extensively investigated as a risk factor for various vascular diseases, including intracerebral hemorrhage (ICH). However, results from published studies regarding the role of C677T polymorphism in ICH risk in Chinese populations were contradictory rather than conclusive. MATERIAL AND METHODS In this study, a total of 180 ICH patients and 180 matched controls of Chinese Han ethnicity were enrolled. The MTHFR C677T polymorphism was genotyped by polymerase chain reaction-ligation detection reaction (PCR-LDR). A meta-analysis was conducted by combining our data with previous relevant studies in Chinese populations. RESULTS In our case-control study, similar allele frequency (p=0.492) and genotype distribution (p=0.748) of MTHFR C677T polymorphism were detected between ICH patients and controls. Further analysis based on hematoma location did not show a significant association. When combined with previous studies, however, C677T polymorphism was found to be significantly associated with an increased risk for ICH in Chinese populations (recessive model: OR=1.57, 95%CI=1.29-1.91). When focusing on the Han ethnicity, carriers of the TT genotype had an increased risk of ICH (recessive model: OR=1.36, 95%CI=1.05-1.75). CONCLUSIONS In this case-control study we did not observe that the MTHFR C677T polymorphism was associated with ICH risk in people of Chinese Han ethnicity. However, when combined with previous published studies, a significant association of C677T polymorphism with an increased risk of ICH was detected in Chinese populations, and also in the subgroup analysis focusing on Han ethnicity. PMID:26757363

  19. Meta-analysis of the association of MTHFR polymorphisms with multiple myeloma risk

    PubMed Central

    Ma, Li-Min; Ruan, Lin-Hai; Yang, Hai-Ping

    2015-01-01

    The association of methylenetetrahydrofolate reductase (MTHFR) polymorphisms with multiple myeloma (MM) risk has been explored, but the results remain controversial. Thus, a meta-analysis was performed to provide a comprehensively estimate. The case-control studies about MTHFR C677T and A1298C polymorphisms with MM risk were collected by searching PubMed, Elsevier, China National Knowledge Infrastructure and Wanfang Databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of association. Overall, no significant association was found between MTHFR A1298C polymorphism and MM risk under all four genetic models (AC vs. AA, OR?=?0.99, 95%CI?=?0.82-1.20; CC vs. AA, OR?=?1.14, 95%CI?=?0.77-1.68; recessive model, OR?=?1.10, 95%CI?=?0.76-1.59; dominant model, OR?=?1.01, 95%CI?=?0.84-1.22). The risk was also not significantly altered for C677T polymorphism and MM in overall comparisons (CT vs. CC, OR?=?1.04, 95%CI?=?0.93-1.17; TT vs. CC, OR?=?1.16, 95%CI?=?0.98-1.37; recessive model, OR?=?1.13, 95%CI?=?0.98-1.32; dominant model, OR?=?1.07, 95%CI?=?0.96-1.20). In subgroup analyses by ethnicity, no significant association was observed in both Caucasians and Asians. This meta-analysis suggested that MTHFR polymorphisms were not associated with MM risk. PMID:26022785

  20. Frequency of the MTHFR C677T polymorphism in Yemeni children with sickle cell disease.

    PubMed

    Al-Saqladi, Abdul-Wahab M; Harper, Greg; Delpisheh, Ali; Fijnvandraat, Karin; Bin-Gadeem, Hassan A; Brabin, Bernard J

    2010-01-01

    The frequency of the methylenetetrahydrofolate reductase enzyme (MTHFR) C677T mutation was determined using polymerase chain reaction (PCR) and with measurement of plasma total homocysteine (tHcy), folate, vitamins B6, B12 and disease severity in 102 SS children from Yemen. The homozygous TT genotype for MTHFR C677T was present in 2% (2/102), and heterozygous CT in 10.8% (11/102), giving an allele frequency of 7.35%. The T allele was not associated with raised plasma tHcy or increased disease severity. The mean [+/-SD (standard deviation)] tHcy was 2.8 +/- 1.7 micromol/L, increased with age and was highest in children >10 years (3.6 +/- 2.5 vs. 2.5 +/- 1.2 micromol/L, p <0.05). Whole blood folate and plasma vitamin B12 levels were normal or elevated, and 4% had vitamin B6 deficiency. In Yemeni children with sickle cell disease the frequency of the MTHFR C677T mutation was not higher than expected in the general population and was not associated with disease severity. PMID:20113291

  1. MTHFR C677T polymorphism interaction with heavy alcohol consumption increases head and neck carcinoma risk

    PubMed Central

    Zhuo, Xianlu; Song, Jue; Li, Dairong; Wu, Yongzhong; Zhou, Qi

    2015-01-01

    MTHFR C677T polymorphism has been indicated to be a risk factor for cancers, but its association with head and neck cancer (HNC) risk remains inconclusive. In the present study, we aimed to get a more precise estimation by performing a quantitative meta-analysis. Published papers up to Jun 2014 was searched and screened. Necessary information was rigorously extracted for data pooling and analyzing, and then, subgroup analyses on ethnicity, source of controls, sample size, tumor type, smoking and drinking status were also carried out. As a result, twenty-three case-control studies including 14298 subjects were included. The overall data failed to reveal a significant association between MTHFR C677T polymorphism and HNC risk (homozygote comparison model: OR?=?1.16; 95%CI?=?0.93-1.45; dominant model: OR?=?1.05; 95%CI?=?0.90-1.21; recessive model: OR?=?1.14; 95%CI?=?0.93-1.38). However, in the subgroup analysis about drinking status, increase risk was shown in the heavy drinking subgroup (TT vs CC: OR?=?3.11; 95%CI?=?1.52-3.02). In conclusion, the results of the present study suggest that Homozygous TT alleles of MTHFR C677T polymorphism might be a risk factor for HNC among individuals who have a heavy drinking history. Further studies are needed to get a more definitive conclusion. PMID:26035704

  2. Increasing the Number of SNP loci does not Necessarily Improve Prediction Power at Least in the Comparison of MTHFR SNP and Haplotypes

    PubMed Central

    Miyaki, Koichi; Takahashi, Yoshimitsu; Song, Yixuan; Zhang, Ling; Muramatsu, Masaaki; Nakayama, Takeo

    2008-01-01

    Background Rapid advances in genotyping technology have made it possible to easily utilize a large number of genetic markers. According to information theory, an increase in the number of markers provides more information; however, the clinical usefulness does not increase linearly. This study aimed to assess the effect of folic acid supplementation quantitatively in MTHFR haplotypes, and compare its prediction power with that of the C677T single nucleotide polymorphism (SNP) alone. Methods The study was a randomized, double-blind, placebo-controlled trial, designed in accordance with the CONSORT statement. The participants were 202 healthy Japanese males who were administered either folic acid at 1 mg/day or a placebo postoperatively for 3 months. The primary endpoint was the total plasma homocysteine levels (tHcy). Stratified analysis by HapMap-based tag SNPs was performed. Results Of 52 SNPs on the MTHFR gene, 4 SNP loci covering more than 80% of the information were selected, and the haplotypes were estimated. The haplotypes were classified into 3 groups (Hap0, Hap1, and Hap2), on the basis of the number of times the most frequent haplotype was present. The greatest decrease was observed in Hap2 (6.61 µmol/L), compared with the other haplotypes (Hap0, 2.67; Hap1, 2.60) (trend test, P < 0.01). The haplotype information obtained was not more informative than that obtained with grouping by a single SNP, C677T, which strongly influences enzyme activity. Conclusions Grouping by the C677T SNP alone was almost as good a predictor of the homocysteine-lowering effects as was grouping by the 4 best SNPs. This shows that increasing the number of typed SNPs does not necessarily provide more information, at least for this gene. A more efficient, cost-informative method for analyzing genomic data is required. PMID:19075497

  3. Infants' MTHFR polymorphisms and nonsyndromic orofacial clefts susceptibility: a meta-analysis based on 17 case-control studies.

    PubMed

    Pan, Yongchu; Zhang, Weibing; Ma, Junqing; Du, Yifei; Li, Dandan; Cai, Qi; Jiang, Hongbing; Wang, Meilin; Zhang, Zhengdong; Wang, Lin

    2012-09-01

    Methylenetetrahydrofolate reductase (MTHFR), an important enzyme in folate metabolism, is thought to be involved in the development of nonsyndromic orofacial clefts (NSOC). However, conflicting results have been achieved when evaluating the associations between infants' MTHFR C677T and A1298C polymorphisms and the risk of NSOC. To obtain more precise estimations of these associations, a meta-analysis recruiting 17 case-control studies was performed. Among Asians we found that CT heterozygote, TT homozygote, and CT/TT of infants' MTHFR C677T variant could contribute to elevated risks of NSOC, compared with CC wild-type homozygote (OR=1.741, 95% CI=1.043-2.907 for CT vs. CC, OR=2.311, 95% CI=1.313-4.041 for TT vs. CC, and OR=1.740, 95% CI=1.051-2.882 for CT/TT vs. CC, respectively). Similar effect was also observed on MTHFR 677T T allele, when using C allele as a reference in Asians (OR=1.420, 95% CI=1.191-1.693, for T allele vs. C allele). Furthermore, in stratified analysis by types of disease, CT/CC was suggested to confer decreased susceptibility to CL/P under recessive genetic model (OR=0.854, 95% CI=0.730-1.000). For MTHFR A1298C, the MTHFR 1298C allele in the case group of Caucasians was significantly lower than that in the control group, suggesting a protective effect against NSOC in Caucasian populations (OR=0.711, 95% CI=0.641-0.790, for C allele vs. A allele). In conclusion, the meta-analysis provided confirmative evidences that infants' MTHFR C677T and A1298C polymorphisms were involved in the development of NSOC. PMID:22847888

  4. MTHFR 677C/T and 1298A/C mutations and non-alcoholic fatty liver disease.

    PubMed

    Kasapoglu, Benan; Turkay, Cansel; Yalcin, Kadir Serkan; Kosar, Ali; Bozkurt, Alper

    2015-06-01

    Common genetic mutations encountered in folate metabolism may result in increased homocysteine (Hcy) levels. It has been reported that increased serum Hcy levels may affect the intracellular fat metabolism and may cause enhanced fatty infiltration in the liver resulting in non-alcoholic fatty liver disease (NAFLD). In total, 150 patients diagnosed with FLD by ultrasound examination and 136 healthy control patients that do not have any fatty infiltration in the liver were included in the study. Patients were grouped as mild (n = 88), moderate (n = 38) or severe (n = 24) according to the stage of fatty liver in ultrasound. Serum liver function tests, Hcy, folic acid and vitamin B12 levels of the patients were studied. The genetic MTHFR C677T and A1298C polymorphisms of the patients were also evaluated. Although there was no significant difference in vitamin B12 and folic acid levels, in the severe group, Hcy levels were significantly higher than that of control and mild groups (p<0.001). By contrast, there was no significant difference in heterozygote MTHFR 677C/T and 1298A/C mutations, both MTHFR 677C/T and MTHFR 1298A/C mutations were more common in NAFLD groups compared with the control patients (p<0.001). We have determined increased Hcy levels and increased prevalence of homozygote MTHFR 677C/T and MTHFR 1298A/C mutations in patients with NAFLD compared with healthy controls. Larger studies are warranted to clarify the etiological role of the MTHFR mutations and Hcy levels in FLD. PMID:26031974

  5. Celiac Disease in a Predisposed Subject (HLA-DQ2.5) with Coexisting Graves' Disease.

    PubMed

    Hwang, In Kyoung; Kim, Seon Hye; Lee, Unjoo; Chin, Sang Ouk; Rhee, Sang Youl; Oh, Seungjoon; Woo, Jeong Taek; Kim, Sung Woon; Kim, Young Seol; Chon, Suk

    2015-03-27

    Celiac disease is an intestinal autoimmune disorder, triggered by ingestion of a gluten-containing diet in genetically susceptible individuals. The genetic predisposition is related to human leukocyte antigen (HLA) class II genes, especially HLA-DQ2-positive patients. The prevalence of celiac disease has been estimated to be ~1% in Europe and the USA, but it is rarer and/or underdiagnosed in Asia. We report a case of celiac disease in a predisposed patient, with a HLA-DQ2 heterodimer, and Graves' disease that was treated successfully with a gluten-free diet. A 47-year-old woman complained of persistent chronic diarrhea and weight loss over a 9 month period. Results of all serological tests and stool exams were negative. However, the patient was found to carry the HLA DQ2 heterodimer. Symptoms improved after a gluten-free diet was initiated. The patient has been followed and has suffered no recurrence of symptoms while on the gluten-free diet. An overall diagnosis of celiac disease was made in a genetically predisposed patient (HLA-DQ2 heterodimer) with Graves' disease. PMID:25325278

  6. Massive pulmonary embolism associated with Factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase gene mutations in a young patient on oral contraceptive pills: a case report.

    PubMed

    Charafeddine, Khalil M; Mahfouz, Rami A; Ibrahim, Georges Y; Taher, Ali T; Hoballah, Jamal J; Taha, Assad M

    2010-10-01

    Factor V Leiden (Factor V G1691A), prothrombin gene mutation G20210A, and homozygous C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene are known to predispose venous thromboembolism (VTE). We present herein a rare case of a young woman heterozygous for these mutations and taking oral contraceptive pills for less than 2 months, diagnosed to have massive deep venous thrombosis and bilateral pulmonary embolism. The patient was managed for 10 days in the hospital and discharged home on oral anticoagulants. This case suggests that screening for these factors in people with family history of thrombosis and in relatives of patients with these mutations is highly recommended to prevent fatal consequences. In addition, a new guideline for treatment and prophylaxis with anticoagulant for these patients and others who are at risk of developing VTE (American College of Chest Physicians [ACCP] guidelines-Chest 2008) has been published recently. Our recommendation is to promote for the internationally published algorithms through their application, where necessary, to prevent any future thrombotic morbidity or mortality incidents. PMID:19520679

  7. Signaling pathway genes for blood pressure, folate and cholesterol levels among hypertensives: an epistasis analysis.

    PubMed

    Wei, L K; Menon, S; Griffiths, L R; Gan, S H

    2015-02-01

    Irregular atrial pressure, defective folate and cholesterol metabolism contribute to the pathogenesis of hypertension. However, little is known about the combined roles of the methylenetetrahydrofolate reductase (MTHFR), apolipoprotein-E (ApoE) and angiotensin-converting enzyme (ACE) genes, which are involved in metabolism and homeostasis. The objective of this study is to investigate the association of the MTHFR 677 C>T and 1298A>C, ACE insertion-deletion (I/D) and ApoE genetic polymorphisms with hypertension and to further explore the epistasis interactions that are involved in these mechanisms. A total of 594 subjects, including 348 normotensive and 246 hypertensive ischemic stroke subjects were recruited. The MTHFR 677 C>T and 1298A>C, ACE I/D and ApoEpolymorphisms were genotyped and the epistasis interaction were analyzed. The MTHFR 677 C>T and ApoE polymorphisms demonstrated significant associations with susceptibility to hypertension in multiple logistic regression models, multifactor dimensionality reduction and a classification and regression tree. In addition, the logistic regression model demonstrated that significant interactions between the ApoE E3E3, E2E4, E2E2 and MTHFR 677 C>T polymorphisms existed. In conclusion, the results of this epistasis study indicated significant association between the ApoE and MTHFR polymorphisms and hypertension. PMID:25055800

  8. [Pregnancy predispose to higher incidence of venous thromboembolism].

    PubMed

    Andersen, Anita Sylvest; Bergholt, Thomas; Salvig, Jannie Dalby; Hvas, Anne-Mette

    2015-11-30

    Venous thromboembolism (VTE) is a major cause of maternal morbidity and mortality despite the possibility to prevent and treat the disorder. The hypercoagulability of normal pregnancy predispose to an approximately six-fold higher incidence of VTE in pregnancy. Identification of risk pregnancies and start of prophylaxis is essential, as is early diagnosis of VTE to prevent progression and pulmonary embolism. For anticoagulant treatment and prophylaxis in pregnancy, low molecular weight heparin is the drug of choice and prophylaxis, if indicated, should initiate as soon as pregnancy is confirmed. PMID:26651557

  9. The role of the polymorphic genes apolipoprotein E and methylene- tetrahydrofolate reductase in the development of dementia of the Alzheimer type.

    PubMed

    Regland, B; Blennow, K; Germgård, T; Koch-Schmidt, A C; Gottfries, C G

    1999-01-01

    The gene for apolipoprotein E (APOE) is polymorphic, and its variant APOE4 is a major risk factor for the development of Alzheimer-type dementia (AD). Another risk factor for AD appears to be negative cobalamin balance, which is very common in elderly people. Cobalamin and folate are interdependent and essential components of the one-carbon metabolism. Another important component is methylenetetrahydrofolate reductase (MTHFR), the gene for which is also polymorphic. Thermolabile MTHFR (tMTHFR), a gene variant that reduces the activity of its enzyme, is common in the general population. In the present study, 75% of 140 AD patients had at least one APOE4 allele. The numbers of APOE4 and tMTHFR alleles correlated significantly with the serum folate levels, however, in opposite directions. The significance of this was augmented by an inverse correlation between APOE4 and tMTHFR. Thus, not only MTHFR but also APOE appears to be related to the one-carbon metabolism, suggesting that APOE4 and insufficient one-carbon metabolism may be synergistic risk factors for AD. PMID:10364640

  10. The maize brown midrib2 (bm2) gene encodes a methylenetetrahydrofolate reductase that contributes to lignin accumulation

    PubMed Central

    Tang, Ho Man; Liu, Sanzhen; Hill-Skinner, Sarah; Wu, Wei; Reed, Danielle; Yeh, Cheng-Ting; Nettleton, Dan; Schnable, Patrick S

    2014-01-01

    The midribs of maize brown midrib (bm) mutants exhibit a reddish-brown color associated with reductions in lignin concentration and alterations in lignin composition. Here, we report the mapping, cloning, and functional and biochemical analyses of the bm2 gene. The bm2 gene was mapped to a small region of chromosome 1 that contains a putative methylenetetrahydrofolate reductase (MTHFR) gene, which is down-regulated in bm2 mutant plants. Analyses of multiple Mu-induced bm2-Mu mutant alleles confirmed that this constitutively expressed gene is bm2. Yeast complementation experiments and a previously published biochemical characterization show that the bm2 gene encodes a functional MTHFR. Quantitative RT-PCR analyses demonstrated that the bm2 mutants accumulate substantially reduced levels of bm2 transcript. Alteration of MTHFR function is expected to influence accumulation of the methyl donor S-adenosyl-l-methionine (SAM). Because SAM is consumed by two methyltransferases in the lignin pathway (Ye et al., 1994), the finding that bm2 encodes a functional MTHFR is consistent with its lignin phenotype. Consistent with this functional assignment of bm2, the expression patterns of genes in a variety of SAM-dependent or -related pathways, including lignin biosynthesis, are altered in the bm2 mutant. Biochemical assays confirmed that bm2 mutants accumulate reduced levels of lignin with altered composition compared to wild-type. Hence, this study demonstrates a role for MTHFR in lignin biosynthesis. PMID:24286468

  11. Predisposing factors in degenerative spondylolisthesis. A radiographic and CT study.

    PubMed

    Cinotti, G; Postacchini, F; Fassari, F; Urso, S

    1997-01-01

    We report a prospective study analysing whether possible factors predisposing to degenerative spondylolisthesis (DS) must be present concomitantly in order to cause vertebral slipping. Standard and flexion-extension radiographs were obtained from 27 patients with DS and 27 without spondylolisthesis. The level of the intercrestal line, the lumbosacral angle, the presence of sacralization of L5 and vertebral motion at the L4-L5 level were assessed. Facet joint orientations were measured on CT scans. Only facet joint orientation and vertebral motion at the spondylolisthetic level were significantly different in patients with DS compared with controls. Facet joints were oriented more sagittally both at the spondylolisthetic level and at the levels above and below. An inverse linear correlation was found between the sagittal orientation of facet joints and the mobility of the slipped vertebra. Abnormal sagittal orientation of facet joints and hypermobility of the spondylolisthetic vertebra appear to play major roles among possible factors predisposing to DS. Both factors should be considered in the planning of surgical treatment. PMID:9476166

  12. Methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and G1793A genotypes, and the relationship between maternal folate intake, tibia lead and infant size at birth

    PubMed Central

    Kordas, Katarzyna; Ettinger, Adrienne S.; Lamadrid-Figueroa, Héctor; Tellez-Rojo, Martha M.; Hérnandez-Avila, Mauricio; Hu, Howard; Wright, Robert O.

    2011-01-01

    Small size at birth continues to be a problem worldwide and many factors, including reduced folate intake and Pb exposure, are associated with it. However, single factors rarely explain the variability in birth weight, suggesting a need for more complex explanatory models. We investigated environment–gene interactions to understand whether folate intake and maternal Pb exposure were associated with smaller newborn size in 474 women with uncomplicated pregnancies delivering term infants in Mexico City. We examined if folate intake modified the negative effects of maternal Pb burden on birth size. We also asked if maternal and infant methylenetetrahydrofolate reductase (MTHFR) genotypes (C677T, A1298C and G1793A) modified the effects of folate intake or Pb exposure on birth size. Women were aged 24·6 (SD 5·1) years; 43·5 % were primiparous. Maternal blood Pb at delivery was 86 (SD 42) ?g/l, with 26·7 % having levels ?100 ?g/l. Tibia Pb level was 9·9 (SD 9·8) ?g/g. Of the women, 35·3 % had folate intakes <400 ?g/d. Birth weight was 3170 (SD 422) g. In covariate-adjusted regressions, higher folate intake was associated with higher birth weight (? 0·04; P<0·05). Higher bone Pb was associated with lower birth weight (? ?4·9; P<0·05). Folate intake did not modify the effects of Pb on birth size, nor did MTHFR modify the association between Pb or folate intake on birth size. Although modest, the relationship between maternal nutrition, Pb burden and birth size does underscore the importance of environmental exposures to child health because patterns of fetal growth may affect health outcomes well into adulthood. PMID:19338708

  13. High-dose folic acid supplementation alters the human sperm methylome and is influenced by the MTHFR C677T polymorphism.

    PubMed

    Aarabi, Mahmoud; San Gabriel, Maria C; Chan, Donovan; Behan, Nathalie A; Caron, Maxime; Pastinen, Tomi; Bourque, Guillaume; MacFarlane, Amanda J; Zini, Armand; Trasler, Jacquetta

    2015-11-15

    Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodeled during spermatogenesis. While high-dose folic acid supplementation (up to 10 times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementation on the sperm epigenome are unknown. To assess the impact of 6 months of high-dose folic acid supplementation on the sperm epigenome, we studied 30 men with idiopathic infertility. Blood folate concentrations increased significantly after supplementation with no significant improvements in sperm parameters. Methylation levels of the differentially methylated regions of several imprinted loci (H19, DLK1/GTL2, MEST, SNRPN, PLAGL1, KCNQ1OT1) were normal both before and after supplementation. Reduced representation bisulfite sequencing (RRBS) revealed a significant global loss of methylation across different regions of the sperm genome. The most marked loss of DNA methylation was found in sperm from patients homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, a common polymorphism in a key enzyme required for folate metabolism. RRBS analysis also showed that most of the differentially methylated tiles were located in DNA repeats, low CpG-density and intergenic regions. Ingenuity Pathway Analysis revealed that methylation of promoter regions was altered in several genes involved in cancer and neurobehavioral disorders including CBFA2T3, PTPN6, COL18A1, ALDH2, UBE4B, ERBB2, GABRB3, CNTNAP4 and NIPA1. Our data reveal alterations of the human sperm epigenome associated with high-dose folic acid supplementation, effects that were exacerbated by a common polymorphism in MTHFR. PMID:26307085

  14. Prevalence of factor V Leiden, prothrombin G20210A, and MTHFR C677T mutations in 200 healthy Jordanians.

    PubMed

    Eid, Suhair S; Rihani, Ghada

    2004-01-01

    Thrombophilia is now considered a multi-causal condition, with interplay of acquired genetic risk factors. In order to estimate the frequency of the factor V Leiden, prothrombin G20210A, and MTHFR C677T mutations in the Jordanian population, we screened 200 healthy Jordanian individuals. 40% were females. Mean age was 32.1 years for males and 30.0 years for female participants. A PCR method detected 15.0% factor V Leiden (87% heterozygous, 13% homozygous), 2% prothrombin G20210A (100% heterozygous), and 24% MTHFR C677T (67% heterozygous, 33% homozygous). We conclude that the prevalence of factor V Leiden and MTHFR C677T is elevated in this population of Jordanians. However the incidence of G20210A is relatively low. Quantification of these genetic thrombosis risk factors in various populations will contribute to a better understanding of the interaction of genetic and environmental risk factors. PMID:15559724

  15. Multiloculated hydrocephalus of intrauterine-onset: a case report of an unexpected MTHFR A1298C positive test result.

    PubMed

    Cizmeci, M N; Akelma, A Z; Kosehan, D; Kutukoglu, I; Sonmez, F M

    2013-01-01

    Loculated hydrocephalus is a condition in which discrete fluid-filled compartments form in association with the ventricular system of the brain. Multiloculated hydrocephalus is a subgroup of this entity involving more than one segment of the ventricular system. Abnormal descent of the cerebellar components can cause multiloculated hydrocephalus due to various pathogenesis. However, studies report no more than 10% of correlation between cerebellar herniation and hydrocephalus. We report an infant with MTHFR A1298C homozygosity, who had hydrocephalus of intrauterine-onset. Alterations in the folate metabolism might lead to congenital hydrocephalus and there is growing data on the prothrombotic effects of MTHFR polymorphisms. To the best of our knowledge, there has been no reported case of MTHFR A1298C homozygosity and intrauterine-onset multiloculated hydrocephalus as a co-existence in the literature. PMID:24341140

  16. TPMT and MTHFR Genotype is not Associated With Altered Risk of Thioguanine-Related Sinusoidal Obstruction Syndrome in Pediatric Acute Lymphoblastic Leukemia: A Report from the Children’s Oncology Group

    PubMed Central

    Wray, Lisa; Vujkovic, Marijana; McWilliams, Thomas; Cannon, Shannon; Devidas, Meenakshi; Stork, Linda; Aplenc, Richard

    2014-01-01

    Sinusoidal obstruction syndrome is a complication of therapy for pediatric ALL and may be modified by thiopurine methyltransferase activity as well as by MTHFR genotype. We assessed TPMT * 3A, * 3B, * 3C, and MTHFR C677T and A1298C germline genetic polymorphisms among 351 patients enrolled in the thioguanine treatment arm of CCG-1952 clinical trial. TPMT and MTHFR C677T genotypes were not associated with SOS risk. The combination of MTHFR and TPMT variant genotypes was not associated with SOS risk. These suggest that germline genetic variation in TPMT and MTHFR do not significantly alter SOS risk in patients exposed to thioguanine. PMID:24737678

  17. Adaptive developmental plasticity in methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism limits its frequency in South Indians.

    PubMed

    Naushad, Shaik Mohammad; Krishnaprasad, Chintakindi; Devi, Akella Radha Rama

    2014-05-01

    Methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism shows considerable heterogeneity in its distribution in humans worldwide. The current study was conducted to investigate whether this polymorphism exhibited adaptive developmental plasticity in the control of the TT-genotype frequency. We screened 1,818 South Indian subjects (895 males and 923 females) for MTHFR C677T polymorphism using PCR-restriction fragment length polymorphism approach. MTHFR 677T-allele frequency in males and females was 9.1 and 11.0%, respectively. Compared to females, males had lower frequency of TT-genotype [odds ratio 0.31, 95% confidence interval (CI) 0.08-1.01]. The frequency of MTHFR 677T-allele was highest in the age group of 20-40 years and it gradually decreased from 40-60 to 60-80 years (P trend<0.0001). MTHFR 677TT-genotype was associated with 7.02-folds (95% CI: 2.12-25.63, P<0.0001) cumulative risk for recurrent pregnancy loss (RPL), neural tube defects (NTDs) and deep vein thrombosis (DVT). Linear regression model suggested that male gender exhibited increased homocysteine levels by 9.35 ?mol/L while each MTHFR 677T-allele contributed to 4.63 ?mol/L increase in homocysteine. Plasma homocysteine showed inverse correlation with dietary folate (r=-0.17, P<0.0001), B2 (r=-0.14, P<0.0001) and B6 (r=-0.07, P=0.03). Examination of the spontaneously aborted fetuses (n=35) showed no significant association of fetal genotype on its in utero viability. From the current study, it was concluded that C677T seemed to have acquired adaptive developmental plasticity among South Indians due to environmental influences thus contributing to hyperhomocysteinemia and its associated complications such as RPL, NTDs, DVT, etc. PMID:24449370

  18. Population distribution of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C risk alleles for methotrexate toxicity in Israel.

    PubMed

    Efrati, Edna; Elkin, Hela; Nahum, Sagi; Krivoy, Norberto

    2013-04-01

    Methylenetetrahydrofolate reductase (MTHFR) is a central regulatory enzyme in the folate pathway. Two non-synonymous single nucleotide polymorphisms in MTHFR, C677T (rs1801133) and A1298C (rs1801131) have been associated with reduced MTHFR enzyme activity. These polymorphisms, especially C677T, appear to be linked with methotrexate-related toxicity, particularly hepatotoxicity; thus, pretreatment identification of individuals carrying these polymorphisms may be of clinical relevance. The purpose of this study was to determine the frequency and distribution of MTHFR polymorphic variants, known to functionally impair MTHFR activity, in the highly heterogeneous Israeli population. MTHFR genotyping was carried out in the representatives of three major demographic groups in Israel by PCR-restriction fragment length polymorphism and high-resolution melting. The relative distribution of variant alleles 677T and 1298C was found to be similar in individuals of Jewish, Druze and Arab Moslem descent (p = 0.09). However, Ashkenazi Jews displayed a 1.9-fold higher frequency of variant 677T and a 1.8-fold lower frequency of variant 1298C compared to non-Ashkenazi Jews (p < 0.001). Distinct differences in the relative frequencies of both polymorphisms were also found between Ashkenazi Jews and Druze (p < 0.01 for C677T, p < 0.01 for A1298C) or Ashkenazi Jews and Arab Moslem (p < 0.01 for C677T, p < 0.05 for A1298C). These data underscore the importance of geographic genetic analysis for a better understanding of human pharmacotherapy and personalized medicine. PMID:22847291

  19. Interaction of MTHFR 1298C with ACE D allele augments the risk of diabetic nephropathy in Western Iran.

    PubMed

    Rahimi, Zohreh; Hasanvand, Ali; Felehgari, Vahid

    2012-04-01

    The aim of the current study was to examine the influence of interaction between polymorphisms of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C with angiotensin converting enzyme insertion/deletion (ACE I/D) polymorphism on the risk of diabetic nephropathy (DN). In a case control study using polymerase chain reaction (PCR)- and PCR-restriction fragment length polymorphism (RFLP), the presence of three polymorphisms in 140 patients with type 2 diabetes mellitus (T2DM) with nephropathy including patients with micro- and macro-albuminuria and 72 patients with normoalbuminuria from Western Iran were investigated. In the presence of both MTHFR 677 T and ACE D alleles, there was a trend toward increased risk of DN 2.68-fold (p=0.054). The possession of both MTHFR 677 T and ACE D alleles increased the risk of macro-albuminuria four times (p=0.035). The concomitant presence of both MTHFR 1298 C and ACE D alleles increased the risk of macro-albuminuria 7.8-fold (p=0.012). In addition, the risk of progression from micro- to macro-albuminuria in the presence of both alleles tended to be increased (4.1-fold, p=0.09). Our study for the first time demonstrated a synergistic effect between ACE I/D with either MTHFR C677T or A1298C polymorphism on the increased risk of DN among patients with T2DM. We found that MTHFR 1298 C strongly interacts with the ACE D allele and augments the risk of DN in our population. PMID:21942443

  20. Polymorphisms of MTHFR C677T and A1298C association with oral carcinoma risk: a meta-analysis.

    PubMed

    Zhuo, Xianlu; Ling, Junjun; Zhou, Yan; Zhao, Houyu; Song, Yufeng; Tan, Yinghui

    2012-07-01

    Investigations regarding association of MTHFR polymorphisms with oral carcinoma risk have yielded inconclusive results. Thus, meta-analyses were performed. Results showed that no associations of C677T polymorphisms with oral carcinoma were observed for the overall data. In subgroup analyses by drinking status, homozygous TT alleles exhibited elevated oral cancer susceptibility in heavy drinkers. For A1298C polymorphism, CC alleles presented a possible preventive role for oral cancer. Collectively, results suggest that MTHFR 677TT polymorphism might be a low-penetrant risk factor for oral carcinoma only in heavy drinkers. Conversely, 1298CC alleles might play a preventive role for oral cancer. PMID:22536935

  1. Serum Folate and Methylenetetrahydrofolate Reductase (MTHFR) C677T Polymorphism Adjusted for Folate Intake

    PubMed Central

    Nishio, Kazuko; Goto, Yasuyuki; Kondo, Takaaki; Ito, Shimon; Ishida, Yoshiko; Kawai, Sayo; Naito, Mariko; Wakai, Kenji; Hamajima, Nobuyuki

    2008-01-01

    Background Serum folate concentration is lower in individuals with the methylenetetrahydrofolate reductase (MTHFR) 677TT genotype than in those with the MTHFR 677CC or 677CT genotypes. Since studies considering folate intake are limited, we examined the association between folate intake and serum folate levels, according to the genotype. Methods The subjects comprised 170 Japanese persons (74 males and 96 females) aged 20-75 years who visited a clinic to test for Helicobacter pylori infection. Folate intake was estimated using a semiquantitative food-frequency questionnaire, and serum folate was measured in the residual fasting blood samples of the subjects. MTHFR C677T was genotyped using polymerase chain reaction. Results The geometric means of serum folate level were 6.19, 6.20, and 5.17 ng/mL among the 60 participants with the 677CC genotype, 90 participants with the 677CT genotype, and 20 participants with the 677TT genotype, respectively. No difference was noted in the mean folate intake estimated using the food-frequency questionnaire. Regression analysis showed that loge(serum folate) adjusted for age, sex, and loge(folate intake) was significantly lower among those with the 677TT genotype than among those with the 677CT or 677CC genotypes (p = 0.01). The adjusted reduction in serum folate was 20.2% (95% confidence interval, 5.4-32.6%) in the case of the 677TT genotype relative to the levels in the case of the 677CC/677CT genotypes. When folate intake was adjusted for total energy intake, using the residual method, the slope of the regression line for 677TT was smaller than those of the regression lines for 677CC and 677CT. Conclusion Individuals with the 677TT genotype may need to consume more folate to maintain serum folate levels similar to those found in individuals with the 677CC/677CT genotypes. PMID:18480590

  2. MTHFR polymorphic variant C677T is associated to vascular complications in sickle-cell disease.

    PubMed

    Hatzlhofer, Betânia L D; Bezerra, Marcos André C; Santos, Magnun N N; Albuquerque, Dulcinéia M; Freitas, Elizabete M; Costa, Fernando F; Araújo, Aderson S; Muniz, Maria Tereza C

    2012-09-01

    Vaso-occlusion is a determinant for most signs and symptoms of sickle-cell anemia (SCA). The mechanisms involved in the pathogenesis of vascular complications in SCA remain unclear. It is known that genetic polymorphisms associated with thrombophilia may be potential modifiers of clinical features of SCA. The genetic polymorphisms C677T and A1298C relating to the enzyme methylenetetrahydrofolate reductase (MTHFR), a clotting Factor V Leiden mutation (1691G?A substitution of Factor V Leiden), and the mutant prothrombin 20210A allele were analyzed in this study. The aim was to find possible correlations with vascular complications and thrombophilia markers in a group of SCA patients in Pernambuco, Brazil. The study included 277 SCA patients, divided into two groups: one consisting of 177 nonconsanguineous SCA patients who presented vascular manifestations of stroke, avascular necrosis, leg ulcers, priapism, and acute chest syndrome (group 1); and the other consisting of 100 SCA patients without any reported vascular complication (group 2). Molecular tests were done using either polymerase chain reaction (PCR) restriction fragment length polymorphism or allele-specific PCR techniques. Comparisons between the groups were made using the ?(2) test. The 677 CT and TT genotypes showed a significant risk of vascular complications (p=0.015). No significant associations between the groups were found when samples were analyzed for the MTHFR A1298C allele (p=0.913), Factor V G1691 (p=0.555), or prothrombin G20210A mutation (p=1.000). The polymorphism MTHFR C677T seemed to be possibly predictive for the development of some vascular complications in SCA patients among this population. PMID:22924497

  3. Subclinical Mastitis in Dairy Animals: Incidence, Economics, and Predisposing Factors

    PubMed Central

    Sinha, Mukesh Kr.; Thombare, N. N.; Mondal, Biswajit

    2014-01-01

    A study was conducted to assess the incidence and economics of subclinical form of bovine mastitis in Central Region of India. Daily milk records of 187 animals during three seasons were collected and subjected to analysis. The economic loss due to reduction in yield, clinical expenses, and additional resources used were quantified and aggregated. The losses due to mastitis in monetary terms were estimated to be INR1390 per lactation, among which around 49% was owing to loss of value from milk and 37% on account of veterinary expenses. Higher losses were observed in crossbred cows due to their high production potential that was affected during mastitis period. The cost of treating an animal was estimated to be INR509 which includes cost of medicine (31.10%) and services (5.47%). Inadequate sanitation, hygiene, and veterinary services were the main predisposing factors for incidence and spread of mastitis as perceived by the respondents. PMID:25093203

  4. A case of vascular parkinsonism associated with hyperhomocysteinemia and methylenetetrahydrofolate reductase gene variant (C677T).

    PubMed

    Hara, Kenju; Onda, Keigo; Ouchi, Haruka; Shibano, Ken; Ishiguro, Hideaki

    2016-03-01

    A 56-year-old man, who presented with 6 years history of difficulty in walking, was diagnosed as having vascular parkinsonism on the basis of the clinical findings of parkinsonism, pyramidal sign and the brain MRI findings of multiple lacunar infarction. Although he did not have hypertension, he had hyperhomocysteinemia and homozygous methylenetetrahydrofolate reductase (MTHFR) gene variant (C677T) as risk factors for ischemic stroke. Recent studies have shown that hyperhomocysteinemia and MTHFR gene variant are associated with small-vessel disease, suggesting that these risk factors may underlie vascular parkinsonism, particularly in patients lacking hypertension and in those with a relatively younger age at onset of this disease. PMID:26797478

  5. The JAK2 46/1 haplotype does not predispose to CALR-mutated myeloproliferative neoplasms.

    PubMed

    Soler, G; Bernal-Vicente, A; Antón, A I; Torregrosa, J M; Caparrós-Pérez, E; Sánchez-Serrano, I; Martínez-Pérez, A; Sánchez-Vega, B; Vicente, V; Ferrer-Marin, F

    2015-05-01

    Somatic mutations in the CALR gene were recently discovered in a substantial proportion of Philadelphia-negative chronic myeloproliferative neoplasm (cMPN) patients lacking JAK2 and MPL mutations. Somatically acquired defects are not the only pathogenic mechanism involved in these disorders. Since germline JAK2 46/1 haplotype predisposes to cMPN-associated mutations, including JAK2V617F and MPLW515K7L, we evaluated whether the 46/1 haplotype also confers susceptibility to CALR-mutated cMPN, both in sporadic and familial cases. The single-nucleotide polymorphism rs10974944, which tags 46/1, was investigated in 155 sporadic MPN patients and 270 unrelated controls, as well as in 11 familial cMPN cases and 36 unaffected relative controls. As described elsewhere, the 46/1 haplotype was overrepresented, both in sporadic and familial cMPN. In sporadic cMPN, the JAK2 46/1 haplotype was closely associated with JAK2V617F (p?=?0.0003) but not with JAK2-nonmutated cases. Analysis of CALR-mutated sporadic cMPN (n?=?22) showed no association between CALR mutations and 46/1 haplotype (p?=?0.87). Regarding the familial cMPN, the prevalence of carriers of the G allele was higher in familial (81.8%) than in sporadic (62%) cMPN, but it did not differ significantly (p?=?0.3). Although we described a family with carriers of both JAK2V617F and CALR mutations, due to the low number of CALR-mutated familial cases, we could not determinate whether the JAK2 46/1 haplotype predisposes or does not to CALR-mutated familial cMPN. We conclude, for the first time, that the 46/1 haplotype, unlike JAK2V617F and MPLW515K7L, is not associated with CALR-mutated cMPN. PMID:25482455

  6. The prevalence of folate-remedial MTHFR enzyme variants in humans

    PubMed Central

    Marini, Nicholas J.; Gin, Jennifer; Ziegle, Janet; Keho, Kathryn Hunkapiller; Ginzinger, David; Gilbert, Dennis A.; Rine, Jasper

    2008-01-01

    Studies of rare, inborn metabolic diseases establish that the phenotypes of some mutations in vitamin-dependent enzymes can be suppressed by supplementation of the cognate vitamin, which restores function of the defective enzyme. To determine whether polymorphisms exist that more subtly affect enzymes yet are augmentable in the same way, we sequenced the coding region of a prototypical vitamin-dependent enzyme, methylenetetrahydrofolate reductase (MTHFR), from 564 individuals of diverse ethnicities. All nonsynonymous changes were evaluated in functional in vivo assays in Saccharomyces cerevisiae to identify enzymatic defects and folate remediability of impaired alleles. We identified 14 nonsynonymous changes: 11 alleles with minor allele frequencies <1% and 3 common alleles (A222V, E429A, and R594Q). Four of 11 low-frequency alleles affected enzyme function, as did A222V. Of the five impaired alleles, four could be restored to normal functionality by elevating intracellular folate levels. All five impaired alleles mapped to the N-terminal catalytic domain of the enzyme, whereas changes in the C-terminal regulatory domain had little effect on activity. Impaired activity correlated with the phosphorylation state of MTHFR, with more severe mutations resulting in lower abundance of the phosphorylated protein. Significantly, diploid yeast heterozygous for mutant alleles were impaired for growth, particularly with lower folate supplementation. These results suggested that multiple less-frequent alleles, in aggregate, might significantly contribute to metabolic dysfunction. Furthermore, vitamin remediation of mutant enzymes may be a common phenomenon in certain domains of proteins. PMID:18523009

  7. [Population study of frequency of methylenetetrahydrofolate reductase C677T gene polymorphism in Yakutia].

    PubMed

    Spiridonova, M G; Stepanov, V A; Maksimova, N R; Puzyrev, V P

    2004-05-01

    The enzyme methylenetetrahydrofolate reductase (MTHFR) catalyzes synthesis of 5'-methylenehydrofolate, which is the methyl donor for the conversion of homocysteine to methionine. According to the numerous literature data, polymorphic variant of the MTHFR-encoding gene, C677T, is associated with hyperhomocysteinemia, vascular pathologies, neural tube defects, dementia, perinatal mortality, mental disorders, long-term neurodegenerative disorders, lens displacement, arachnodactyly, and venous thromboses. The present study was focused on the analysis of the C677T polymorphism (missence mutation leading to the replacement of cytosine by thymine at position 677) of the MTHFR gene in three indigenous populations of the Republic of Sakha (Yakutia), living in the settlements of Cheriktei, Byadi, and Dyupsya. Comparison of the genotype and allele frequencies revealed no substantial differences between the three Yakut populations, as well as between Yakuts and other Mongoloid ethnic groups. PMID:15272569

  8. Association of deep venous thrombosis with prothrombotic gene polymorphism identified in lung cancer cases.

    PubMed

    Arslan, Sulhattin; Manduz, Sinasi; Epöztürk, Kür?at; Karahan, O?uz; Akkurt, Ibrahim

    2011-04-01

    Venous thrombosis is a significant cause of morbidity and mortality in patients with malignancies. We aimed to investigate the association between prothrombotic gene polymorphisms detected in lung cancer cases and deep venous thrombosis (DVT). Totally 66 patients with an established diagnosis of lung cancer, of which 33 developed DVT, were enrolled. Multiplex PCR technique and reverse hybridization strip assay were performed on DNA extracted from peripheral blood, in order to analyze prothrombin G20210A, factor V G1691A, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE), plasminogen activator inhibitor-1 (PAI-1), and glycoprotein IIIa (Gp IIIa) gene mutations. Among prothrombotic gene polymorphisms investigated in this study, the commonest ones were PAI-1 4G/5G (56% heterozygous, 39% homozygous) and ACE gene mutations (58% heterozygous, 17% homozygous). The presence of homozygous MTHFR A1298C mutation was significantly associated with DVT (P=0.020). Comparing the lung cancer patients with and without DVT, only MTHFR A1298C gene polymorphism differed significantly (P=0.040). We determined a higher rate of prothrombotic gene mutations in lung cancer patients who developed DVT. However, statistical significance was achieved only for MTHFR A1298C gene mutation. Therefore, nongenetic factors for disturbance of hemostatic metabolism should also be considered in lung cancer patients. PMID:21080081

  9. The MTHFR 677T Allele May Influence the Severity and Biochemical Risk Factors of Alzheimer's Disease in an Egyptian Population

    PubMed Central

    Elhawary, Nasser Attia; Hewedi, Doaa; Arab, Arwa; Teama, Salwa; Tayeb, Mohammed Taher; Bogari, Neda

    2013-01-01

    Objective. We evaluated whether the methylenetetrahydrofolate reductase (MTHFR) 677C>T marker influences the risk and severity of Alzheimer's disease (AD) and whether AD is associated with homocysteine, vitamin B12, and cholesterol levels in Egypt. Methods. Forty-three Alzheimer's cases and 32 non-AD controls were genotyped for the 677C>T polymorphism. Clinical characteristics and levels of homocysteine, vitamin B12, and cholesterol were assessed. Results. No significant differences in the frequencies of the MTHFR alleles or genotypes between AD cases and controls (P = 0.14) were identified. The 677T mutant allele was significantly overrepresented in AD cases compared to controls (OR = 2.22; P = 0.03). The 677T/T frequency was three times higher in AD patients than in controls, which could increase plasma homocysteine levels. Severe cases of AD were the most frequent in patients with the T/T genotype (11.6%). The effect of the MTHFR polymorphism on the risk of AD may be independent of homocysteine, vitamin B12, or even cholesterol levels. Conclusions. The MTHFR 677C>T polymorphism—especially the presence of one copy of the T allele—appears to confer a potential risk for the development of AD. The T/T genotype may contribute to hypercysteinemia as a sensitive marker. PMID:24223459

  10. Microarray-based detection of CYP1A1, CYP2C9, CYP2C19, CYP2D6, GSTT1, GSTM1, MTHFR, MTRR, NQO1, NAT2, HLA-DQA1, and AB0 allele frequencies in native Russians.

    PubMed

    Gra, Olga; Mityaeva, Olga; Berdichevets, Iryna; Kozhekbaeva, Zhanna; Fesenko, Denis; Kurbatova, Olga; Goldenkova-Pavlova, Irina; Nasedkina, Tatyana

    2010-06-01

    Xenobiotic-metabolizing genes (e.g., Cytochromes P450, GST, NAT2, and NQO1), folate metabolism genes (e.g., MTHFR and MTRR), and major histocompatibility complex genes (e.g., HLA-DQA1) play multiple roles in the organism functioning. In addition, AB0 is the most clinically significant high-polymorphic gene in transfusion and transplantation medicine. Epidemiological data show that allele frequencies of these genes exhibit ethnic and geographic diversity. Besides, little is known about frequency distribution of the major polymorphic variants in native Russians. We developed biological microchips that allow us to analyze a spectrum of allelic variants in 12 different genes: CYP1A1, CYP2D6, CYP2C9, CYP2C19, GSTT1, GSTM1, MTHFR, MTRR, NQO1, NAT2, HLA-DQA1, and AB0. Using this composite methodological platform we have studied 352 DNA samples from healthy native Russian volunteers. The allelic frequencies of gene polymorphisms obtained are close to allelic frequencies observed in some European populations, as published earlier. These data were used in comparative studies to determine predisposition to tuberculosis, lymphoma, and leukemia in adults and to childhood acute leukemia. The HLA-DQA1 and AB0 allele frequencies were used to estimate forensic population parameters for these loci. PMID:20373852

  11. Ankle sprain: pathophysiology, predisposing factors, and management strategies

    PubMed Central

    Hubbard, Tricia J; Wikstrom, Erik A

    2010-01-01

    With the high percentage (up to 75%) of initial lateral ankle sprains (LAS) leading to repetitive sprains and chronic symptoms, it is imperative to better understand how best to treat and rehabilitate LAS events. The purpose of this paper is to review LAS pathophysiology, predisposing factors, and the current evidence regarding therapeutic modalities and exercises used in the treatment of LAS. Functional rehabilitation, early mobilization with support, is the current standard of care for LAS. However, the high percentage of reinjury occurrence and development of chronic symptoms (up to 75%) after a LAS, suggests the current standard of care may not be effective. Recent evidence has shown the need for more stringent immobilization to facilitate ligament healing and restoration of joint stability and function after a LAS. Additionally, the importance of adding adjunctive therapies, specifically joint mobilizations and balance training have been shown to improve function and decrease the incidence of reinjury after a LAS. Modifying current rehabilitation protocols to include protecting the ankle joint with stringent immobilization, and including joint mobilizations and balance training may be the first step to decreasing the incidence of short and long term ankle joint dysfunction. PMID:24198549

  12. Malignant melanoma in a black child: predisposing precursors and management.

    PubMed Central

    Adedoyin, Olanrewaju T.; Johnson, Abdul-Wahab B. R.; Ojuawo, Ayodele I.; Afolayan, Enoch A. O.; Adeniji, Kayode A.

    2004-01-01

    Malignant melanoma (MM) remains a pediatric rarity world-wide, but perhaps more so in black Africans. To the best of our knowledge, the current report of MM in a two-and-a-half-year-old Nigerian who had a pre-existing congenital giant hairy nevus is probably the first (in an accessible literature) in a black African child. Primary neoplastic transformation and metastatic spread were suggested by the appearance of multiple swellings over the "garment" precursor nevus at the posterior trunk, multiple ipsilateral axillary nodal enlargement, and fresh occipital swellings postadmission. Smaller-sized hyperpigmented lesions with irregular, nonlobulated, and frequently hairy surfaces were also discernible over the upper and lower extremities, but the face, anterior trunk, and mucosal surfaces were relatively spared. A diagnosis of MM was confirmed by the subsequent histopathologic findings from the fine-needle aspirate and biopsy specimens. Chemotherapy was initiated but was truncated shortly after by parent-pressured discharge. Despite the rarity of MM in a tropical African setting where management options are few, the current case underscores the need for a high clinical index of diagnostic suspicion, an early pursuit of investigative confirmation, and prophylactic excision in children with the predisposing skin lesions, like congenital giant hairy nevus. An expounded discourse of the possible precursors and management options of MM is provided. We emphasize the need for institutional cost subsidy for anticancer care in tropical children. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:15540891

  13. Association between the MTHFR A1298C polymorphism and risk of cancer: evidence from 265 case-control studies.

    PubMed

    Zhu, Xin-Li; Liu, Zhi-Zhong; Yan, Sen-Xiang; Wang, Wei; Chang, Rui-Xia; Zhang, Chun-Yan; Guo, Yan

    2016-02-01

    Many molecular, epidemiological studies have been performed to explore the association between MTHFR A1298C polymorphism and cancer risk. However, the results were inconsistent or even contradictory. Hence, we performed a meta-analysis to investigate the association between cancer risk and MTHFR A1298C (81,040 cases and 114,975 controls from 265 studies) polymorphism. Overall, significant association was observed between MTHFR A1298C polymorphism and cancer risk when all eligible studies were pooled into the meta-analysis. In further stratified and sensitivity analyses, significantly increased cervical cancer (dominant model: OR 1.46, 95 % CI 1.13-1.90; AC vs. AA: OR 1.48, 95 % CI 1.13-1.92) and lymphoma (dominant model: OR 1.22, 95 % CI 1.04-1.44; recessive model: OR 1.66, 95 % CI 1.15-2.39; CC vs. AA: OR 1.75, 95 % CI 1.21-2.53) risk were observed in Asians, and significantly decreased colorectal cancer risk was found in Asians (recessive model: OR 0.75, 95 % CI 0.59-0.96; CC vs. AA: OR 0.77, 95 % CI 0.60-1.00). In summary, this meta-analysis suggests that MTHFR A1298C polymorphism is associated with increased cervical cancer and lymphoma risk in Asians, and MTHFR A1298C polymorphism is associated with decreased colorectal cancer risk in Asians. Moreover, this meta-analysis also points out the importance of new studies, such as oral cancer and chronic myeloid leukemia, because they had high heterogeneity in this meta-analysis (I (2) > 75 %). PMID:26156333

  14. Quantitative proteomics reveals differentially expressed proteins in murine preneoplastic intestine in a model of intestinal tumorigenesis induced by low dietary folate and MTHFR deficiency.

    PubMed

    Leclerc, Daniel; Dejgaard, Kurt; Mazur, Alexander; Deng, Liyuan; Wu, Qing; Nilsson, Tommy; Rozen, Rima

    2014-11-01

    Colorectal cancer risk is increased when dietary folate intake is low, with or without a deficiency in methylenetetrahydrofolate reductase (MTHFR). We have observed that intestinal tumors are induced in mice fed low-folate diets, and that tumor incidence is increased when these mice also have MTHFR deficiency. This study was undertaken to identify differentially expressed proteins in conditions favoring initial steps of murine carcinogenesis in normal preneoplastic intestine. We compared the proteome of BALB/c normal intestine in Mthfr(+/+) mice fed control diets for 1 year (low susceptibility to tumorigenesis) with the proteome of Mthfr(+/-) animals fed low folate diets (higher tumor susceptibility). Our data suggest that the NuRD complex, KRAS-related proteins, the protein synthetic machinery, and fatty acid-related metabolic proteins are upregulated in the early stages of tumorigenesis. These proteins may serve as biomarkers or targets for colorectal cancer diagnosis or therapy. PMID:25081070

  15. Somatic Overgrowth Predisposes to Seizures in Autism Spectrum Disorders

    PubMed Central

    Brachini, Francesca; Apicella, Fabio; Cosenza, Angela; Ferrari, Anna Rita; Guerrini, Renzo; Muratori, Filippo; Romano, Maria Francesca; Santorelli, Filippo M.; Tancredi, Raffaella; Sicca, Federico

    2013-01-01

    Background Comorbidity of Autism Spectrum Disorders with seizures or abnormal EEG (Autism-Epilepsy Phenotype) suggests shared pathomechanisms, and might be a starting point to identify distinct populations within the clinical complexity of the autistic spectrum. In this study, we tried to assess whether distinct subgroups, having distinctive clinical hallmarks, emerge from this comorbid condition. Methods Two-hundred and six individuals with idiopathic Autism Spectrum Disorders were subgrouped into three experimental classes depending on the presence of seizures and EEG abnormalities. Neurobehavioral, electroclinical and auxological parameters were investigated to identify differences among groups and features which increase the risk of seizures. Our statistical analyses used ANOVA, post-hoc multiple comparisons, and the Chi-squared test to analyze continuous and categorical variables. A correspondence analysis was also used to decompose significant Chi-squared and reduce variables dimensions. Results The high percentage of children with seizures (28.2% of our whole cohort) and EEG abnormalities (64.1%) confirmed that the prevalence of epilepsy in Autism Spectrum Disorders exceeds that of the general population. Seizures were associated with severe intellectual disability, and not with autism severity. Interestingly, tall stature (without macrocephaly) was significantly associated with EEG abnormalities or later onset seizures. However, isolated macrocephaly was equally distributed among groups or associated with early onset seizures when accompanied by tall stature. Conclusions Tall stature seems to be a phenotypic “biomarker” of susceptibility to EEG abnormalities or late epilepsy in Autism Spectrum Disorders and, when concurring with macrocephaly, predisposes to early onset seizures. Growth pattern might act as an endophenotypic marker in Autism-Epilepsy comorbidity, delineating distinct pathophysiological subtypes and addressing personalized diagnostic work-up and therapeutic approaches. PMID:24086423

  16. [Speech impairment predisposes to cognitive deterioration in hepatic encephalopathy].

    PubMed

    Meparidze, M M; Kodua, T E; Lashkhi, K S

    2010-04-01

    Hepatic encephalopathy is a reversible neuro-psychiatric syndrome that complicates liver insufficiency. The changes are complex and disorders are detected in digestive and neural systems. Disturbed consciousness and intellectual deterioration, particularly communicative difficulties are observed: speech is slurred, voice monotonous, writing disturbances, amimic face and rigid posture. Difficulties of socialization and tendency to self-isolation are observed. Memory, attention and perception are decreased. We suppose that disorders of cognitive functions are determined by impairment of speech and other communicative abilities. According to the theories of linguistic determinism and linguistic relativity thought categories move through the mould of native language. That means, speech impairment causes misperception of the real world. To confirm this hypothesis we investigated 106 patients with following diseases: peptic ulcer - 46, fatty liver - 30, liver cirrhosis - 19, viral hepatitis - 11 and 19 controls. Brain magnetic resonance tomography was carried out and psychometric tests were performed to patients with symptoms of hepatic encephalopathy. Atrophic changes in frontal, temporal and insular area of brain cortex were revealed in most cases. Those regions are responsible for actor observation, imitation and emotion, i.e. for empathy and sociability. They are very sensitive to the increased levels of ammonia and glutamine. In case of early treatment only slight atrophic changes are presented but without treatment atrophic processes become stable and expressed by impairments of speech and entire communicative ability. Human beings are very much at the mercy of the particular language which has become the medium of expression for their society. They do not live in the objective world alone, or in the world of social activity alone. Accordingly, damage of speech in hepatic encephalopathy is primary and predisposes to cognitive dysfunction. PMID:20495225

  17. Feline immunodeficiency virus predisposes cats to acute generalized toxoplasmosis.

    PubMed Central

    Davidson, M. G.; Rottman, J. B.; English, R. V.; Lappin, M. R.; Tompkins, M. B.

    1993-01-01

    This study was designed to examine the effects of a pre-existing, clinically asymptomatic feline immunodeficiency virus (FIV) infection on a primary challenge with Toxoplasma gondii. Parenteral challenge of FIV-infected cats with tachyzoites of the ME49 strain of T. gondii caused a precipitous drop in all lymphocytes (CD4+, CD8+, and B cells) and generalized severe toxoplasmosis. The predominant postmortem lesions included acute and often fatal interstitial pneumonia, dominated histologically by macrophages, and multifocal to coalescing hepatic necrosis. Immunohistochemistry revealed numerous T. gondii antigen and tachyzoites in macrophages and other cell types in the lung lesions. The proliferative response of peripheral blood mononuclear cells to specific (T. gondii antigen) and nonspecific (Concanavalin A) mitogens was defective in the dually infected cats, suggesting marked immunosuppression. In contrast to the dually infected cats, cats infected only with T. gondii developed a transient, mild clinical disease characterized by anorexia, lethargy, and multifocal chorioretinitis. Lymphocyte changes in T. gondii-infected cats included an early pan-lymphopenia followed by reestablishment of all lymphocyte subset profiles. These cats also showed a reduced proliferative response to Concanavalin A at 1 week after challenge, but a measurable in vivo response to T. gondii antigens, as evidenced by in vitro lymphocyte proliferation in the absence of a mitogenic stimulus. These results show that infection of cats with FIV-NCSU, markedly enhances their susceptibility to a primary T. gondii infection and provides a model to study the mechanisms of the underlying immunological defect(s) occurring early after HIV infection that may predispose individuals to development of acquired immunodeficiency syndrome and associated diseases. Images Figure 4 PMID:8238262

  18. Recurrent ischemic strokes in a young celiac woman with MTHFR gene mutation

    PubMed Central

    Fabbri, Elisa; Rustignoli, Lisa; Muscari, Antonio; Puddu, Giovanni M; Guarino, Maria; Rinaldi, Rita; Minguzzi, Elena; Caio, Giacomo; Zoli, Marco; Volta, Umberto

    2012-01-01

    Celiac disease (CD) is frequently associated with neurological disorders, but very few reports concern the association with ischemic stroke. A 26-year-old woman affected by CD with secondary amenorrhea, carrier of a homozygous 5,10-methylenetetrahydrofolate reductase mutation with hyperhomocysteinemia, was affected by two occipital ischemic strokes within a period of 5 mo. At the time of the second stroke, while she was being treated with folic acid, acetylsalicylic acid and a gluten-free diet, she had left hemianopsia, left hemiparesthesias, and gait imbalance. Brain magnetic resonance imaging showed a subacute right occipital ischemic lesion, which was extended to the dorsal region of the right thalamus and the ipsilateral thalamo-capsular junction. Antitransglutaminase and deamidated gliadin peptide antibodies were no longer present, while antinuclear antibodies, antineuronal antibodies and immune circulating complexes were only slightly elevated. Since the patient was taking folic acid, her homocysteine ??levels were almost normal and apparently not sufficient alone to explain the clinical event. A conventional cerebral angiography showed no signs of vasculitis. Finally, rare causes of occipital stroke in young patients, such as Fabry’s disease and mitochondrial myopathy, encephalomyopathy, lactic acidosis and stroke-like symptoms, were also excluded by appropriate tests. Thus, the most probable cause for the recurrent strokes in this young woman remained CD, although the mechanisms involved are still unknown. The two main hypotheses concern malabsorption (with consequent deficiency of vitamins known to exert neurotrophic and neuroprotective effects) and immune-mediated mechanisms. CD should be kept in mind in the differential diagnosis of ischemic stroke in young patients. PMID:22807619

  19. A novel recurrent mutation in MITF predisposes to familial and sporadic melanoma

    PubMed Central

    Yokoyama, Satoru; Woods, Susan L.; Boyle, Glen M.; Aoude, Lauren G.; MacGregor, Stuart; Zismann, Victoria; Gartside, Michael; Cust, Anne E.; Haq, Rizwan; Harland, Mark; Taylor, John C.; Duffy, David L.; Holohan, Kelly; Dutton-Regester, Ken; Palmer, Jane M.; Bonazzi, Vanessa; Stark, Mitchell S.; Symmons, Judith; Law, Matthew H.; Schmidt, Christopher; Lanagan, Cathy; O’Connor, Linda; Holland, Elizabeth A.; Schmid, Helen; Maskiell, Judith A.; Jetann, Jodie; Ferguson, Megan; Jenkins, Mark A.; Kefford, Richard F.; Giles, Graham G.; Armstrong, Bruce K.; Aitken, Joanne F.; Hopper, John L.; Whiteman, David C.; Pharoah, Paul D.; Easton, Douglas F.; Dunning, Alison M.; Newton-Bishop, Julia A.; Montgomery, Grant W.; Martin, Nicholas G.; Mann, Graham J.; Bishop, D. Timothy; Tsao, Hensin; Trent, Jeffrey M.; Fisher, David E.; Hayward, Nicholas K.; Brown, Kevin M.

    2012-01-01

    So far, two familial melanoma genes have been identified, accounting for a minority of genetic risk in families. Mutations in CDKN2A account for approximately 40% of familial cases1, and predisposing mutations in CDK4 have been reported in a very small number of melanoma kindreds2. To identify other familial melanoma genes, here we conducted whole-genome sequencing of probands from several melanoma families, identifying one individual carrying a novel germline variant (coding DNA sequence c.G1075A; protein sequence p.E318K; rs149617956) in the melanoma-lineage-specific oncogene microphthalmia-associated transcription factor (MITF). Although the variant co-segregated with melanoma in some but not all cases in the family, linkage analysis of 31 families subsequently identified to carry the variant generated a log odds ratio (lod) score of 2.7 under a dominant model, indicating E318K as a possible intermediate risk variant. Consistent with this, the E318K variant was significantly associated with melanoma in a large Australian case–control sample. Likewise, it was similarly associated in an independent case–control sample from the United Kingdom. In the Australian sample, the variant allele was significantly over-represented in cases with a family history of melanoma, multiple primary melanomas, or both. The variant allele was also associated with increased naevus count and non-blue eye colour. Functional analysis of E318K showed that MITF encoded by the variant allele had impaired sumoylation and differentially regulated several MITF targets. These data indicate that MITF is a melanoma-predisposition gene and highlight the utility of whole-genome sequencing to identify novel rare variants associated with disease susceptibility. PMID:22080950

  20. Fc-Gamma Receptor Polymorphisms Predispose Patients to Infectious Complications After Liver Transplantation.

    PubMed

    Shimizu, S; Tanaka, Y; Tazawa, H; Verma, S; Onoe, T; Ishiyama, K; Ohira, M; Ide, K; Ohdan, H

    2016-02-01

    We investigated the impact of polymorphisms in host innate immunoregulatory genes on the development of infectious complications after liver transplantation (LT). The single-nucleotide polymorphisms (SNPs) of C1QA [276A/G], FCGR2A [131H/R], and FCGR3A [158F/V], genes encoding the Fc gamma receptor (Fc?R), were analyzed in 89 living donor LT recipients in relation to the occurrences of postoperative infectious complications within 30 days after LT. Consistent with a lower affinity of the isoform encoded by FCGR3A [158F] to both IgG1 and IgG3, a significantly higher incidence of bloodstream infections (BSI) was observed in the FCGR3A [158F/V or F/F] than in the FCGR3A [158V/V] individuals. The combination of FCGR2A and FCGR3A SNPs further stratified the incidence of BSI, regardless of C1QA SNP. The predominant causative pathogen of BSI in the FCGR3A [158F/F or F/V] patients was gram-positive cocci (73.3%), of which one third was methicillin-resistant Staphylococcus aureus. No differences were observed in the incidence of fungal infections or in cytomegalovirus infections with respect to the three gene polymorphisms. Our findings indicate that Fc?R SNPs are predisposing factors for BSI and can predict mortality after LT. This study provides a foundation for further prospective studies on a larger scale. PMID:26517570

  1. Polymorphisms in methylenetetrahydrofolate reductase gene and risk of non-Hodgkin lymphoma in a multi-ethnic population.

    PubMed

    Suthandiram, Sujatha; Gan, Gin Gin; Zain, Shamsul Mohd; Haerian, Batoul Sadat; Bee, Ping Chong; Lian, Lay Hoong; Chang, Kian Meng; Ong, Tee Chuan; Mohamed, Zahurin

    2014-05-01

    An imbalance in folate metabolism can adversely affect DNA synthesis and methylation systems which can lead to susceptibility to non-Hodgkin lymphoma (NHL). Whether single nucleotide polymorphisms (SNPs) and their haplotypes in the methylenetetrahydrofolate reductase (MTHFR) are associated with NHL, remain inconclusive. We investigated the association between MTHFR C677T and A1298C SNPs and NHL risk in a population which is made up of Malay, Chinese and Indian ethnic subgroups. A total of 372 NHL patients and 722 controls were genotyped using the Sequenom MassARRAY platform. Our results of the pooled subjects failed to demonstrate significant association between the MTHFR C677T and A1298C SNPs with NHL and its subtypes. The results were in agreement with the previous meta-analyses. In the Indian ethnic subgroup however, single locus analysis of MTHFR A1298C appears to confer risk to NHL (Odds ratio (OR) 1.91, 95% confidence interval (95% CI) 1.22-3.00, P=0.006). The risk is almost doubled in homozygous carrier of MTHFR 1298CC (OR 4.03, 95% CI 1.56-10.43, P=0.004). Haplotype analysis revealed higher frequency of CC in the Indian NHL patients compared with controls (OR 1.86, 95% CI 1.18-2.93, P=0.007). There is lack of evidence to suggest an association between MTHFR C677T and A1298C with the risk of NHL in the Malays and Chinese. In the Indians however, the MTHFR A1298C confers risk to NHL. This study suggests ethnicity modifies the relationship between polymorphisms in the folate-metabolizing gene and NHL. PMID:24646728

  2. Predictive genetic testing in children: constitutional mismatch repair deficiency cancer predisposing syndrome.

    PubMed

    Bruwer, Zandrè; Algar, Ursula; Vorster, Alvera; Fieggen, Karen; Davidson, Alan; Goldberg, Paul; Wainwright, Helen; Ramesar, Rajkumar

    2014-04-01

    Biallelic germline mutations in mismatch repair genes predispose to constitutional mismatch repair deficiency syndrome (CMMR-D). The condition is characterized by a broad spectrum of early-onset tumors, including hematological, brain and bowel and is frequently associated with features of Neurofibromatosis type 1. Few definitive screening recommendations have been suggested and no published reports have described predictive testing. We report on the first case of predictive testing for CMMR-D following the identification of two non-consanguineous parents, with the same heterozygous mutation in MLH1: c.1528C > T. The genetic counseling offered to the family, for their two at-risk daughters, is discussed with a focus on the ethical considerations of testing children for known cancer-causing variants. The challenges that are encountered when reporting on heterozygosity in a child younger than 18 years (disclosure of carrier status and risk for Lynch syndrome), when discovered during testing for homozygosity, are addressed. In addition, the identification of CMMR-D in a three year old, and the recommended clinical surveillance that was proposed for this individual is discussed. Despite predictive testing and presymptomatic screening, the sudden death of the child with CMMR-D syndrome occurred 6 months after her last surveillance MRI. This report further highlights the difficulty of developing guidelines, as a result of the rarity of cases and diversity of presentation. PMID:24122200

  3. Chromosome 21 scan in Down syndrome reveals DSCAM as a predisposing locus in Hirschsprung disease.

    PubMed

    Jannot, Anne-Sophie; Pelet, Anna; Henrion-Caude, Alexandra; Chaoui, Asma; Masse-Morel, Marine; Arnold, Stacey; Sanlaville, Damien; Ceccherini, Isabella; Borrego, Salud; Hofstra, Robert M W; Munnich, Arnold; Bondurand, Nadège; Chakravarti, Aravinda; Clerget-Darpoux, Françoise; Amiel, Jeanne; Lyonnet, Stanislas

    2013-01-01

    Hirschsprung disease (HSCR) genetics is a paradigm for the study and understanding of multigenic disorders. Association between Down syndrome and HSCR suggests that genetic factors that predispose to HSCR map to chromosome 21. To identify these additional factors, we performed a dose-dependent association study on chromosome 21 in Down syndrome patients with HSCR. Assessing 10,895 SNPs in 26 Caucasian cases and their parents led to identify two associated SNPs (rs2837770 and rs8134673) at chromosome-wide level. Those SNPs, which were located in intron 3 of the DSCAM gene within a 19 kb-linkage disequilibrium block region were in complete association and are consistent with DSCAM expression during enteric nervous system development. We replicated the association of HSCR with this region in an independent sample of 220 non-syndromic HSCR Caucasian patients and their parents. At last, we provide the functional rationale to the involvement of DSCAM by network analysis and assessment of SOX10 regulation. Our results reveal the involvement of DSCAM as a HSCR susceptibility locus, both in Down syndrome and HSCR isolated cases. This study further ascertains the chromosome-scan dose-dependent methodology used herein as a mean to map the genetic bases of other sub-phenotypes both in Down syndrome and other aneuploidies. PMID:23671607

  4. Chromosome 21 Scan in Down Syndrome Reveals DSCAM as a Predisposing Locus in Hirschsprung Disease

    PubMed Central

    Jannot, Anne-Sophie; Chaoui, Asma; Masse-Morel, Marine; Arnold, Stacey; Sanlaville, Damien; Ceccherini, Isabella; Borrego, Salud; Hofstra, Robert M. W.; Munnich, Arnold; Bondurand, Nadège; Chakravarti, Aravinda; Clerget-Darpoux, Françoise; Amiel, Jeanne; Lyonnet, Stanislas

    2013-01-01

    Hirschsprung disease (HSCR) genetics is a paradigm for the study and understanding of multigenic disorders. Association between Down syndrome and HSCR suggests that genetic factors that predispose to HSCR map to chromosome 21. To identify these additional factors, we performed a dose-dependent association study on chromosome 21 in Down syndrome patients with HSCR. Assessing 10,895 SNPs in 26 Caucasian cases and their parents led to identify two associated SNPs (rs2837770 and rs8134673) at chromosome-wide level. Those SNPs, which were located in intron 3 of the DSCAM gene within a 19 kb-linkage disequilibrium block region were in complete association and are consistent with DSCAM expression during enteric nervous system development. We replicated the association of HSCR with this region in an independent sample of 220 non-syndromic HSCR Caucasian patients and their parents. At last, we provide the functional rationale to the involvement of DSCAM by network analysis and assessment of SOX10 regulation. Our results reveal the involvement of DSCAM as a HSCR susceptibility locus, both in Down syndrome and HSCR isolated cases. This study further ascertains the chromosome-scan dose-dependent methodology used herein as a mean to map the genetic bases of other sub-phenotypes both in Down syndrome and other aneuploidies. PMID:23671607

  5. Genome-wide association study identifies novel loci predisposing to cutaneous melanoma†

    PubMed Central

    Amos, Christopher I.; Wang, Li-E; Lee, Jeffrey E.; Gershenwald, Jeffrey E.; Chen, Wei V.; Fang, Shenying; Kosoy, Roman; Zhang, Mingfeng; Qureshi, Abrar A.; Vattathil, Selina; Schacherer, Christopher W.; Gardner, Julie M.; Wang, Yuling; Tim Bishop, D.; Barrett, Jennifer H.; MacGregor, Stuart; Hayward, Nicholas K.; Martin, Nicholas G.; Duffy, David L.; Mann, Graham J.; Cust, Anne; Hopper, John; Brown, Kevin M.; Grimm, Elizabeth A.; Xu, Yaji; Han, Younghun; Jing, Kaiyan; McHugh, Caitlin; Laurie, Cathy C.; Doheny, Kim F.; Pugh, Elizabeth W.; Seldin, Michael F.; Han, Jiali; Wei, Qingyi

    2011-01-01

    We performed a multistage genome-wide association study of melanoma. In a discovery cohort of 1804 melanoma cases and 1026 controls, we identified loci at chromosomes 15q13.1 (HERC2/OCA2 region) and 16q24.3 (MC1R) regions that reached genome-wide significance within this study and also found strong evidence for genetic effects on susceptibility to melanoma from markers on chromosome 9p21.3 in the p16/ARF region and on chromosome 1q21.3 (ARNT/LASS2/ANXA9 region). The most significant single-nucleotide polymorphisms (SNPs) in the 15q13.1 locus (rs1129038 and rs12913832) lie within a genomic region that has profound effects on eye and skin color; notably, 50% of variability in eye color is associated with variation in the SNP rs12913832. Because eye and skin colors vary across European populations, we further evaluated the associations of the significant SNPs after carefully adjusting for European substructure. We also evaluated the top 10 most significant SNPs by using data from three other genome-wide scans. Additional in silico data provided replication of the findings from the most significant region on chromosome 1q21.3 rs7412746 (P = 6 × 10?10). Together, these data identified several candidate genes for additional studies to identify causal variants predisposing to increased risk for developing melanoma. PMID:21926416

  6. Role of plasma homocysteine levels and MTHFR polymorphisms on IQ scores in children and young adults with epilepsy treated with antiepileptic drugs.

    PubMed

    Di Rosa, Gabriella; Lenzo, Patrizia; Parisi, Eleonora; Neri, Milena; Guerrera, Silvia; Nicotera, Antonio; Alibrandi, Angela; Germanò, Eva; Caccamo, Daniela; Spanò, Maria; Tortorella, Gaetano

    2013-12-01

    Homocysteine (Hcy) is a sulfur-containing amino acid involved in methionine metabolism. High plasma total Hcy (tHcy) has been quite frequently reported in patients with epilepsy treated with antiepileptic drugs (AEDs) mainly related to plasma folate reduction induced by AEDs themselves. The role of C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene (MTHFR) on the increase of plasma tHcy in patients with epilepsy taking AEDs is still controversial. Cognitive impairment may be associated with epilepsy either as the result of the epileptic syndrome per se or as a side effect induced by the AEDs. High plasma tHcy levels were associated with lower cognitive performances in patients affected by Alzheimer's disease and mild cognitive impairment and in healthy elderly. We searched for a correlation between plasma tHcy levels with the intelligence quotient (IQ) scores in a population of children and young adults with epilepsy treated with old and/or newer AEDs. The study group encompassed 179 patients (92 M, 51.5%) followed at our Unit of Child Neuropsychiatry and aged between 4 and 25years (mean+SD: 14.03±4.25). The inclusion criteria included the following: 1) diagnosis of epilepsy of "unknown cause" (cryptogenic) according to the ILAE classification, 2) age older than 3years, 3) stabilized antiepileptic treatment for at least 6months, and 4) clinical records of cognitive tests, plasma tHcy value, and results of MTHFR polymorphisms. Patients' mean tHcy value was 9.71±3.13?M/L (tHcy<9?M/L as our laboratory cutoff in nonepileptic controls). The mean TIQ score was 85.22 (SD±24.12); the mean VIQ score was 86.32 (SD±20.86); and the mean PIQ score was 86.94 (SD±21.51). C677T and A1298C MTHFR polymorphisms were detected in 74/92 (80%) examined patients and distributed into the following: CT (22.3%), TT (14.9%), CC (10.3%) for C677T, AC (16%), CC (1.1%), and AA (30.3%) for A1298C. Plasma tHcy levels were not significantly related to the IQ scores (TIQ, VIQ, or PIQ). Two significant findings came out. First, patients on AED polytherapy showed significantly lower TIQ, VIQ, and PIQ scores compared with the ones with AED monotherapy (p=0.032; p=0.008; p=0.005, respectively). However, this significant difference was not observed with the plasma tHcy levels compared with AED treatment. Second, patients with the 677TT genotype showed significantly higher tHcy levels versus those with the wt ones (p=0.049). In the latter group of patients, although the mean TIQ score was lower compared with the mean TIQ score in those with the wt ones, the difference only approached statistical significance (p=0.056). To our knowledge, this is the first study investigating the relationship between tHcy levels and cognitive scores in children with epilepsy treated with AEDs. Analysis of wider samples, selective neuropsychological tests, and prospective recruitment of patients might be encouraged. PMID:24183735

  7. 32 CFR 644.389 - Army military-modified predisposal procedures where E.O. 11954 surveys have been made.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Army military-modified predisposal procedures... (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Predisposal Action § 644.389 Army military—modified predisposal procedures where E.O. 11954 surveys have been made. (a)...

  8. 32 CFR 644.389 - Army military-modified predisposal procedures where E.O. 11954 surveys have been made.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Army military-modified predisposal procedures... (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Predisposal Action § 644.389 Army military—modified predisposal procedures where E.O. 11954 surveys have been made. (a)...

  9. 32 CFR 644.389 - Army military-modified predisposal procedures where E.O. 11954 surveys have been made.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Army military-modified predisposal procedures... (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Predisposal Action § 644.389 Army military—modified predisposal procedures where E.O. 11954 surveys have been made. (a)...

  10. 32 CFR 644.389 - Army military-modified predisposal procedures where E.O. 11954 surveys have been made.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Army military-modified predisposal procedures... (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Predisposal Action § 644.389 Army military—modified predisposal procedures where E.O. 11954 surveys have been made. (a)...

  11. Quantitative assessment of the associations between MTHFR C677T and A1298C polymorphisms and risk of fractures: a meta-analysis.

    PubMed

    Bai, Rui; Liu, Wanlin; Zhao, Aiqing; Zhao, Zhenqun; Jiang, Dianming

    2013-03-01

    Many studies have investigated the associations between methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and risk of fractures, but the impact of MTHFR polymorphisms on fractures risk is unclear owing to the obvious inconsistence among those studies. This study aims to quantify the strength of association between MTHFR C677T and A1298C polymorphisms and risk of fractures. We searched the PubMed, Embase and Wanfang databases for articles relating the association between MTHFR C677T and A1298C polymorphisms and risk of fractures in humans. We estimated summary odds ratios (ORs) with their confidence intervals (CIs) to assess the associations. Meta-analyses suggested MTHFR C677T polymorphism was associated with increased risk of any site fractures (for T vs. C, OR = 1.17, 95 % CI 1.03-1.32; for TT vs. CC, OR = 1. 31, 95 % CI 1.11-1.54; for TT vs. CT, OR = 1.22, 95 % CI 1.04-1.43; for TT vs. CT/CC, OR = 1.31, 95 % CI 1.13-1.51). Besides, MTHFR A1298C polymorphism was also associated with increased risk of any site fractures. Subgroup meta-analyses suggested MTHFR C677T polymorphism was associated with increased risk of vertebral fractures under three genetic contrast modes (for TT vs. CC, OR = 1.43, 95 % CI 1.05-1.95; for TT vs. CT, OR = 1.36, 95 % CI 1.01-1.85; for TT vs. CT/CC, OR = 1.50, 95 % CI 1.17-1.91), but there was no association between MTHFR C677T polymorphism and risk of hip fractures and non-vertebral fractures (all P values were more than 0.05). Thus, individuals with homozygote genotype TT of MTHFR C677T have obviously increased risk of vertebral fractures compared those with heterozygote genotype CT or homozygote genotype CC. There is no association between MTHFR C677T polymorphism and risk of hip fractures and non-vertebral fractures. PMID:23229495

  12. Common variants at the MHC locus and at chromosome 16q24.1 predispose to Barrett's esophagus.

    PubMed

    Su, Zhan; Gay, Laura J; Strange, Amy; Palles, Claire; Band, Gavin; Whiteman, David C; Lescai, Francesco; Langford, Cordelia; Nanji, Manoj; Edkins, Sarah; van der Winkel, Anouk; Levine, David; Sasieni, Peter; Bellenguez, Céline; Howarth, Kimberley; Freeman, Colin; Trudgill, Nigel; Tucker, Art T; Pirinen, Matti; Peppelenbosch, Maikel P; van der Laan, Luc J W; Kuipers, Ernst J; Drenth, Joost P H; Peters, Wilbert H; Reynolds, John V; Kelleher, Dermot P; McManus, Ross; Grabsch, Heike; Prenen, Hans; Bisschops, Raf; Krishnadath, Kausila; Siersema, Peter D; van Baal, Jantine W P M; Middleton, Mark; Petty, Russell; Gillies, Richard; Burch, Nicola; Bhandari, Pradeep; Paterson, Stuart; Edwards, Cathryn; Penman, Ian; Vaidya, Kishor; Ang, Yeng; Murray, Iain; Patel, Praful; Ye, Weimin; Mullins, Paul; Wu, Anna H; Bird, Nigel C; Dallal, Helen; Shaheen, Nicholas J; Murray, Liam J; Koss, Konrad; Bernstein, Leslie; Romero, Yvonne; Hardie, Laura J; Zhang, Rui; Winter, Helen; Corley, Douglas A; Panter, Simon; Risch, Harvey A; Reid, Brian J; Sargeant, Ian; Gammon, Marilie D; Smart, Howard; Dhar, Anjan; McMurtry, Hugh; Ali, Haythem; Liu, Geoffrey; Casson, Alan G; Chow, Wong-Ho; Rutter, Matt; Tawil, Ashref; Morris, Danielle; Nwokolo, Chuka; Isaacs, Peter; Rodgers, Colin; Ragunath, Krish; MacDonald, Chris; Haigh, Chris; Monk, David; Davies, Gareth; Wajed, Saj; Johnston, David; Gibbons, Michael; Cullen, Sue; Church, Nicholas; Langley, Ruth; Griffin, Michael; Alderson, Derek; Deloukas, Panos; Hunt, Sarah E; Gray, Emma; Dronov, Serge; Potter, Simon C; Tashakkori-Ghanbaria, Avazeh; Anderson, Mark; Brooks, Claire; Blackwell, Jenefer M; Bramon, Elvira; Brown, Matthew A; Casas, Juan P; Corvin, Aiden; Duncanson, Audrey; Markus, Hugh S; Mathew, Christopher G; Palmer, Colin N A; Plomin, Robert; Rautanen, Anna; Sawcer, Stephen J; Trembath, Richard C; Viswanathan, Ananth C; Wood, Nicholas; Trynka, Gosia; Wijmenga, Cisca; Cazier, Jean-Baptiste; Atherfold, Paul; Nicholson, Anna M; Gellatly, Nichola L; Glancy, Deborah; Cooper, Sheldon C; Cunningham, David; Lind, Tore; Hapeshi, Julie; Ferry, David; Rathbone, Barrie; Brown, Julia; Love, Sharon; Attwood, Stephen; MacGregor, Stuart; Watson, Peter; Sanders, Scott; Ek, Weronica; Harrison, Rebecca F; Moayyedi, Paul; de Caestecker, John; Barr, Hugh; Stupka, Elia; Vaughan, Thomas L; Peltonen, Leena; Spencer, Chris C A; Tomlinson, Ian; Donnelly, Peter; Jankowski, Janusz A Z

    2012-10-01

    Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10(-9); odds ratio (OR)=1.21, 95% confidence interval (CI)=1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (Pcombined=2.74×10(-10); OR=1.14, 95% CI=1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus. PMID:22961001

  13. Common variants at the MHC locus and at chromosome 16q24.1 predispose to Barrett’s esophagus

    PubMed Central

    2012-01-01

    Barrett’s Esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia. Barrett’s Esophagus strongly predisposes to esophageal adenocarcinoma (EAC), a tumour with a very poor prognosis. We have undertaken the first genome-wide association study on Barrett’s Esophagus, comprising 1,852 UK cases and 5,172 UK controls in discovery and 5,986 cases and 12,825 controls in the replication. Two regions were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10?9, OR(95%CI) =1.21(1.13-1.28)) and chromosome 16q24, rs9936833 (Pcombined=2.74×10?10, OR(95%CI) =1.14(1.10-1.19)). The top SNP on chromosome 6p21 is within the major histocompatibility complex, and the closest protein-coding gene to rs9936833 on chromosome 16q24 is FOXF1, which is implicated in esophageal development and structure. We found evidence that the genetic component of Barrett’s Esophagus is mediated by many common variants of small effect and that SNP alleles predisposing to obesity also increase risk for Barrett’s Esophagus. PMID:22961001

  14. COMPARATIVE EVALUATION OF RISK FACTORS FOR CARDIOVASCULAR DISEASE (CVD) IN GENETICALLY PREDISPOSED RATS

    EPA Science Inventory

    Rodent CVD models are increasingly used for understanding individual differences in susceptibility to environmental stressors such as air pollution. We characterized pathologies and a number of known human risk factors of CVD in genetically predisposed, male young adult Spontaneo...

  15. Both Host and Pathogen Factors Predispose to Escherichia coli Urinary-Source Bacteremia in Hospitalized Patients

    PubMed Central

    Marschall, Jonas; Zhang, Lixin; Foxman, Betsy; Warren, David K.; Henderson, Jeffrey P.

    2012-01-01

    Background.?The urinary tract is the most common source for Escherichia coli bacteremia. Mortality from E. coli urinary-source bacteremia is higher than that from urinary tract infection. Predisposing factors for urinary-source E. coli bacteremia are poorly characterized. Methods.?In order to identify urinary-source bacteremia risk factors, we conducted a 12-month prospective cohort study of adult inpatients with E. coli bacteriuria that were tested for bacteremia within ±1 day of the bacteriuria. Patients with bacteremia were compared with those without bacteremia. Bacterial isolates from urine were screened for 16 putative virulence genes using high-throughput dot-blot hybridization. Results.?Twenty-four of 156 subjects (15%) had E. coli bacteremia. Bacteremic patients were more likely to have benign prostatic hyperplasia (56% vs 19%; P = .04), a history of urogenital surgery (63% vs 28%; P = .001), and presentation with hesitancy/retention (21% vs 4%; P = .002), fever (63% vs 38%; P = .02), and pyelonephritis (67% vs 41%; P = .02). The genes kpsMT (group II capsule) (17 [71%] vs 62 [47%]; P = .03) and prf (P-fimbriae family) (13 [54%] vs 40 [30%]; P = .02) were more frequent in the urinary strains from bacteremic patients. Symptoms of hesitancy/retention (odds ratio [OR], 7.8; 95% confidence interval [CI], 1.6–37), history of a urogenital procedure (OR, 5.4; 95% CI, 2–14.7), and presence of kpsMT (OR, 2.9; 95% CI, 1–8.2) independently predicted bacteremia. Conclusions.?Bacteremia secondary to E. coli bacteriuria was frequent (15%) in those tested for it. Urinary stasis, surgical disruption of urogenital tissues, and a bacterial capsule characteristic contribute to systemic invasion by uropathogenic E. coli. PMID:22431806

  16. Association of MTHFR C677T Genotype With Ischemic Stroke Is Confined to Cerebral Small Vessel Disease Subtype

    PubMed Central

    Traylor, Matthew; Adib-Samii, Poneh; Thijs, Vincent; Sudlow, Cathie; Rothwell, Peter M.; Boncoraglio, Giorgio; Dichgans, Martin; Meschia, James; Maguire, Jane; Levi, Christopher; Rost, Natalia S.; Rosand, Jonathan; Hassan, Ahamad; Bevan, Steve; Markus, Hugh S.

    2016-01-01

    Background and Purpose— Elevated plasma homocysteine levels are associated with stroke. However, this might be a reflection of bias or confounding because trials have failed to demonstrate an effect from homocysteine lowering in stroke patients, although a possible benefit has been suggested in lacunar stroke. Genetic studies could potentially overcome these issues because genetic variants are inherited randomly and are fixed at conception. Therefore, we tested the homocysteine levels–associated genetic variant MTHFR C677T for association with magnetic resonance imaging–confirmed lacunar stroke and compared this with associations with large artery and cardioembolic stroke subtypes. Methods— We included 1359 magnetic resonance imaging–confirmed lacunar stroke cases, 1824 large artery stroke cases, 1970 cardioembolic stroke cases, and 14 448 controls, all of European ancestry. Furthermore, we studied 3670 ischemic stroke patients in whom white matter hyperintensities volume was measured. We tested MTHFR C677T for association with stroke subtypes and white matter hyperintensities volume. Because of the established association of homocysteine with hypertension, we additionally stratified for hypertension status. Results— MTHFR C677T was associated with lacunar stroke (P=0.0003) and white matter hyperintensity volume (P=0.04), but not with the other stroke subtypes. Stratifying the lacunar stroke cases for hypertension status confirmed this association in hypertensive individuals (P=0.0002), but not in normotensive individuals (P=0.30). Conclusions— MTHFR C677T was associated with magnetic resonance imaging–confirmed lacunar stroke, but not large artery or cardioembolic stroke. The association may act through increased susceptibility to, or interaction with, high blood pressure. This heterogeneity of association might explain the lack of effect of lowering homocysteine in secondary prevention trials which included all strokes. PMID:26839351

  17. Prediction of Methotrexate Clinical Response in Portuguese Rheumatoid Arthritis Patients: Implication of MTHFR rs1801133 and ATIC rs4673993 Polymorphisms

    PubMed Central

    Lima, Aurea; Monteiro, Joaquim; Bernardes, Miguel; Sousa, Hugo; Azevedo, Rita; Seabra, Vitor; Medeiros, Rui

    2014-01-01

    Objective. Methotrexate (MTX), the most used drug in rheumatoid arthritis (RA) treatment, showing variability in clinical response, is often associated with genetic polymorphisms. This study aimed to elucidate the role of methylenetetrahydrofolate reductase (MTHFR) C677T and aminoimidazole carboxamide adenosine ribonucleotide transformylase (ATIC) T675C polymorphisms and clinicopathological variables in clinical response to MTX in Portuguese RA patients. Methods. Study included 233 RA patients treated with MTX for at least six months. MTHFR C677T and ATIC T675C polymorphisms were genotyped and clinicopathological variables were collected. Statistical analyses were performed and binary logistic regression method adjusted to possible confounding variables. Results. Multivariate analyses demonstrated that MTHFR 677TT (OR = 4.63; P = 0.013) and ATIC 675T carriers (OR = 5.16; P = 0.013) were associated with over 4-fold increased risk for nonresponse. For clinicopathological variables, noncurrent smokers (OR = 7.98; P = 0.001), patients positive to anti-cyclic citrullinated peptide (OR = 3.53; P = 0.004) and antinuclear antibodies (OR = 2.28; P = 0.045), with higher health assessment questionnaire score (OR = 2.42; P = 0.007), and nonsteroidal anti-inflammatory drug users (OR = 2.77; P = 0.018) were also associated with nonresponse. Contrarily, subcutaneous administration route (OR = 0.11; P < 0.001) was associated with response. Conclusion. Our study suggests that MTHFR C677T and ATIC T675C genotyping combined with clinicopathological data may help to identify patients whom will not benefit from MTX treatment and, therefore, assist clinicians in personalizing RA treatment. PMID:24967362

  18. Folate Intake, MTHFR Polymorphisms, and the Risk of Colorectal Cancer: A Systematic Review and Meta-Analysis

    PubMed Central

    Kennedy, Deborah A.; Stern, Seth J.; Matok, Ilan; Moretti, Myla E.; Sarkar, Moumita; Adams-Webber, Thomasin; Koren, Gideon

    2012-01-01

    Background. The objective was to determine whether relationships exist between the methylene-tetrahydrofolate reductase (MTHFR) polymorphisms and risk of colorectal cancer (CRC) and examine whether the risk is modified by level of folate intake. Methods. MEDLINE, Embase, and SCOPUS were searched to May 2012 using the terms “folic acid,” “folate,” “colorectal cancer,” “methylenetetrahydrofolate reductase,” “MTHFR.” Observational studies were included which (1) assessed the risk of CRC for each polymorphism and/or (2) had defined levels of folate intake for each polymorphism and assessed the risk of CRC. Results. From 910 references, 67 studies met our criteria; hand searching yielded 10 studies. The summary risk estimate comparing the 677CT versus CC genotype was 1.02 (95% CI 0.95–1.10) and for 677TT versus CC was 0.88 (95% CI 0.80–0.96) both with heterogeneity. The summary risk estimates for A1298C polymorphisms suggested no reduced risk. The summary risk estimate for high versus low total folate for the 677CC genotype was 0.70 (95% CI 0.56–0.89) and the 677TT genotype 0.63 (95% CI 0.41–0.97). Conclusion. These results suggest that the 677TT genotype is associated with a reduced risk of developing CRC, under conditions of high total folate intake, and this associated risk remains reduced for both MTHFR 677 CC and TT genotypes. PMID:23125859

  19. Variants of human papillomavirus type 16 predispose toward persistent infection

    PubMed Central

    Zhang, Lei; Liao, Hong; Yang, Binlie; Geffre, Christopher P; Zhang, Ai; Zhou, Aizhi; Cao, Huimin; Wang, Jieru; Zhang, Zhenbo; Zheng, Wenxin

    2015-01-01

    A cohort study of 292 Chinese women was conducted to determine the relationship between human papillomavirus (HPV) type 16 variants and persistent viral infection. Enrolled patients were HPV16 positive and had both normal cytology and histology. Flow-through hybridization and gene chip technology was used to identify the HPV type. A PCR sequencing assay was performed to find HPV16 E2, E6 and E7 gene variants. The associations between these variants and HPV16 persistent infection was analyzed by Fisher’s exact test. It was found that the variants T178G, T350G and A442C in the E6 gene, as well as C3158A and G3248A variants in the E2 gene were associated with persistent HPV16 infection. No link was observed between E7 variants and persistent viral infection. Our findings suggest that detection of specific HPV variants would help identify patients who are at high risk for viral persistence and development of cervical neoplasia. PMID:26339417

  20. APOH interacts with FTO to predispose to healthy thinness.

    PubMed

    Hasstedt, Sandra J; Coon, Hilary; Xin, Yuanpei; Adams, Ted D; Hunt, Steven C

    2016-02-01

    We identified eight candidate thinness predisposition variants from the Illumina HumanExome chip genotyped on members of pedigrees selected for either healthy thinness or severe obesity. For validation, we tested the candidates for association with healthy thinness in additional pedigree members while accounting for effects of obesity-associated genes: NPFFR2, NPY2R, FTO, and MC4R. Significance was obtained for the interaction of FTO rs9939609 with APOH missense variant rs52797880 (minor allele frequency 0.054). The thinness odds ratio was estimated as 2.15 (p < 0.05) for the combination of APOH heterozygote with the homozygote for the non-obesity FTO allele. Significance was not obtained for any other combination of a candidate variant with an obesity gene or for any of the eight candidates tested independently. PMID:26711810

  1. Polymorphisms of methylenetetrahydrofolate reductase gene as the genetic predispositions of coronary artery diseases in eastern India

    PubMed Central

    Dhar, Soujatya; Chatterjee, Sumana; Ray, Saumitra; Dutta, Anjanlal; Sengupta, Bani; Chakrabarti, Shila

    2010-01-01

    Background: Gene–environment interaction is an important aspect in the development of coronary artery disease (CAD). The mutation (677C-T) of methylenetetrahydrofolate reductase (MTHFR) gene results in a decrease of the enzyme activity that leads to mild hyperhomocysteinemia. Elevated plasma level of homocysteine has been recognized as an independent risk factor for cardiovascular disease. A case–control study was designed to assess whether the prevalence of some MTHFR gene polymorphisms have any role in the development of CAD. Materials and Methods: The study included unrelated 217 cases with CAD and 255 healthy controls. DNA was extracted from peripheral blood. MTHFR genotypes were identified by seeing the presence or absence of 677C?T mutation obtained by PCR followed by Hinf1 restriction digestion. Multiple logistic regression analysis was carried out to find association between studied genotypes and lifestyle as well as biochemical risk factors. Results: The T allele was found to be associated with the disease. Significant associations were found with smoking, hypertension, diabetes, and family history of CAD. Conclusion: The results indicate that MTHFR 677C-T polymorphism has significant association with CADs in the population of eastern India. PMID:21187870

  2. The methylenetetrahydrofolate reductase gene C677T polymorphism in patients with homozygous sickle cell disease and stroke.

    PubMed

    Cumming, A M; Olujohungbe, A; Keeney, S; Singh, H; Hay, C R; Serjeant, G R

    1999-12-01

    Homozygosity for the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism may cause hyperhomocysteinaemia, a recognized risk factor for stroke, in individuals with folate deficiency. Homozygous sickle cell (SS) disease is associated both with increased demands for folic acid and a tendency to develop stroke. We therefore investigated a possible role of the MTHFR C677T polymorphism in SS disease patients with stroke. Investigation of the frequency of the polymorphism in 48 patients with stroke and in 48 age-, sex- and racially-matched SS controls without stroke failed to reveal a difference between the groups (Fisher exact test, P = 0.99). Homozygosity for the MTHFR C677T polymorphism is unlikely to be a risk factor for stroke in this population with SS disease. PMID:10583261

  3. A non-coding mutation in the 5' untranslated region of patched homologue 1 predisposes to basal cell carcinoma.

    PubMed

    Tietze, Julia K; Pfob, Martina; Eggert, Marlene; von Preußen, Anna; Mehraein, Yasmin; Ruzicka, Thomas; Herzinger, Thomas

    2013-12-01

    Mutations in the human homolog of the Drosophila patched gene, patched homologue 1 (PTCH-1), are responsible for most hereditary and sporadic basal cell carcinomas. Here, we present a father and daughter with a high propensity for the development of basal cell carcinoma who were heterozygous for a non-coding germline mutation in the 5' untranslated region (UTR) of PTCH-1 (insertion of a surplus CGG triplet at the site of a seven times CGG repeat). We analysed the impact of this mutation on PTCH translation using a luciferase-based reporter vector. Insertion of an eighth CGG in the 5' UTR repressed protein translation dramatically when compared to the wild-type sequence. Our results suggest that this non-coding variant in the 5' UTR represents a mutation predisposing to basal cell carcinoma. PMID:24131384

  4. Polymorphisms and haplotypes in methylenetetrahydrofolate reductase gene and head and neck squamous cell carcinoma risk.

    PubMed

    Galbiatti, Ana Lívia Silva; Ruiz, Mariangela Torreglosa; Rodrigues, Juliana Olsen; Raposo, Luiz Sérgio; Maníglia, José Victor; Pavarino, Érika Cristina; Goloni-Bertollo, Eny Maria

    2012-01-01

    Functional polymorphisms in genes encoding enzymes involved in folate metabolism might modulate head and neck carcinoma risk because folate participates in DNA methylation and synthesis. We therefore conducted a case-control study of 853 individuals (322 head and neck cancer cases and 531 non-cancer controls) to investigate associations among MTHFR C677T and MTHFR A1298C polymorphisms and head and neck squamous cell carcinoma risk. Interactions between these two polymorphisms and risk factors and clinical histopathological parameters were also evaluated. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to genotype the polymorphisms and Chi-square test and multiple logistic regression were used for statistical analyses. The variables age?49 years, male gender, tobacco habits and alcohol consumption, MTHFR 1298 AC or CC genotypes, combined genotypes with two or more polymorphic alleles and 677T and 1298C polymorphic alleles were associated with increased risk for this disease (P<0.05). Furthermore, we found that 1298 AC or CC genotypes were associated with age?49 years, tobacco and alcohol habits (P<0.05). Regarding clinical histopathological parameters, the A1298C polymorphism was more frequent in patients with oral cavity as primary site (P<0.05). MTHFR polymorphisms may contribute for increase risk for head and neck carcinoma and the variables age?49 years, male gender, tobacco and alcohol habits were associated with MTHFR 1298AC or CC genotypes, confirming that individuals with these variables and MTHFR A1298C polymorphism has higher risk for this disease. PMID:21556759

  5. The association between methylene-tetrahydrofolate reductase gene polymorphism and lung cancer risk.

    PubMed

    Arslan, Sulhattin; Karadayi, Sule; Yildirim, Malik Ejder; Ozdemir, Ozturk; Akkurt, Ibrahim

    2011-02-01

    This study aimed to determine the relation between methylene-tetrahydrofolate reductase (MTHFR) gene polymorphism and lung cancer risk and the frequency of this polymorphism. The study involved 64 lung cancer patients (the study group) with definitive diagnosis and 61 noncancerous subjects (the control group). MTHFR C677T and A1298C mutation analysis was made using DNA isolated from peripheric blood and multiplex PCR and reverse hybridization strip test. Eighty-four percent of the patients were male. The age, gender, and history of alcohol use of the patients and control group were statistically similar. While MTHFR 677T and 677C allele frequency was 0.33 and 0.67 in the patients respectively, it was 0.29 and 0.71 in the control group. The frequencies of MTHFR 1298C and 1298A were 0.33 and 0.67 in the patients, and it was 0.31 and 0.69 in the control group respectively. When MTHFR 677TT and 677CT genotypes were compared with 677CC genotype, lung cancer risk was 2.4 times higher in the 677TT genotype. When MTHFR 1298AC and 1298CC genotypes were compared with 1298AA genotype, lung cancer risk was 1.5 times higher in 1298CC genotype. According to the results, allele frequency of homozygote T and C was high in lung cancer patients. It was 3.05 and 1.29 times higher in smokers than in non-smokers, and 3.05 and 1.64 times higher in males than in females; 3.0 and 2.44 times higher in those with non-small cell lung cancer than in those with small-cell lung cancer. PMID:20532637

  6. Association between MTHFR C677T and A1298C Polymorphisms and NSCL/P Risk in Asians: A Meta-Analysis

    PubMed Central

    Zhao, Mengmeng; Ren, Yangwu; Shen, Li; Zhang, Yue; Zhou, Baosen

    2014-01-01

    Objective Several studies have reported the association between methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and nonsyndromic cleft lip with or without palate (NSCL/P) in Asian populations. However, findings have been conflicting. In order to investigate the association, a meta-analysis was performed. Methods We searched Pubmed, MedLine and EmBase database to selected eligible studies. The pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated using fixed effects model or random effects model to assess the association between MTHFR polymorphisms and NSCL/P in both Asian children and mothers. Results Finally, nine case-control studies were included. Overall, the MTHFR C677T polymorphism and NSCL/P showed pooled ORs (95%CI) of 1.41(1.23–1.61) in Asian children, and 1.70(1.19–2.42) in Asian mothers. Subgroup analyses by geographical locations further identified the association in Eastern Asian children, Western/Central Asian children and mothers, but not in Eastern Asian mothers. However, no significant relationship between MTHFR A1298C polymorphism and NSCL/P was found in this meta-analysis. Conclusions The MTHFR 677T allele was associated with an increased risk of NSCL/P in Asian populations. PMID:24658649

  7. Prevalence of thromogenic gene mutations in women with recurrent miscarriage: A retrospective study of 1,507 patients

    PubMed Central

    Hilali, Nese Gul; Camuzcuoglu, Aysun; Camuzcuoglu, Hakan; Akbas, Halit; Kilic, Avni; Vural, Mehmet

    2014-01-01

    Objective Thromogenic gene mutations has been thought to be associated with recurrent pregnancy loss in women in Turkey. The aim of this study was to investigate the prevalence of thromogenic gene mutations such as factor V Leiden (FVL, G1691T), prothrombin (G20210A), and the methylene tetrahydrofolate reductase (MTHFR, C677T) mutation in women with recurrent pregnancy loss. Methods This descriptive study was carried out in the Department of Obstetrics and Gynaecology, Harran University School of Medicine, and included a total of 1,507 women with histories of recurrent pregnancy loss between January 2010 and June 2013. The mutations were assessed by using the polymerase chain reaction. Results The homozygous mutation frequencies of FVL, prothrombin, and MTHFR were found to be 3 (0.20%), 0 and 125 (8.29%), and the heterozygous mutation frequencies were 83 (5.51%), 61 (4.05%), and 612 (40.61%), respectively. Among the 86 FVL mutation patients, 38 also had accompanying prothrombin and MTHFR mutations. Conclusion Since the homozygous forms of the FVL-prothrombin gene mutations have low incidences and MTHFR mutation is similar to a healthy population, preconceptional thromogenic gene mutations screening seems to be controversial. PMID:25469341

  8. CTCF haploinsufficiency destabilizes DNA methylation and predisposes to cancer

    PubMed Central

    Kemp, Christopher J.; Moore, James M.; Moser, Russell; Bernard, Brady; Teater, Matt; Smith, Leslie E.; Rabaia, Natalia; Gurley, Kay E.; Guinney, Justin; Busch, Stephanie E.; Shaknovich, Rita; Lobanenkov, Victor V.; Liggitt, Denny; Shmulevich, Ilya; Melnick, Ari; Filippova, Galina N.

    2014-01-01

    SUMMARY Epigenetic alterations, particularly in DNA methylation, are ubiquitous in cancer, yet the molecular origins and the consequences of these alterations are poorly understood. The DNA binding protein CTCF regulates a diverse array of epigenetic processes and is frequently altered by hemizygous deletion or mutation in human cancer. To date, a causal role for CTCF in cancer has not been established. Here we show that Ctcf hemizygous knockout mice are markedly susceptible to spontaneous, radiation, and chemically induced cancer in a broad range of tissues. Ctcf+/? tumors are characterized by increased aggressiveness including invasion, metastatic dissemination, and mixed epithelial/mesenchymal differentiation. Molecular analysis of Ctcf+/? tumors indicates that Ctcf is haploinsufficient for tumor suppression. Tissues with hemizygous loss of CTCF exhibit increased variability in CpG methylation genome-wide. These findings establish CTCF as a prominent tumor suppressor gene and point to CTCF mediated epigenetic stability as a major barrier to neoplastic progression. PMID:24794443

  9. CTCF haploinsufficiency destabilizes DNA methylation and predisposes to cancer.

    PubMed

    Kemp, Christopher J; Moore, James M; Moser, Russell; Bernard, Brady; Teater, Matt; Smith, Leslie E; Rabaia, Natalia A; Gurley, Kay E; Guinney, Justin; Busch, Stephanie E; Shaknovich, Rita; Lobanenkov, Victor V; Liggitt, Denny; Shmulevich, Ilya; Melnick, Ari; Filippova, Galina N

    2014-05-22

    Epigenetic alterations, particularly in DNA methylation, are ubiquitous in cancer, yet the molecular origins and the consequences of these alterations are poorly understood. CTCF, a DNA-binding protein that regulates higher-order chromatin organization, is frequently altered by hemizygous deletion or mutation in human cancer. To date, a causal role for CTCF in cancer has not been established. Here, we show that Ctcf hemizygous knockout mice are markedly susceptible to spontaneous, radiation-, and chemically induced cancer in a broad range of tissues. Ctcf(+/-) tumors are characterized by increased aggressiveness, including invasion, metastatic dissemination, and mixed epithelial/mesenchymal differentiation. Molecular analysis of Ctcf(+/-) tumors indicates that Ctcf is haploinsufficient for tumor suppression. Tissues with hemizygous loss of CTCF exhibit increased variability in CpG methylation genome wide. These findings establish CTCF as a prominent tumor-suppressor gene and point to CTCF-mediated epigenetic stability as a major barrier to neoplastic progression. PMID:24794443

  10. Polymorphisms in genes involved in folate metabolism and colorectal neoplasia: a HuGE review.

    PubMed

    Sharp, Linda; Little, Julian

    2004-03-01

    Epidemiologic and mechanistic evidence suggests that folate is involved in colorectal neoplasia. Some polymorphic genes involved in folate metabolism--methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MTR A2756G), methionine synthase reductase (MTRR A66G), cystathionine beta-synthase (CBS exon 8, 68-base-pair insertion), and thymidylate synthase (TS enhancer region and 3' untranslated region)--have been investigated in colorectal neoplasia. For MTHFR C677T and A1298C, the variant allele is associated with reduced enzyme activity in vitro. For the other polymorphisms, functional data are limited and/or inconsistent. Genotype frequencies for all of the polymorphisms show marked ethnic and geographic variation. In most studies, MTHFR 677TT (10 studies, >4,000 cases) and 1298CC (four studies, >1,500 cases) are associated with moderately reduced colorectal cancer risk. In four of five genotype-diet interaction studies, 677TT subjects who had higher folate levels (or a "high-methyl diet") had the lowest cancer risk. In two studies, 677TT homozygote subjects with the highest alcohol intake had the highest cancer risk. Findings from six studies of MTHFR C677T and adenomatous polyps are inconsistent. There have been only one or two studies of the other polymorphisms; replication is needed. Overall, the roles of folate-pathway genes, folate, and related dietary factors in colorectal neoplasia are complex. Research priorities are suggested. PMID:14977639

  11. Glutamatergic synapse protein composition of wild-type mice is sensitive to in utero MTHFR genotype and the timing of neonatal vigabatrin exposure.

    PubMed

    Zuckerman, Chava; Blumkin, Elinor; Melamed, Osnat; Golan, Hava M

    2015-10-01

    The enzyme methylenetetrahydrofolate-reductase (MTHFR) is part of the homocysteine and folate metabolic pathways. In utero, Mthfr-deficient environment has been reported as a risk factor for neurodevelopmental disorders such as autism and neural tube defects. Neonatal disruption of the GABAergic system is also associated with behavioral outcomes. The interaction between Mthfr deficiency and neonatal exposure to the GABA-potentiating drug vigabatrin (GVG) in mice alters anxiety, memory, and social behavior in a gender-dependent manner. In addition, a gender-dependent enhancement of proteins implicated in excitatory synapse plasticity in the cerebral cortex was shown. Here we show that in utero MTHFR deficiency is sufficient to alter the levels of glutamate receptor subunits GluR1, GluR2, and NR2B in the cerebral cortex and hippocampus of adult offspring with a WT genotype. In addition, FMRP1, CAMKII α and γ, and NLG1 levels in WT offspring were vulnerable to the in utero genotype. These effects depend on brain region and the cellular compartment tested. The effect of in utero MTHFR deficiency varies with the age of neonatal GVG exposure to modify GluR1, NR2A, reelin, CAMKII α, and NLG1 levels. These changes in molecular composition of the glutamatergic synapse were associated with increased anxiety-like behavior. Complex, multifactorial disorders of the nervous system show significant association with several genetic and environmental factors. Our data exemplify the contribution of an in utero MTHFR-deficient environment and early exposure to an antiepileptic drug to the basal composition of the glutamatergic synapses. The robust effect is expected to alter synapse function and plasticity and the cortico-hippocampal circuitry. PMID:26235956

  12. Phosphodiesterase sequence variants may predispose to prostate cancer.

    PubMed

    de Alexandre, Rodrigo B; Horvath, Anelia D; Szarek, Eva; Manning, Allison D; Leal, Leticia F; Kardauke, Fabio; Epstein, Jonathan A; Carraro, Dirce M; Soares, Fernando A; Apanasovich, Tatiyana V; Stratakis, Constantine A; Faucz, Fabio R

    2015-08-01

    We hypothesized that mutations that inactivate phosphodiesterase (PDE) activity and lead to increased cAMP and cyclic guanosine monophosphate levels may be associated with prostate cancer (PCa). We sequenced the entire PDE coding sequences in the DNA of 16 biopsy samples from PCa patients. Novel mutations were confirmed in the somatic or germline state by Sanger sequencing. Data were then compared to the 1000 Genome Project. PDE, CREB and pCREB protein expression was also studied in all samples, in both normal and abnormal tissue, by immunofluorescence. We identified three previously described PDE sequence variants that were significantly more frequent in PCa. Four novel sequence variations, one each in the PDE4B,PDE6C, PDE7B and PDE10A genes, respectively, were also found in the PCa samples. Interestingly, PDE10A and PDE4B novel variants that were present in 19 and 6% of the patients were found in the tumor tissue only. In patients carrying PDE defects, there was pCREB accumulation (P<0.001), and an increase of the pCREB:CREB ratio (patients 0.97±0.03; controls 0.52±0.03; P-value <0.001) by immunohistochemical analysis. We conclude that PDE sequence variants may play a role in the predisposition and/or progression to PCa at the germline and/or somatic state respectively. PMID:25979379

  13. Management of genetic syndromes predisposing to gynecologic cancers.

    PubMed

    Miesfeldt, Susan; Lamb, Amanda; Duarte, Christine

    2013-03-01

    Women with personal and family histories consistent with gynecologic cancer-associated hereditary cancer susceptibility disorders should be referred for genetic risk assessment and counseling. Genetic counseling facilitates informed medical decision making regarding genetic testing, screening, and treatment, including chemoprevention and risk-reducing surgery. Because of limitations of ovarian cancer screening, hereditary breast and ovarian cancer-affected women are offered risk-reducing bilateral salpingo-oophorectomy (BSO) between ages 35 and 40 years, or when childbearing is complete. Women with documented Lynch syndrome, associated with mutations in mismatch repair genes, should be screened at a young age and provided prevention options, including consideration of risk-reducing total abdominal hysterectomy and BSO, as well as intensive gastrointestinal screening. Clinicians caring for high-risk women must consider the potential adverse ethical, legal, and social issues associated with hereditary cancer risk assessment and testing. Additionally, at-risk family members should be alerted to their cancer risks, as well as the availability of risk assessment, counseling, and treatment services. PMID:23315239

  14. Developmental Estrogen Exposures Predispose to Prostate Carcinogenesis with Aging

    PubMed Central

    Prins, Gail S.; Birch, Lynn; Tang, Wan-Yee; Ho, Shuk-Mei

    2007-01-01

    Prostate morphogenesis occurs in utero in humans and during the perinatal period in rodents. While largely driven by androgens, there is compelling evidence for a permanent influence of estrogens on prostatic development. If estrogenic exposures are abnormally high during the critical developmental period, permanent alterations in prostate morphology and function are observed, a process referred to as developmental estrogenization. Using the neonatal rodent as an animal model, it has been shown that early exposure to high doses of estradiol results in an increased incidence of prostatic lesions with aging which include hyperplasia, inflammatory cell infiltration and prostatic intraepithelial neoplasia or PIN, believed to be the precursor lesion for prostatic adenocarcinoma. The present review summarizes research performed in our laboratory to characterize developmental estrogenization and identify the molecular pathways involved in mediating this response. Furthermore, recent studies performed with low-dose estradiol exposures during development as well as exposures to environmentally relevant doses of the endocrine disruptor bisphenol A show increased susceptibility to PIN lesions with aging following additional adult exposure to estradiol. Gene methylation analysis revealed a potential epigenetic basis for the estrogen imprinting of the prostate gland. Taken together, our results suggest that a full range of estrogenic exposures during the postnatal critical period – from environmentally relevant bisphenol A exposure to low-dose and pharmacologic estradiol exposures – results in an increased incidence and susceptibility to neoplastic transformation of the prostate gland in the aging male which may provide a fetal basis for this adult disease. PMID:17123779

  15. Genome-Wide Association Study of Golden Retrievers Identifies Germ-Line Risk Factors Predisposing to Mast Cell Tumours

    PubMed Central

    Arendt, Maja L.; Melin, Malin; Tonomura, Noriko; Koltookian, Michele; Courtay-Cahen, Celine; Flindall, Netty; Bass, Joyce; Boerkamp, Kim; Megquir, Katherine; Youell, Lisa; Murphy, Sue; McCarthy, Colleen; London, Cheryl; Rutteman, Gerard R.; Starkey, Mike; Lindblad-Toh, Kerstin

    2015-01-01

    Canine mast cell tumours (CMCT) are one of the most common skin tumours in dogs with a major impact on canine health. Certain breeds have a higher risk of developing mast cell tumours, suggesting that underlying predisposing germ-line genetic factors play a role in the development of this disease. The genetic risk factors are largely unknown, although somatic mutations in the oncogene C-KIT have been detected in a proportion of CMCT, making CMCT a comparative model for mastocytosis in humans where C-KIT mutations are frequent. We have performed a genome wide association study in golden retrievers from two continents and identified separate regions in the genome associated with risk of CMCT in the two populations. Sequence capture of associated regions and subsequent fine mapping in a larger cohort of dogs identified a SNP associated with development of CMCT in the GNAI2 gene (p = 2.2x10-16), introducing an alternative splice form of this gene resulting in a truncated protein. In addition, disease associated haplotypes harbouring the hyaluronidase genes HYAL1, HYAL2 and HYAL3 on cfa20 and HYAL4, SPAM1 and HYALP1 on cfa14 were identified as separate risk factors in European and US golden retrievers, respectively, suggesting that turnover of hyaluronan plays an important role in the development of CMCT. PMID:26588071

  16. High prevalence of hyperhomocysteinemia in chronic alcoholism: the importance of the thermolabile form of the enzyme methylenetetrahydrofolate reductase (MTHFR).

    PubMed

    de la Vega, M J; Santolaria, F; González-Reimers, E; Alemán, M R; Milena, A; Martínez-Riera, A; González-García, C

    2001-10-01

    Alcoholism is related to malnutrition and low levels of several vitamins that take part in the metabolism of homocysteine. The objective of the study was to analyze the prevalence of hyperhomocysteinemia in patients with heavy alcohol intake and the factors on which it depends. Included in the study were 103 hospitalized heavy drinkers (i.e., patients with an intake of alcohol greater than 80 g per day). Serum homocysteine, folate, and vitamin B(12) levels, plasma vitamin B(6) levels, and CT677 polymorphisms of methylenetetrahydrofolate reductase (MTHFR) were determined. We also recorded the intensity of alcoholism, the status of nutrition, and the existence of liver cirrhosis. Determination of biochemical data was repeated after 15 days of withdrawal. Serum homocysteine levels were found to be significantly elevated, whereas serum folate and plasma B(6) levels were significantly decreased. Serum homocysteine levels were significantly higher in those heavy drinkers who showed the TT polymorphism of MTHFR, with a prevalence of hyperhomocysteinemia of 84.2% in the homozygote TT, 54.3% in the heterozygote CT, and 31.6% in the normal CC genotype. Serum homocysteine inversely correlated with serum folate, serum B(12), and plasma B(6) levels. We did not find any relation between serum homocysteine and intensity of alcoholism, nutritional status, or liver cirrhosis. Serum folate levels were significantly decreased in heavy drinkers, mainly depending on irregular feeding and malnutrition. After 15 days of withdrawal, serum homocysteine levels significantly decreased, whereas folate, B(12), and B(6) levels significantly increased. The conclusion is that heavy drinkers show a high prevalence of hyperhomocysteinemia related to low levels of folate, B(6), and B(12) and to the TT polymorphism of MTHFR. PMID:11747974

  17. Association between the MTHFR C677T polymorphism and risk of cancer: evidence from 446 case-control studies.

    PubMed

    Xie, Shu-Zhe; Liu, Zhi-Zhong; Yu, Jun-hua; Liu, Li; Wang, Wei; Xie, Dao-Lin; Qin, Jiang-Bo

    2015-11-01

    Many molecular epidemiological studies have been performed to explore the association between MTHFR C677T polymorphism and cancer risk in diverse populations. However, the results were inconsistent. Hence, we performed a meta-analysis to investigate the association between cancer risk and MTHFR C677T (150,086 cases and 200,699 controls from 446 studies) polymorphism. Overall, significantly increased cancer risk was found when all eligible studies were pooled into the meta-analysis. In the further stratified and sensitivity analyses, significantly increased breast cancer risk was found in Asians and Indians, significantly decreased colon cancer risk was found, significantly decreased colorectal cancer risk was found in male population, significantly increased gastric cancer risk was found in Caucasians and Asians, significantly increased hepatocellular cancer risk was found in Asians, significantly decreased adult acute lymphoblastic leukemia (AALL) risk was found in Caucasians, significantly decreased childhood acute lymphoblastic leukemia (CALL) risk was found in Asians, and significantly increased multiple myeloma and NHL risk was found in Caucasians. In summary, this meta-analysis suggests that MTHFR C677T polymorphism is associated with increased breast cancer, gastric cancer, and hepatocellular cancer risk in Asians, is associated with increased gastric cancer, multiple myeloma, and NHL risk in Caucasians, is associated with decreased AALL risk in Caucasians, is associated with decreased CALL risk in Asians, is associated with increased breast cancer risk in Asians, is associated with decreased colon cancer risk, and is associated with decreased colorectal cancer risk in male population. Moreover, this meta-analysis also points out the importance of new studies, such as Asians of HNC, Asians of lung cancer, and Indians of breast cancer, because they had high heterogeneity in this meta-analysis (I(2) > 75%). PMID:26081619

  18. The MTHFR 677C-->T polymorphism and behaviors in children with autism: exploratory genotype-phenotype correlations.

    PubMed

    Goin-Kochel, Robin P; Porter, Anne E; Peters, Sarika U; Shinawi, Marwan; Sahoo, Trilochan; Beaudet, Arthur L

    2009-04-01

    New evidence suggests that autism may be associated with (a) varied behavioral responses to folate therapy and (b) metabolic anomalies, including those in folate metabolism, that contribute to hypomethylation of DNA. We hypothesized that children with autism who are homozygous for the MTHFR 677 T allele (TT) and, to a lesser extent those with the CT variant, would exhibit more behavioral problems and/or more severe problematic behaviors than homozygous wild-type (CC) individuals because of difficulties in effectively converting 5,10-MTHF to 5-MTHF. Data from the Autism Genetic Resource Exchange (AGRE) collection were analyzed for all children who met strict criteria for autism per the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS) and who had been genotyped for the 677 C to T MTHFR polymorphism (n=147). Chi-square tests, logistic regression, and one-way ANOVAs were used to determine whether differences existed among MTHFR genotypes for specific behaviors on the ADI-R and indices for level of functioning. Exploratory results indicated four behaviors from the ADI-R that were more common and problematic (95% CI) among those with at least one copy of the T allele as compared to homozygous wild-type individuals: direct gaze, current complex body movements, a history of self-injurious behavior, and current overactivity (ORs=2.72, 2.33, 2.12, 2.47, respectively). No differences existed among genotypes for level of functioning as measured with the Peabody Picture Vocabulary Test-Third Edition, Ravens Colored Progressive Matrices, or the Vineland Adaptive Behavior Scales. Findings call for further investigation of the relationship between folate metabolism and problem behaviors among children with autism. PMID:19455642

  19. The Bipolar Association Case-Control Study (BACCS) and meta-analysis: No association with the 5,10-Methylenetetrahydrofolate reductase gene and bipolar disorder.

    PubMed

    Cohen-Woods, Sarah; Craig, Ian; Gaysina, Darya; Gray, Joanna; Gunasinghe, Cerisse; Craddock, Nick; Elkin, Amanda; Jones, Lisa; Kennedy, James; King, Nicole; Korszun, Ania; Knight, Jo; Owen, Michael; Parikh, Sagar; Strauss, John; Sterne, Abram; Tozzi, Federica; Perry, Julia; Muglia, Pierandrea; Vincent, John; McGuffin, Peter; Farmer, Anne

    2010-10-01

    Bipolar disorder (BD) is a complex genetic disease for which the underlying pathophysiology has yet to be fully explained. 5,10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in folate-mediated one-carbon metabolism and folate deficiency can be associated with psychiatric symptoms. A single base variant in MTHFR gene (C677T) results in the production of a mildly dysfunctional thermolabile enzyme and has recently been implicated in BD. We conducted an association study of this polymorphism in 897 patients with bipolar I or bipolar II disorder, and 1,687 healthy control subjects. We found no evidence for genotypic or allelic association in this sample. We also performed a meta-analysis of our own, and all published data, and report no evidence for association. Our findings suggest that the MTHFR C677T polymorphism is not involved in the genetic etiology of clinically significant BD. PMID:20552676

  20. Modeling gene-by-environment interaction in comorbid depression with alcohol use disorders via an integrated bioinformatics approach

    PubMed Central

    McEachin, Richard C; Keller, Benjamin J; Saunders, Erika FH; McInnis, Melvin G

    2008-01-01

    Background Comorbidity of Major Depressive Disorder (depression) and Alcohol Use Disorders (AUD) is well documented. Depression, AUD, and the comorbidity of depression with AUD show evidence of genetic and environmental influences on susceptibility. We used an integrated bioinformatics approach, mining available data in multiple databases, to develop and refine a model of gene-by-environment interaction consistent with this comorbidity. Methods We established the validity of a genetic model via queries against NCBI databases, identifying and validating TNF (Tumor Necrosis Factor) and MTHFR (Methylenetetrahydrofolate Reductase) as candidate genes. We used the PDG-ACE algorithm (Prioritizing Disease Genes by Analysis of Common Elements) to show that TNF and MTHFR share significant commonality and that this commonality is consistent with a response to environmental exposure to ethanol. Finally, we used MetaCore from GeneGo, Inc. to model a gene-by-environment interaction consistent with the data. Results TNF Alpha Converting Enzyme (TACE) activity is suppressed by ethanol exposure, resulting in reduced TNF signaling. TNF binds to TNF receptors, initiating signal transduction pathways that activate MTHFR expression. MTHFR is an essential enzyme in folate metabolism and reduced folate levels are associated with both AUD and depression. Integrating these pieces of information our model shows how excessive alcohol use would be expected to lead to reduced TNF signaling, reduced MTHFR expression, and increased susceptibility to depression. Conclusion The proposed model provides a novel hypothesis on the genetic etiology of comorbid depression with AUD, consistent with established clinical and biochemical data. This analysis also provides an example of how an integrated bioinformatics approach can maximize the use of available biomedical data to improve our understanding of complex disease. PMID:18822146

  1. Association of the C2-CFB locus with non-infectious uveitis, specifically predisposed to Vogt-Koyanagi-Harada disease.

    PubMed

    Yang, Mingming; Fan, Jiao-Jie; Wang, Jun; Zhao, Yan; Teng, Yan; Liu, Ping

    2016-04-01

    Complement component 2 (C2) and factor B (CFB) are regulators of complement system and involved in the alternative pathway, which have been identified to be associated with multiple immune-related diseases. This study aimed to investigate the association of these genes with non-infectious intermediate and posterior uveitis. A total of 260 Chinese non-infectious uveitis patients were recruited, including 97 patients with Vogt-Koyanagi-Harada disease (VKH), 70 patients with intermediate uveitis (IU) and 93 patients with Behçet's disease (BD). Two hundred and ninety-three normal control subjects were also recruited. Five SNPs across the C2/CFB region were selected and genotyped using TaqMan SNP Genotyping Assays. Association analysis was adjusted for gender and stratified by different subtypes. The CFB SNP rs1048709 was significantly associated with non-infectious uveitis [P corr = 0.01, OR 1.49 (allele model) and P corr = 0.04, OR 1.58 (dominant model), respectively], and similar association was also detected between rs1048709 and female uveitis patients (P corr = 0.01, OR 1.70 and P corr = 0.049, OR 184, respectively). Moreover, subgroup analyses showed that CFB-rs1048709 was specifically associated with VKH, where significantly higher frequencies of A allele and AA homozygosity were observed in VKH patients compared with controls (P corr = 0.025 and P corr = 0.035, respectively), whereas none of these five SNPs was associated with IU or BD. In addition, a haplotype block across CFB (GTG) was significantly predisposed to uveitis with protective effect (OR 0.66, P corr = 0.048). Our results revealed a significant association of CFB with non-infectious uveitis, particularly predisposed to VKH disease. Genetic differences for uveitis could be gender-specific. PMID:26671509

  2. Search for a gene predisposing to manic-depression on chromosome 21

    SciTech Connect

    Byerley, W.; Holik, J.; Hoff, M.; Coon, H.

    1995-06-19

    Six kindreds containing multiple cases of manic-depressive illness (MDI) were genotyped with seven highly polymorphic microsatellite loci used in the construction of an index map for chromosome 21. The kindreds were also genotyped with a microsatellite polymorphism for PFKL, a chromosome 21 locus that has shown suggestive linkage to MDI in one pedigree. Evidence of linkage was not found assuming either autosomal dominant or recessive inheritance. The nonparametric affected sib pair test did not yield significant evidence of linkage. 11 refs., 1 fig., 3 tabs.

  3. Naturally Occurring Mutations in the MPS1 Gene Predispose Cells to Kinase Inhibitor Drug Resistance.

    PubMed

    Gurden, Mark D; Westwood, Isaac M; Faisal, Amir; Naud, Sébastien; Cheung, Kwai-Ming J; McAndrew, Craig; Wood, Amy; Schmitt, Jessica; Boxall, Kathy; Mak, Grace; Workman, Paul; Burke, Rosemary; Hoelder, Swen; Blagg, Julian; Van Montfort, Rob L M; Linardopoulos, Spiros

    2015-08-15

    Acquired resistance to therapy is perhaps the greatest challenge to effective clinical management of cancer. With several inhibitors of the mitotic checkpoint kinase MPS1 in preclinical development, we sought to investigate how resistance against these inhibitors may arise so that mitigation or bypass strategies could be addressed as early as possible. Toward this end, we modeled acquired resistance to the MPS1 inhibitors AZ3146, NMS-P715, and CCT251455, identifying five point mutations in the kinase domain of MPS1 that confer resistance against multiple inhibitors. Structural studies showed how the MPS1 mutants conferred resistance by causing steric hindrance to inhibitor binding. Notably, we show that these mutations occur in nontreated cancer cell lines and primary tumor specimens, and that they also preexist in normal lymphoblast and breast tissues. In a parallel piece of work, we also show that the EGFR p.T790M mutation, the most common mutation conferring resistance to the EGFR inhibitor gefitinib, also preexists in cancer cells and normal tissue. Our results therefore suggest that mutations conferring resistance to targeted therapy occur naturally in normal and malignant cells and these mutations do not arise as a result of the increased mutagenic plasticity of cancer cells. PMID:26202014

  4. DIET- AND COLONIZATION-DEPENDENT INTESTINAL DYSFUNCTION PREDISPOSES TO NECROTIZING ENTEROCOLITIS IN PRETERM PIGS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND & AIMS: Preterm birth and formula feeding are key risk factors associated with necrotizing enterocolitis (NEC) in infants, but little is known about intestinal conditions that predispose to disease. Thus, structural, functional, and microbiologic indices were used to investigate the etiol...

  5. The Influence of Predisposing, Enabling and Need Factors on Condom Use in Ivory Coast

    ERIC Educational Resources Information Center

    Ngamini Ngui, Andre

    2010-01-01

    The main objective of this study was to identify key determinants of condom use in Ivory Coast. Data stem from Ivory Coast Demographic Health Survey (DHS) conducted by ORC Macro in 2005 among a representative sample of 9,686 persons aged 15 - 49. Following the behavioral model, we use logistic regression to assess the effect of predisposing,…

  6. Bilateral and Simultaneous Rupture of the Triceps Tendon in a Patient without Predisposing Factors

    PubMed Central

    Desai, Bobby; Slish, John; Allen, Brandon

    2012-01-01

    Tendon rupture is typically associated with predisposing features including renal failure, hyperparathyroidism, and connective tissue elastosis. We present a case in which none of these risk factors is present and in a completely healthy patient. To our knowledge, this has never been reported in the literature. PMID:23326731

  7. A Predisposing Factor for Spontaneous Choledochal Cyst Perforation: Esophageal Dilatation Procedures

    PubMed Central

    Doneray, Hakan; Seven, Bedri; Sepetcigil, Oguzhan; Salman, Ahmet Bedii; Orbak, Zerrin

    2009-01-01

    Cyst rupture is one of the rarest complications of choledochal cysts (CC). We report an 8-year-old boy with CC rupture leading to bile peritonitis following repeated esophageal dilatations for corrosive stricture, and discuss how the esophageal dilatation procedures might constitute a predisposing factor for CC perforation. PMID:25610066

  8. Gene polymorphism and folate metabolism: a maternal risk factor for Down syndrome.

    PubMed

    Sheth, Jayesh J; Sheth, Frenny J

    2003-02-01

    The high birth frequency of Down syndrome (DS), trisomy 21 (T21), has been a subject of interest to the clinicians and researchers due to its complexity in phenotypic expression. In addition to the maternal age, identification of the mechanistic basis for T21 requires an understanding of the cellular-molecular events and other biochemical pathways that could promote maternal meiotic nondisjunction. Recent studies have linked the increased frequency of polymorphism of methylenetetrahydrofolate reductase (MTHFR, C677T) and methionine synthase gene (MTRR, A66G) in mothers with DS child. Based on evidence that abnormal folate and methyl metabolism can lead to DNA hypomethylation and abnormal chromosomal segregation, researchers have observed that mothers with mutation in MTHFR (C677T) and MTRR (A66G) gene have elevated levels of plasma homocysteine. This was found to be associated with a 2.6 to 2.9 fold increased risk of having child with DS compared to mothers without the mutation. Subsequent studies evaluating Italian, Irish, French, and Indian-Gujarati women could not demonstrate an association of MTHFR gene polymorphism in mothers with DS child. However, the Irish study did find an increased risk of DS associated with the MTRR polymorphism and an interactive effect of MTRR and MTHFR polymorphisms with increased risk. Interestingly, an increase in plasma homocysteine was found to be a risk factor for DS in several of the studies. Despite the differences, the published studies suggest a common theme of abnormal folate metabolism associated with increased risk of having a child with DS. These observations suggest that there seems to be a geographic variation in gene polymorphism and it could not be attributable to meiotic nondysjunction in all mothers with DS child but increased homocysteine in all different study group does suggest that there may be a gene-nutritional or gene-gene or gene-nutritional-environmental factors involved in increased frequency of meiotic nondisjunction which needs transnational and multinational study design. PMID:12626825

  9. High dose methotrexate treatment in childhood ALL: pilot study on the impact of the MTHFR 677C>T and 1298A>C polymorphisms on MTX-related toxicity.

    PubMed

    Haase, R; Elsner, K; Merkel, N; Stiefel, M; Mauz-Körholz, C; Kramm, C M; Körholz, D

    2012-04-01

    Methotrexate (MTX) is commonly administered in high doses for treatment of childhood acute lymphoblastic leukemia (ALL). The aim of this analysis was to study the influence of 2 common MTHFR polymorphisms (MTHFR 677C>T and 1298 A>C) on MTX toxicity in children with ALL.Retrospective analysis of 129 MTX courses in 34 pediatric patients with ALL.677C>T variants (CT or TT) were found in 19 (14 heterozygous, 5 homozygous) and 1298A>C variants (AC or CC) in 20 (16 heterozygous, 4 homozygous) patients. The MTHFR 677C>T wild type was associated with an increased frequency of grade III and IV leukopenia (60% vs. 31%, p<0.05) compared to the variants. The rate of severe infections (21% vs. 0%, p<0.05) and grade III-IV anemia (26% vs. 5%, p<0.05) was increased in carriers of the MTHFR 677C>T wild type compared to patients with the TT variant. Grade III-IV anemia was more frequent in patients with the MTHFR 1298A>C CC variant compared to the wild type (56% vs. 21%, p<0.05). The differences were not significant in a patient-based analysis.MTX related toxicity might be influenced by the MTHFR 677C>T or the MTHFR 1298A>C polymorphisms. Differences in MTX toxicity are only partially explainable by these 2 polymorphisms. PMID:22513795

  10. MTHFR deficiency or reduced intake of folate or choline in pregnant mice results in impaired short-term memory and increased apoptosis in the hippocampus of wild-type offspring.

    PubMed

    Jadavji, N M; Deng, L; Malysheva, O; Caudill, M A; Rozen, R

    2015-08-01

    Genetic or nutritional disturbances in one-carbon metabolism, with associated hyperhomocysteinemia, can result in complex disorders including pregnancy complications and neuropsychiatric diseases. In earlier work, we showed that mice with a complete deficiency of methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate and homocysteine metabolism, had cognitive impairment with disturbances in choline metabolism. Maternal demands for folate and choline are increased during pregnancy and deficiencies of these nutrients result in several negative outcomes including increased resorption and delayed development. The goal of this study was to investigate the behavioral and neurobiological impact of a maternal genetic deficiency in MTHFR or maternal nutritional deficiency of folate or choline during pregnancy on 3-week-old Mthfr(+/+) offspring. Mthfr(+/+) and Mthfr(+/-) females were placed on control diets (CD); and Mthfr(+/+) females were placed on folate-deficient diets (FD) or choline-deficient diets (ChDD) throughout pregnancy and lactation until their offspring were 3weeks of age. Short-term memory was assessed in offspring, and hippocampal tissue was evaluated for morphological changes, apoptosis, proliferation and choline metabolism. Maternal MTHFR deficiency resulted in short-term memory impairment in offspring. These dams had elevated levels of plasma homocysteine when compared with wild-type dams. There were no differences in plasma homocysteine in offspring. Increased apoptosis and proliferation was observed in the hippocampus of offspring from Mthfr(+/-) mothers. In the maternal FD and ChDD study, offspring also showed short-term memory impairment with increased apoptosis in the hippocampus; increased neurogenesis was observed in ChDD offspring. Choline acetyltransferase protein was increased in the offspring hippocampus of both dietary groups and betaine was decreased in the hippocampus of FD offspring. Our results reveal short-term memory deficits in the offspring of dams with MTHFR deficiency or dietary deficiencies of critical methyl donors. We suggest that deficiencies in maternal one-carbon metabolism during pregnancy can contribute to hippocampal dysfunction in offspring through apoptosis or altered choline metabolism. PMID:25956258

  11. Deleterious RAD51C germline mutations rarely predispose to breast and ovarian cancer in Pakistan.

    PubMed

    Rashid, Muhammad U; Muhammad, Noor; Faisal, Saima; Amin, Asim; Hamann, Ute

    2014-06-01

    RAD51C plays a key role in homologous recombination-mediated DNA repair and maintenance of genomic stability. Biallelic RAD51C mutations cause Fanconi anemia, and monoallelic mutations predispose women to breast and ovarian cancer. Genetic variability of RAD51C and its impact in Asian populations have been poorly studied. Here, we report the results of comprehensive mutational screening of the RAD51C gene in 348 BRCA1/2-negative breast and/or ovarian cancer patients from Pakistan. Mutation analysis of the complete RAD51C-coding region was performed using denaturing high-performance liquid chromatography analysis, followed by DNA sequencing of variant fragments. Three novel protein-truncating mutations, c.204T>A, c.225T>G, and c.701C>G, were identified. c.204T>A was found in one out of 22 (4.5 %) early-onset (?45 years of age) ovarian cancer patients and c.225T>G in one out of 119 (0.8 %) patients from breast cancer only families. c.701C>G was found in a 60-year-old control with no family history of breast/ovarian cancer. Furthermore, three novel in silico-predicted potentially functional mutations, a missense mutation, c.873T>G, a variant in 5'UTR, c.1-34T>G, and a recurrent intronic variant, c.965+21A>G, were identified. The missense mutation was observed in a patient with bilateral breast cancer from a breast and ovarian cancer family (HBOC), the 5'UTR variant was noted in an early-onset breast cancer patient, and the intronic variant in one early-onset breast cancer patient and one ovarian cancer patient from a HBOC family. Five of the six mutations described were not detected in 400 healthy controls. These findings suggest that RAD51C plays a marginal role in breast and ovarian cancer predisposition in Pakistan. Reliable estimation of the clinical implications of carrying a deleterious RAD51C mutation will require identification of additional mutation-positive patients/families. PMID:24800917

  12. Impact of thrombophilic genes mutations on thrombosis risk in Egyptian nonmetastatic cancer patients.

    PubMed

    Wahba, Mona Ahmed; Ismail, Mona Ahmed; Saad, Abeer Attia; Habashy, Deena Mohamed; Hafeez, Zeinab Mohamed Abdel; Boshnak, Noha Hussein

    2015-04-01

    Venous thromboembolism (VTE) is a common complication in cancer patients. Several genetic risk factors related to thrombophilia are known; however, their contributions to thrombotic tendency in cancer patients have conflicting results. We aimed to determine the prevalence of factor V Leiden (FVL), prothrombin (PTH) G20210A and methylene tetrahydrofolate reductase (MTHFR) C677T gene polymorphisms in Egyptian nonmetastatic cancer patients and their influence on thrombosis risk in those patients. Factor V Leiden, PTH G20210A and MTHFR C677T polymorphisms were detected in 40 cancer patients with VTE (group 1) and 40 cancer patients with no evidence of VTE (group 2) by PCR-based DNA analysis. Factor V and MTHFR mutations were higher in group 1 than in group 2 (factor V heterozygous mutation: 20 vs. 7.5%, homozygous mutation: 10 vs. 2.5%; MTHFR heterozygous mutation: 40 vs. 25%, homozygous mutation 5 vs. 0%, respectively) (P?=?0.03). Mortality rate was higher in group 1 (75%) than in group 2 (25%; P?gene mutations worsened the overall survival (P?=?0.0003). Cox regression proved that both thrombosis and presence of factor V mutation are independent factors affecting survival in cancer patients (P?MTHFR mutations and risk of VTE in Egyptian cancer patients. Thrombosis and presence of factor V mutation are independent factors that influence survival in those patients. PMID:25565385

  13. Polymorphisms of Genes Involved in the Folate Metabolic Pathway Impact the Occurrence of Unexplained Recurrent Pregnancy Loss.

    PubMed

    Luo, Li; Chen, Yueming; Wang, Li; Zhuo, Guangchao; Qiu, Chunning; Tu, Qiaofeng; Mei, Jin; Zhang, Wen; Qian, Xia; Wang, Xianjun

    2015-07-01

    Low levels of folate combined with high levels of homocysteine may cause unexplained recurrent pregnancy loss (URPL). However, the relationships between polymorphisms in genes of the folate metabolic pathway and URPL remain controversial. We conducted a case-control study to explore polymorphisms of the major folate pathway genes, including methylenetetrahydrofolate reductase (MTHFR) 677C>T, MTHFR 1298A>C, methionine synthase (MTR) 2756A>G, methionine synthase reductase (MTRR) 66A>G and reduced folate carrier 1 (RFC-1) 80A>G, and their associations with URPL. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the distributions of MTHFR, MTR and RFC-1 polymorphisms, and the results were validated using direct sequencing. The polymorphisms in MTRR were determined using direct sequencing. Haplotypes were analyzed using SHEsis, an online tool for biological analysis. We found that the MTHFR 677T allele and the 677T/1298A/2756A/66A/80G haplotype were risk factors for URPL, while the MTR 2756G allele and the 677C/1298A/2756A/66A/80A haplotype exhibited protective effects on susceptibility to URPL in a Chinese Han population from the Hangzhou area. PMID:25544674

  14. Seven novel mutations in the methylenetetrahydrofolate reductase gene and genotype/phenotype correlations in severe methylenetetrahydrofolate reductase deficiency

    SciTech Connect

    Goyette, P.; Frosst, P.; Rosenblatt, D.S.; Rozen. R.

    1995-05-01

    5-Methyltetrahydrofolate, the major form of folate in plasma, is a carbon donor for the remethylation of homocysteine to methionine. This form of folate is generated from 5,10-methylenetetrahydrofolate through the action of 5,10-methylenetetrahydrofolate reductase (MTHFR), a cytosolic flavoprotein. Patients with an autosomal recessive severe deficiency of MTHFR have homocystinuria and a wide range of neurological and vascular disturbances. We have recently described the isolation of a cDNA for MTHFR and the identification of two mutations in patients with severe MTHFR deficiency. We report here the characterization of seven novel mutations in this gene: six missense mutations and a 5{prime} splice-site defect that activates a cryptic splice in the coding sequence. We also present a preliminary analysis of the relationship between genotype and phenotype for all nine mutations identified thus far in this gene. A nonsense mutation and two missense mutations (proline to leucine and threonine to methionine) in the homozygous state are associated with extremely low activity (0%-3%) and onset of symptoms within the 1st year of age. Other missense mutations (arginine to cysteine and arginine to glutamine) are associated with higher enzyme activity and later onset of symptoms. 19 refs., 4 figs., 2 tabs.

  15. Association of neural tube defects in children of mothers with MTHFR 677TT genotype and abnormal carbohydrate metabolism risk: a case-control study.

    PubMed

    Cadenas-Benitez, N M; Yanes-Sosa, F; Gonzalez-Meneses, A; Cerrillos, L; Acosta, D; Praena-Fernandez, J M; Neth, O; Gomez de Terreros, I; Ybot-González, P

    2014-01-01

    Abnormalities in maternal folate and carbohydrate metabolism have both been shown to induce neural tube defects (NTD) in humans and animal models. However, the relationship between these two factors in the development of NTDs remains unclear. Data from mothers of children with spina bifida seen at the Unidad de Espina Bífida del Hospital Infantil Virgen del Rocío (case group) were compared to mothers of healthy children with no NTD (control group) who were randomly selected from patients seen at the outpatient ward in the same hospital. There were 25 individuals in the case group and 41 in the control group. Analysis of genotypes for the methylenetetrahydrofolate reductase (MTHFR) 677CT polymorphism in women with or without risk factors for abnormal carbohydrate metabolism revealed that mothers who were homozygous for the MTHFR 677TT polymorphism and at risk of abnormal carbohydrate metabolism were more likely to have offspring with spina bifida and high levels of homocysteine, compared to the control group. The increased incidence of NTDs in mothers homozygous for the MTHFR 677TT polymorphism and at risk of abnormal carbohydrate metabolism stresses the need for careful metabolic screening in pregnant women, and, if necessary, determination of the MTHFR 677CT genotype in those mothers at risk of developing abnormal carbohydrate metabolism. PMID:24737468

  16. Association between MTHFR C677T Polymorphism and Risk of Acute Lymphoblastic Leukemia: A Meta-Analysis Based on 51 Case-Control Studies

    PubMed Central

    Li, Su-yi; Ye, Jie-yu; Liang, En-yu; Zhou, Li-xia; Yang, Mo

    2015-01-01

    Background Studies and systematic reviews have reached inconsistent conclusions on the role of 5, 10-methylenetetrahydrofolate reductase (MTHFR) polymorphism C677T in acute lymphoblastic leukemia (ALL) risk. Material/Methods The present meta-analysis comprising of 51 case-control studies, including 7892 cases and 14 280 controls was performed to reevaluate the association between MTHFR C677T polymorphism and ALL risk. Results Statistical differences were found in the dominant model (TT+CT vs. CC, odd ratio (OR)=0.89, 95% CI, 0.79–1.00, P=0.04) and the CT vs. CC (OR=0.89, 95% CI, 0.80–1.00, P=0.05), but not in the allele contrast model (T vs. C, OR=0.92, 95% CI, 0.84–1.01, P=0.08), additive model (TT vs. CC, OR=0.87, 95% CI, 0.73–1.05, P=0.15), or recessive model (TT vs. CT+CC, OR=0.94, 95% CI, 0.81–1.10, P=0.44) in overall populations. In the subgroup analyses stratified by age (children and adults) and ethnicity (Asian and Caucasian), no significant associations between MTHFR C677T polymorphism and ALL risk were observed. Conclusions The current study found no sufficient evidence of a protective role of MTHFR C677T polymorphism in ALL susceptibility. PMID:25761797

  17. PAI-1 4G-4G and MTHFR 677TT in non-hepatitis C virus/hepatitis B virus-related liver cirrhosis

    PubMed Central

    Pasta, Linda; Pasta, Francesca

    2015-01-01

    AIM: To evaluate the different roles of thrombophilia in patients with and without viral etiology. The thrombophilic genetic factors (THRGFs), PAI-1 4G-4G, MTHFR 677TT, V Leiden 506Q and prothrombin 20210A, were studied as risk factors in 1079 patients with liver cirrhosis (LC), enrolled from January 2000 to January 2014. METHODS: All Caucasian LC patients consecutively observed in a fourteen-year period were included; the presence of portal vein thrombosis (PVT) and Budd Chiari syndrome (BCS) was registered. The differences between the proportions of each THRGF with regard to the presence or absence of viral etiology and the frequencies of the THRGF genotypes with those predicted in a population by the Hardy-Weinberg equilibrium were registered. RESULTS: Four hundred and seventeen/one thousand and seventy-six patients (38.6%) showed thrombophilia: 217 PAI-1 4G-4G, 176 MTHFR C677TT, 71 V Leiden factor and 41 prothrombin G20210 A, 84 with more than 1 THRGF; 350 presented with no viral liver cirrhosis (NVLC) and 729 with, called viral liver cirrhosis (VLC), of whom 56 patients were hepatitis C virus + hepatitis B virus. PAI-1 4G-4G, MTHFR C677TT, the presence of at least one TRHGF and the presence of > 1 THRGF, were statistically more frequent in patients with NVLC vs patients with VLC: All χ2 > 3.85 and P < 0.05. Patients with PVT and/or BCS with at least one TRHGF were 189/352 (53.7%). The Hardy-Weinberg of PAI-1 and MTHFR 677 genotypes deviated from that expected from a population in equilibrium in patients with NVLC (respectively χ2 = 39.3; P < 0.000 and χ2 = 27.94; P < 0.05), whereas the equilibrium was respected in VLC. CONCLUSION: MTHFR 677TT was nearly twofold and PAI-1 4G-4G more than threefold more frequently found in NVLC vs patients with VLC; the Hardy-Weinberg equilibrium of these two polymorphisms confirms this data in NVLC. We suggest that PAI-1 4G-4G and MTHFR 677TT could be considered as factors of fibrosis and thrombosis mechanisms, increasing the inflammation response, and causing the hepatic fibrosis and augmented intrahepatic vascular resistance typical of LC. PAI-1 4G-4G and MTHFR 677TT screening of LC patients could be useful, mainly in those with NVLC, to identify patients in which new drug therapies based on the attenuation of the hepatic stellate cells activation or other mechanisms could be more easily evaluated. PMID:26689658

  18. The Alu-Rich Genomic Architecture of SPAST Predisposes to Diverse and Functionally Distinct Disease-Associated CNV Alleles

    PubMed Central

    Boone, Philip M.; Yuan, Bo; Campbell, Ian M.; Scull, Jennifer C.; Withers, Marjorie A.; Baggett, Brett C.; Beck, Christine R.; Shaw, Christine J.; Stankiewicz, Pawel; Moretti, Paolo; Goodwin, Wendy E.; Hein, Nichole; Fink, John K.; Seong, Moon-Woo; Seo, Soo Hyun; Park, Sung Sup; Karbassi, Izabela D.; Batish, Sat Dev; Ordóñez-Ugalde, Andrés; Quintáns, Beatriz; Sobrido, María-Jesús; Stemmler, Susanne; Lupski, James R.

    2014-01-01

    Intragenic copy-number variants (CNVs) contribute to the allelic spectrum of both Mendelian and complex disorders. Although pathogenic deletions and duplications in SPAST (mutations in which cause autosomal-dominant spastic paraplegia 4 [SPG4]) have been described, their origins and molecular consequences remain obscure. We mapped breakpoint junctions of 54 SPAST CNVs at nucleotide resolution. Diverse combinations of exons are deleted or duplicated, highlighting the importance of particular exons for spastin function. Of the 54 CNVs, 38 (70%) appear to be mediated by an Alu-based mechanism, suggesting that the Alu-rich genomic architecture of SPAST renders this locus susceptible to various genome rearrangements. Analysis of breakpoint Alus further informs a model of Alu-mediated CNV formation characterized by small CNV size and potential involvement of mechanisms other than homologous recombination. Twelve deletions (22%) overlap part of SPAST and a portion of a nearby, directly oriented gene, predicting novel chimeric genes in these subjects’ genomes. cDNA from a subject with a SPAST final exon deletion contained multiple SPAST:SLC30A6 fusion transcripts, indicating that SPAST CNVs can have transcriptional effects beyond the gene itself. SLC30A6 has been implicated in Alzheimer disease, so these fusion gene data could explain a report of spastic paraplegia and dementia cosegregating in a family with deletion of the final exon of SPAST. Our findings provide evidence that the Alu genomic architecture of SPAST predisposes to diverse CNV alleles with distinct transcriptional—and possibly phenotypic—consequences. Moreover, we provide further mechanistic insights into Alu-mediated copy-number change that are extendable to other loci. PMID:25065914

  19. Meta-analyses of Blood Homocysteine Levels for Gender and Genetic Association Studies of the MTHFR C677T Polymorphism in Schizophrenia

    PubMed Central

    Nishi, Akira; Numata, Shusuke; Tajima, Atsushi; Kinoshita, Makoto; Kikuchi, Kumiko; Shimodera, Shinji; Tomotake, Masahito; Ohi, Kazutaka; Hashimoto, Ryota; Imoto, Issei; Takeda, Masatoshi; Ohmori, Tetsuro

    2014-01-01

    Previous studies suggest that elevated blood homocysteine levels and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism are risk factors for schizophrenia. However, the effects of gender and MTHFR C677T genotypes on blood homocysteine levels in schizophrenia have not been consistent. We first investigated whether plasma total homocysteine levels were higher in patients with schizophrenia than in controls with stratification by gender and by the MTHFR C677T genotypes in a large cohort (N = 1379). Second, we conducted a meta-analysis of association studies between blood homocysteine levels and schizophrenia separately by gender (N = 4714). Third, we performed a case-control association study between the MTHFR C677T polymorphism and schizophrenia (N = 4998) and conducted a meta-analysis of genetic association studies based on Japanese subjects (N = 10 378). Finally, we assessed the effect of plasma total homocysteine levels on schizophrenia by a mendelian randomization approach. The ANCOVA after adjustment for age demonstrated a significant effect of diagnosis on the plasma total homocysteine levels in all strata, and the subsequent meta-analysis for gender demonstrated elevated blood homocysteine levels in both male and female patients with schizophrenia although antipsychotic medication might influence the outcome. The meta-analysis of the Japanese genetic association studies demonstrated a significant association between the MTHFR C677T polymorphism and schizophrenia. The mendelian randomization analysis in the Japanese populations yielded an OR of 1.15 for schizophrenia per 1-SD increase in plasma total homocysteine. Our study suggests that increased plasma total homocysteine levels may be associated with an increased risk of schizophrenia. PMID:24535549

  20. Meta-analyses of blood homocysteine levels for gender and genetic association studies of the MTHFR C677T polymorphism in schizophrenia.

    PubMed

    Nishi, Akira; Numata, Shusuke; Tajima, Atsushi; Kinoshita, Makoto; Kikuchi, Kumiko; Shimodera, Shinji; Tomotake, Masahito; Ohi, Kazutaka; Hashimoto, Ryota; Imoto, Issei; Takeda, Masatoshi; Ohmori, Tetsuro

    2014-09-01

    Previous studies suggest that elevated blood homocysteine levels and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism are risk factors for schizophrenia. However, the effects of gender and MTHFR C677T genotypes on blood homocysteine levels in schizophrenia have not been consistent. We first investigated whether plasma total homocysteine levels were higher in patients with schizophrenia than in controls with stratification by gender and by the MTHFR C677T genotypes in a large cohort (N = 1379). Second, we conducted a meta-analysis of association studies between blood homocysteine levels and schizophrenia separately by gender (N = 4714). Third, we performed a case-control association study between the MTHFR C677T polymorphism and schizophrenia (N = 4998) and conducted a meta-analysis of genetic association studies based on Japanese subjects (N = 10 378). Finally, we assessed the effect of plasma total homocysteine levels on schizophrenia by a mendelian randomization approach. The ANCOVA after adjustment for age demonstrated a significant effect of diagnosis on the plasma total homocysteine levels in all strata, and the subsequent meta-analysis for gender demonstrated elevated blood homocysteine levels in both male and female patients with schizophrenia although antipsychotic medication might influence the outcome. The meta-analysis of the Japanese genetic association studies demonstrated a significant association between the MTHFR C677T polymorphism and schizophrenia. The mendelian randomization analysis in the Japanese populations yielded an OR of 1.15 for schizophrenia per 1-SD increase in plasma total homocysteine. Our study suggests that increased plasma total homocysteine levels may be associated with an increased risk of schizophrenia. PMID:24535549

  1. Molecular genetic analysis in mild hyperhomocysteinemia: A common mutation in the methylenetetrahydrofolate reductase gene is a genetic risk factor for cardiovascular disease

    SciTech Connect

    Kluijtmans, L.A.J.; Heuvel, L.P.W.J. van den; Stevens, E.M.B.

    1996-01-01

    Mild hyperhomocysteinemia is an established risk factor for cardiovascular disease. Genetic aberrations in the cystathionine P-synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) genes may account for reduced enzyme activities and elevated plasma homocysteine levels. In 15 unrelated Dutch patients with homozygous CBS deficiency, we observed the 833T{yields}C (1278T) mutation in 50% of the alleles. Very recently, we identified a common mutation (677C{yields}T; A{yields}V) in the MTHFR gene, which, in homozygous state, is responsible for the thermolabile phenotype and which is associated with decreased specific MTHFR activity and elevated homocysteine levels. We screened 60 cardiovascular patients and 111 controls for these two mutations, to determine whether these mutations are risk factors for premature cardiovascular disease. Heterozygosity for the 833T{yields}C mutation in the CBS gene was observed in one individual of the control group but was absent in patients with premature cardiovascular disease. Homozygosity for the 677C-{yields}T mutation in the MTHFR gene was found in 9 (15%) of 60 cardiovascular patients and in only 6 ({approximately}5%) of 111 control individuals (odds ratio 3.1 [95% confidence interval 1.0-9.21]). Because of both the high prevalence of the 833T-{yields}C mutation among homozygotes for CBS deficiency and its absence in 60 cardiovascular patients, we may conclude that heterozygosity for CBS deficiency does not appear to be involved in premature cardiovascular disease. However, a frequent homozygous mutation in the MTHFR gene is associated with a threefold increase in risk for premature cardiovascular disease. 35 refs., 3 figs., 1 tab.

  2. Polymorphisms in one-carbon metabolism pathway genes and risk for bladder cancer in a Tunisian population.

    PubMed

    Rouissi, Kamel; Ouerhani, Slah; Oliveira, Elisabete; Marrakchi, Raja; Cherni, Lotfi; Ben Othman, Fethi; Ben Slama, Mohamed R; Sfaxi, Mohamed; Ayed, Mohsen; Chebil, Mohamed; Amorim, António; Prata, Maria João; Benammar Elgaaied, Amel

    2009-11-01

    Cigarette smoking is the most important risk factor for bladder cancer. Moreover, epidemiologic studies have implicated several genetic variations interfering with methyl group metabolisms in susceptibility for a variety of cancers. Examples of these variations can be found in genes of the folate metabolic pathway, which is crucial in the provision of methyl groups for DNA, RNA, and protein methylation, as well as in purine and pyrimidine synthesis. We conducted a case-control study to examine the relationship between the methylenetetrahydrofolate reductase (MTHFR C677 T and MTHFR A1298C), methionine synthase (5-methyltetrahydrofolate-homocysteine methyltransferase, MTR A2756 G), methionine synthase reductase (5-methyltetrahydrofolate-homocysteine methyltransferase reductase, MTRR A66 G and MTRR C524 T), and thymidylate synthase (TYMS 2R-->3R and G/C) genotypes and the risk for bladder cancer in a Tunisian population. The isolated MTHFR 677 *T, MTRR 66 *G and MTRR 524 *T variants did not appear to influence bladder cancer susceptibility. The 3R *C/3R *C genotype for the TYMS gene appears to be a protective factor against bladder cancer development (P=0.0001; OR=0.12; 95% CI=0.03-0.40). However, patients heterozygous for MTHFR A1298C or MTR A2756 G genotypes have 1.62- and 2.13-fold higher risk, respectively, of developing bladder cancer. Moreover, the combined study of MTHFR 1298 *C and MTR 2756 *G variants with either or both MTRR 66GG and TYMS 3R *G/3R *G genotypes suggests a cumulative effect. Finally, this study evidenced that interaction between gene variations involved in folate metabolism and risk of bladder cancer increased dramatically among smokers. PMID:19837268

  3. Levofloxacin-Induced Achilles Tendinitis in a Young Adult in the Absence of Predisposing Conditions

    PubMed Central

    Durey, Areum; Baek, Yong Soo; Park, Jin Seok; Lee, Kwangsoo; Ryu, Jeong-Seon; Cheong, Moon-Hyun

    2010-01-01

    Fluoroquinolones (FQs) represent a major class of antimicrobials that have a high potential as therapeutic agents. Although FQs are generally safe for the use as antimicrobials, they may induce tendinopathic complications such as tendinitis and tendon rupture. A number of factors have been suggested to further predispose a patient to such injuries. Hitherto, a few published cases on tendon disorders have implicated levofloxacin, a more recently introduced FQ. Here, we report a patient with levofloxacin-induced Achilles tendinitis, who exhibited no known predisposing factors. A 20-year-old man without any history of disease or medication presented with community-acquired pneumonia. Levofloxacin was administered and 3 days later, he complained of pain in the left Achilles tendon and revealed redness and swelling in the area. On suspecting Achilles tendinitis, levofloxacin treatment was discontinued, and the tendinitis subsequently improved. To our knowledge, this is the first case report on FQ-induced Achilles tendinitis in Korea. PMID:20376902

  4. Etiological agents and predisposing factors of intracranial abscesses in a Greek university hospital.

    PubMed

    Sofianou, D; Selviarides, P; Sofianos, E; Tsakris, A; Foroglou, G

    1996-01-01

    The bacteriology for 21 patients with brain abscesses is presented and correlated with their predisposing conditions. Chronic otomastoiditis was the most common predisposing factor, and the overall most frequent infected sites were the frontal and temporal regions. Gram-negative non-sporeforming anaerobes of the genus Bacteroides and Fusobacterlum followed by aerobic streptococci were the predominant pathogens. Enterobacteria were only identified in postcraniotomy abscesses, while a substantial number of fastidious species was detected in suppurations related to congenital heart disease. Altogether, anaerobes alone were recovered in seven patients, aerobes alone in six, and mixed aerobes and anaerobes in four patients. These findings confirm the predominant role of anaerobes in the etiology of intracranial suppurations. PMID:8740108

  5. Trajectories of Organized Activity Participation Among Urban Adolescents: An Analysis of Predisposing Factors.

    PubMed

    Eisman, Andria B; Stoddard, Sarah A; Bauermeister, José A; Caldwell, Cleopatra H; Zimmerman, Marc A

    2016-01-01

    Organized activity participation provides important opportunities for adolescents to develop assets and resources related to positive youth development. Predisposing factors, in addition to sociodemographics and self-selection factors, may influence how youth participate over time. In this study, we used growth mixture modeling with longitudinal data from African American adolescents attending urban high schools in Flint, MI to identify subgroups of participation trajectories (Wave 1 N = 681, mean age at Wave 1 = 14.86 years, 51 % female). We measured activity participation using psychological and behavioral engagement across multiple contexts over the 4 years of high school. We examined how predisposing risk and promotive factors were related to these trajectories, accounting for sociodemographic and self-selection factors. The results indicated three participation trajectories: a low group decreasing over time (74 %), a moderate, consistent participation group (21 %) and a moderate, increasing group (5 %). More substance use was associated with lower odds of being in the moderate/consistent versus low/decreasing participation group. More parental support was associated with lower odds of being in the moderate/increasing versus the moderate/consistent group. Our results suggest that addressing predisposing factors such as substance use may help facilitate participation over time. PMID:25735866

  6. PCAP is the major known prostate cancer predisposing locus in families from south and west Europe.

    PubMed

    Cancel-Tassin, G; Latil, A; Valéri, A; Mangin, P; Fournier, G; Berthon, P; Cussenot, O

    2001-02-01

    To date four prostate cancer predisposing loci have been mapped: HPC1 (Hereditary Prostate Cancer 1) on 1q24-25, PCaP (Predisposing for Cancer Prostate) on 1q42.2-43, CAPB (Cancer Prostate and Brain) on 1p36, and HPCX on Xq27-28. We examined evidence for linkage to those loci in 64 families from south and west Europe. Genotyping of three (six for PCaP) markers encompassing the candidate regions were performed on 221 individuals including 159 affected patients. The resulting data were analysed using both parametric and non parametric linkage methods. No significant evidence of linkage to HPC1, CAPB, or HPCX was found either in the whole population or when pedigrees were stratified according to criteria specific to each locus. By contrast, results in favour of linkage to PCaP locus were observed with maximum multipoint NPL and HLOD scores of 2.8 (P = 0.0026) and 2.65 respectively. Homogeneity analysis performed with multipoint LOD scores gave an estimated proportion of families with linkage to this locus up to 50%. Particularly, families with an earlier age at diagnosis (< or = 65-years-old) contributed significantly to the evidence of linkage with a maximum multipoint NPL score of 2.03 (P = 0.024). Those results suggest that PCaP is the most frequent known locus predisposing to hereditary prostate cancer cases from families from south and west Europe. PMID:11313747

  7. New genes linked to lung cancer susceptibility in Asian women

    Cancer.gov

    An international group of scientists has identified three genes that predispose Asian women who have never smoked to lung cancer. The discovery of specific genetic variations, which have not previously been associated with lung cancer risk in other popul

  8. Germline loss-of-function mutations in LZTR1 predispose to an inherited disorder of multiple schwannomas.

    PubMed

    Piotrowski, Arkadiusz; Xie, Jing; Liu, Ying F; Poplawski, Andrzej B; Gomes, Alicia R; Madanecki, Piotr; Fu, Chuanhua; Crowley, Michael R; Crossman, David K; Armstrong, Linlea; Babovic-Vuksanovic, Dusica; Bergner, Amanda; Blakeley, Jaishri O; Blumenthal, Andrea L; Daniels, Molly S; Feit, Howard; Gardner, Kathy; Hurst, Stephanie; Kobelka, Christine; Lee, Chung; Nagy, Rebecca; Rauen, Katherine A; Slopis, John M; Suwannarat, Pim; Westman, Judith A; Zanko, Andrea; Korf, Bruce R; Messiaen, Ludwine M

    2014-02-01

    Constitutional SMARCB1 mutations at 22q11.23 have been found in ∼50% of familial and <10% of sporadic schwannomatosis cases. We sequenced highly conserved regions along 22q from eight individuals with schwannomatosis whose schwannomas involved somatic loss of one copy of 22q, encompassing SMARCB1 and NF2, with a different somatic mutation of the other NF2 allele in every schwannoma but no mutation of the remaining SMARCB1 allele in blood and tumor samples. LZTR1 germline mutations were identified in seven of the eight cases. LZTR1 sequencing in 12 further cases with the same molecular signature identified 9 additional germline mutations. Loss of heterozygosity with retention of an LZTR1 mutation was present in all 25 schwannomas studied. Mutations segregated with disease in all available affected first-degree relatives, although four asymptomatic parents also carried an LZTR1 mutation. Our findings identify LZTR1 as a gene predisposing to an autosomal dominant inherited disorder of multiple schwannomas in ∼80% of 22q-related schwannomatosis cases lacking mutation in SMARCB1. PMID:24362817

  9. Germline loss-of-function mutations in LZTR1 predispose to an inherited disorder of multiple schwannomas

    PubMed Central

    Piotrowski, Arkadiusz; Xie, Jing; Liu, Ying F; Poplawski, Andrzej B; Gomes, Alicia R; Madanecki, Piotr; Fu, Chuanhua; Crowley, Michael R; Crossman, David K; Armstrong, Linlea; Babovic-Vuksanovic, Dusica; Bergner, Amanda; Blakeley, Jaishri O; Blumenthal, Andrea L; Daniels, Molly S; Feit, Howard; Gardner, Kathy; Hurst, Stephanie; Kobelka, Christine; Lee, Chung; Nagy, Rebecca; Rauen, Katherine A; Slopis, John M; Suwannarat, Pim; Westman, Judith A; Zanko, Andrea; Korf, Bruce R; Messiaen, Ludwine M

    2015-01-01

    Constitutional SMARCB1 mutations at 22q11.23 have been found in ~50% of familial and <10% of sporadic schwannomatosis cases1. We sequenced highly conserved regions along 22q from eight individuals with schwannomatosis whose schwannomas involved somatic loss of one copy of 22q, encompassing SMARCB1 and NF2, with a different somatic mutation of the other NF2 allele in every schwannoma but no mutation of the remaining SMARCB1 allele in blood and tumor samples. LZTR1 germline mutations were identified in seven of the eight cases. LZTR1 sequencing in 12 further cases with the same molecular signature identified 9 additional germline mutations. Loss of heterozygosity with retention of an LZTR1 mutation was present in all 25 schwannomas studied. Mutations segregated with disease in all available affected first-degree relatives, although four asymptomatic parents also carried an LZTR1 mutation. Our findings identify LZTR1 as a gene predisposing to an autosomal dominant inherited disorder of multiple schwannomas in ~80% of 22q-related schwannomatosis cases lacking mutation in SMARCB1. PMID:24362817

  10. Coronary heart disease among Circassians in Israel is not associated with mutations in thrombophilia genes.

    PubMed

    Falik-Zaccai, Tzipora C; Haron, Yafa; Eilat, Danny; Harash, Bakky; Golinker, Ekaterina; Hussein, Osamah; Eisikovits, Rivka; Borochowitz, Zvi; Linn, Shai

    2003-02-01

    The Muslim Circassian community in Israel represents a unique ethnic community that has never been genetically and medically studied. One hundred and fifty-three randomly selected individuals (91 men and 62 women, ages 35 and older), both healthy or with a history of cardiovascular disease (14 men and 7 women), were studied in a cross-sectional descriptive study for mutations in three genes known to be associated with hypercoagulation. Their medical records were reviewed for risk factors and history of cardiovascular disease (CVD) and thromboembolic events. The mutation FV 1691G --> A in the gene for factor V (FV 1691G --> A), the mutation MTHFR 677C --> T in the gene 5,10-methylenetetrahydrofolate reductase, and the allele G20210A in the gene for prothrombin (PT 20210G --> A) were studied. The mutation FV 1691G --> A was observed in a heterozygous form in 1.3% of 153 studied individuals, while the PT 20210G --> A allele was identified in a heterozygous form in 6.5%. No individual was found homozygous for either of these two mutations. The MTHFR C677T mutation was present in 42.8% of the studied population in a heterozygous form and in 8.6% in a homozygous form. Serum homocysteine, folate, and B12 levels were studied among individuals heterozygous and homozygous for the MTHFR C677T mutation. There was no significant difference in the prevalence of all three mutations between individuals affected with CVD or other forms of thromboembolic disease and healthy individuals. This is the first report of a medical condition and its genetic background among Circassians. The high prevalence of CVD among Circassians was found to be etiologically unrelated to the three mutations studied in the genes for factor V, MTHFR, and prothrombin. PMID:12713146

  11. [C677T polymorphism of the methylentetrahydrofolate reductase gene in mothers of children affected with neural tube defects].

    PubMed

    Morales de Machín, Alisandra; Méndez, Karile; Solís, Ernesto; Borjas de Borjas, Lisbeth; Bracho, Ana; Hernández, María Luisa; Negrón, Aimara; Delgado, Wilmer; Sánchez, Yanira

    2015-09-01

    Neural tube defects (NTD) are the most common congenital anomalies of the central nervous system, with a multifactorial pattern of inheritance, presumably involving the interaction of several genetic and environmental factors. The methylenetetrahydrofolate reductase (MTHFR) gene 677C>T polymorphism has been implicated as a risk factor for NTD. The main objective of this research was to investigate the association of the 677C>T polymorphism of the MTHFR gene as a genetic risk factor for NTD. Molecular analysis was performed in DNA samples from 52 mothers with antecedent of NTD offspring and from 119 healthy control mothers. Using the Polymerase Chain Reaction, a 198 bases pairs fragment was digested with the restriction enzyme Hinfi. 677T MTHFR allele frequencies for the problem and the control groups were 51.92% and 34.45%, respectively, and 677C MTHFR allele frequencies were 48.08% and 65.55%, respectively. There were significant differences in allele (p: 0.002) and genotype (p: 0.007) frequencies between these two groups. The odds ratio (OR) to the TT genotype vs. the CC genotype was estimated as OR: 4.9 [95% CI: 1,347-6.416] p: 0.002; CT+TT vs. CC: OR: 2.9 [95% CI: 1.347-6.416] p: 0.005; TT vs. CT+CC: OR: 2.675 [95% CI: 1,111-6.441] p: 0.024. The data presented in this study support the relationship between MTHFR 677C>T polymorphism and risk in mothers with antecedent of NTD offspring. PMID:26710543

  12. MTHFR-1298 A>C (rs1801131) is a predictor of survival in two cohorts of stage II/III colorectal cancer patients treated with adjuvant fluoropyrimidine chemotherapy with or without oxaliplatin.

    PubMed

    Cecchin, E; Perrone, G; Nobili, S; Polesel, J; De Mattia, E; Zanusso, C; Petreni, P; Lonardi, S; Pella, N; D'Andrea, M; Errante, D; Rizzolio, F; Mazzei, T; Landini, I; Mini, E; Toffoli, G

    2015-06-01

    Adjuvant treatment based on fluoropyrimidines (FL) improves the prognosis of stage II/III colorectal cancer (CRC). Validated predictive/prognostic biomarkers would spare therapy-related morbidity in patients with a good prognosis. We compared the impact of a set of 22 FL-related polymorphisms with the prognosis of two cohorts of CRC patients treated with adjuvant FL with or without OXA, including a total of 262 cases. 5,10-Methylentetrahydrofolate reductase (MTHFR) MTHFR-1298 A>C (rs1801131) polymorphism had a concordant effect: MTHFR-rs1801131-1298CC genotype carriers had a worse disease free survival (DFS) in both the cohorts. In the pooled population MTHFR-rs1801131-1298CC carriers had also a worse overall survival. We computed a clinical score related to DFS including MTHFR-rs1801131, tumor stage, sex and tumor location, where rs1801131 is the most detrimental factor (hazard ratio=5.3, 95% confidence interval=2.2-12.9; P-value=0.0006). MTHFR-rs1801131 is a prognostic factor that could be used as an additional criteria for the choice of the proper adjuvant regimen in stage II/III colorectal cancer patients. PMID:25331073

  13. Association between the MTHFR C677T polymorphism and gastric cancer susceptibility: A meta-analysis of 5,757 cases and 8,501 controls

    PubMed Central

    CHEN, LONG; LU, NING; ZHANG, BAI-HONG; WENG, LI; LU, JUN

    2015-01-01

    Current data regarding the association between the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of developing gastric cancer are insufficient to draw definite conclusions. Therefore, the present meta-analysis was conducted to achieve a more precise estimation of the association. MEDLINE, EMBASE and Wanfang database searches resulted in the identification of 28 eligible studies describing 5,757 cases and 8,501 controls. The strength of the association between the MTHFR C677T polymorphism and gastric cancer risk were evaluated using crude odds ratios (ORs), with 95% confidence intervals (CIs). The pooled ORs were determined using homozygous (TT vs. CC), heterozygous (CT vs. CC), dominant (TT+CT vs. CC) and recessive (TT vs. CC+CT) models. When all studies were pooled into the meta-analysis, significant associations were identified between the MTHFR C677T polymorphism and the risk of gastric cancer (homozygous model: OR, 1.39; 95% CI, 1.20–1.62; heterozygous model: OR, 1.18; 95% CI, 1.05–1.32; dominant model: OR, 1.23; 95% CI, 1.10–1.38; recessive model: OR, 1.26; 95% CI, 1.12–1.42). Stratification of the data by ethnicity identified a statistically significantly elevated risk of gastric cancer in Asian MTHFR C677T polymorphism populations (homozygous model: OR, 1.64; 95% CI, 1.43–1.90; heterozygous model: OR, 1.30; 95% CI, 1.16–1.45; dominant model: OR, 1.39; 95% CI, 1.25–1.54; recessive model: OR, 1.41; 95% CI, 1.25–1.51), but not in Caucasian populations (homozygous model: OR, 1.15; 95% CI, 0.89–1.48; heterozygous model: OR, 1.03; 95% CI, 0.84–1.25; dominant model: OR, 1.05; 95% CI, 0.86–1.28; recessive model: OR, 1.09; 95% CI, 0.91–1.31). Following adjustment for heterogeneity, the current meta-analysis demonstrated that the MTHFR C677T polymorphism was not associated with the risk of gastric cancer in Caucasian individuals. Furthermore, no evidence of publication bias was observed. Thus, the current meta-analysis indicates that the MTHFR C677T allele may be a low-penetrant risk factor for the development of gastric cancer in Asian populations. PMID:26622644

  14. Maternal air pollution exposure induces fetal neuroinflammation and predisposes offspring to obesity in aduthood in a sex-specific manner

    EPA Science Inventory

    Emerging evidence suggests environmental chemical exposures during critical windows of development may contribute to the escalating prevalence of obesity. We tested the hypothesis that prenatal air pollution exposure would predispose the offspring to weight gain in adulthood. Pre...

  15. Screening of susceptibility genes and multi-gene risk analysis in gastric cancer.

    PubMed

    Shen, Xiao-bing; Wang, Jia; Li, Peng-fei; Ren, Xiao-feng; Yan, Xiao-luan; Wang, Fan

    2014-10-01

    The aim of the study was to explore the relations between the genetic polymorphism and the susceptibility to the gastric cancer in Chinese Han population, and to analyze the multi-genes risk in the development of gastric carcinoma. A case-control study of 1:1 matching was performed on 564 individuals with primary gastric carcinoma in Nanjing, China. The genotypes of CYP2E1, GSTMl, GSTTl, NAT2, ALDH2, MTHFR, XRCCl, IL-1β, VDR, and TNF were detected by molecular biological techniques (PCR-RFLP and AS-PCR). Sole gene and gene-gene interactions were analyzed using Logistic regression model. The effect of multi-genes on gastric carcinoma was analyzed using multi-gene risk analysis model, which focused on the effect of multi-gene interaction on the development of gastric carcinoma. The genotypes involved in the susceptibility of gastric carcinoma were CYP2E1(c1/c1), NAT2M1(T/T), NAT2M2(A/A), XRCC1194(T/T), NAT2 phenotype (slow acetylator), MTHFR1298(A/C), and VDR TaqI(T/T), respectively. Multi-gene risk analysis model was introduced to analyze the effect of these genes on the gastric carcinoma. The results showed that there was a strong relation between odds ratio (OR) value of polygene combination and the gene frequency. With the increase of susceptibility gene frequency, the risk distribution curve of gastric carcinoma would shift to a more dangerous phase and exhibit a quantitative relation. Our results demonstrated that the OR of each gene can be utilized as an index to assess the effect of multiple susceptible genes on the occurrence of gastric carcinoma. PMID:25245011

  16. Variants in folate pathway genes as modulators of genetic instability and lung cancer risk.

    PubMed

    Piskac-Collier, Amanda L; Monroy, Claudia; Lopez, Mirtha S; Cortes, Andrea; Etzel, Carol J; Greisinger, Anthony J; Spitz, Margaret R; El-Zein, Randa A

    2011-01-01

    Genetic instability plays a crucial role in cancer development. The genetic stability of the cell as well as DNA methylation status could be modulated by folate levels. Several studies suggested associations between polymorphisms in folate genes and alterations in protein expression and variations in serum levels of the folate. The objective of this study was to investigate the effect of folate pathway polymorphisms on modulating genetic instability and lung cancer risk. Genotyping of 5 SNPs in folate pathway genes and cytokinesis-blocked micronucleus cytome assay analysis (to determine the genetic instability at baseline and following NNK treatment) was conducted on 180 lung cancer cases and 180 age-, gender-, and smoking-matched controls. Our results showed that individually, folate pathway SNPs were not associated with cytogenetic damage or lung cancer risk. However, in a polygenic disease such as lung cancer, gene-gene interactions are expected to play an important role in determining the phenotypic variability of the diseases. We observed that interactions between MTHFR677, MTHFR1298, and SHMT polymorphisms may have a significant impact on genetic instability in lung cancer patients. With regard to cytogenetic alterations, our results showed that lymphocytes from lung cancer patients exposed to the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone [NNK] had considerably increased frequency of cytogenetic damage in presence of MTHFR 677, MTHFR 1298, and SHMT allelic variants. These findings support the notion that significant interactions may potentially modulate the lung cancer susceptibility and alter the overall the repair abilities of lung cancer patients when exposed to tobacco carcinogens such as NNK. PMID:20842733

  17. Prevalence of factor V Leiden G1691A, MTHFR C677T, and prothrombin G20210A among Asian Indian sickle cell patients.

    PubMed

    Pandey, Sanjay Kumar; Meena, Arvind; Kishor, Kamal; Mishra, R M; Pandey, Sweta; Saxena, Renu

    2012-06-01

    The prevalence of factor V (FV) Leiden G1691A, prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T mutations were investigated among 90 sickle trait, 61 sickle homozygous, 75 sickle beta thalassemia, and 15 HbSD Asian Indian sickle cell patients. In all, 297 healthy controls were evaluated to compare the polymorphism frequency. The prevalence of FV Leiden heterozygous G>A were significant in the group (P = .02), while PRT G20210A polymorphism was not seen among patients as well as controls. However, an increased frequency of the MTHFR 677 C>T genotype was seen among patients as well as controls, but this was not statistically significant (P = .13). This suggested a low impact of inherited hypercoagulability risk factors in the pathogenesis of sickle cell disease and/or its complications. PMID:22084413

  18. Factor V-Leiden, prothrombin G20210A, and MTHFR C677T mutations among patients with sickle cell disease in Eastern Saudi Arabia.

    PubMed

    Fawaz, Naglaa A; Bashawery, Layla; Al-Sheikh, Iman; Qatari, Ahlam; Al-Othman, Sara S; Almawi, Wassim Y

    2004-07-01

    The prevalence of factor V Leiden, prothrombin G20210A, and MTHFR C677T mutations were investigated among 87 Saudi sickle cell disease (SCD) patients (38 males and 49 females) and 105 healthy controls (65 males and 40 females). The prevalences of factor V Leiden (P = 0.174) and PRT G20210A (P = 0.397) were not different between patients and controls, thereby giving no support to an association of either single-point mutation with SCD. However, an increased prevalence of the MTHFR 677 T/T genotype was seen among patients (8/87) compared to controls (4/105), but this was not statistically significant (P = 0.217; OR = 2.56). This suggested a low impact of inherited hypercoagulability risk factors in the pathogenesis of SCD and/or its complications. PMID:15224376

  19. Cerebral venous sinus thrombosis presenting as transient ischemic attacks in a case with homozygous mutations of MTHFR A1298C and CG677T.

    PubMed

    Yildiz, Ozlem Kayim; Cevik, Seyda; Cil, Gulsum; Oztoprak, Ibrahim; Bolayir, Ertugrul; Topaktas, Suat

    2012-01-01

    We report a case with recurrent, transient attacks of slurred speech, weakness, and numbness of the right half of the face and the right arm without seizure activity, accompanied by headache and double vision. Neurologic examination revealed bilateral papilledema and right abducens palsy. Brain magnetic resonance imaging revealed thrombosis of the dural venous sinuses and the cortical veins, with no evidence of parenchymal lesion. Homozygous mutations were found for methylenetetrahydrofolate reductase (MTHFR) A1298C and MTHFR CG677T. Anticoagulation with heparin and warfarin resulted in prompt cessation of the transient attacks, as well as the signs and symptoms of increased intracranial pressure. This report documents that, although rare, transient ischemic attacks can result from cerebral venous thrombosis. PMID:20833086

  20. Methylenetetrahydrofolate reductase (MTHFR) genetic variation and major depressive disorder prognosis: A five-year prospective cohort study of primary care attendees.

    PubMed

    Bousman, Chad A; Potiriadis, Maria; Everall, Ian P; Gunn, Jane M

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) genetic variation has been associated with the diagnosis of major depressive disorder (MDD) but no study to date has examined the effect MTHFR variation has on MDD prognosis. We sought to examine the prospective effects of two common MTHFR variants (C677T and A1298C) as well as seven haplotype-tagging single nucleotide polymorphisms (htSNPs) on MDD prognosis over a 5-year (60-month) period. Participants were 147 depressed primary care attendees enrolled in the Diagnosis, Management and Outcomes of Depression in Primary Care (diamond) prospective cohort study. Prognosis of MDD was measured using three methods: (1) DSM-IV criteria, (2) Primary Care Evaluation of Mental Disorders Patient Health Questionnaire-9 (PHQ-9), and (3) Center for Epidemiologic Studies Depression Scale (CESD). DSM-IV criteria for MDD was assessed using the Composite International Diagnostic Interview at baseline and 24, 36, 48, and 60 months post-baseline; whereas, PHQ-9 and CESD measures were employed at baseline and 12, 24, 36, 48, and 60 months post-baseline. Repeated measures analysis of variance showed that PHQ-9 symptom severity trajectories differed by C677T genotype (F?=?3.34, df?=?2,144, P?=?0.038), with 677CC genotype showing the most severe symptom severity course over the 60 months of observation. Neither the A1298C polymorphism nor any of the htSNPs were associated with MDD prognosis regardless of measure used. Our results suggest that the MTHFR C677T polymorphism may serve as a marker for MDD prognosis pending independent replication. PMID:24123968

  1. MTHFR 677T Is a Strong Determinant of the Degree of Hearing Loss Among Polish Males with Postlingual Sensorineural Hearing Impairment

    PubMed Central

    Pollak, Agnieszka; Mueller-Malesinska, Malgorzata; Lechowicz, Urszula; Skorka, Agata; Korniszewski, Lech; Sobczyk-Kopciol, Agnieszka; Waskiewicz, Anna; Broda, Grazyna; Iwanicka-Pronicka, Katarzyna; Oldak, Monika; Skarzynski, Henryk

    2012-01-01

    Hearing impairment (HI) is the most common sensory handicap. Congenital HI often has a genetic basis, whereas the etiology of nonsyndromic postlingual HI (npHI) usually remains unidentified. Our purpose was to test whether the MTHFR C677T (rs1801133) polymorphism affecting folate metabolism is associated with the occurrence or severity of npHI. We studied rs1801133 genotypes in 647 npHI patients (age <40, sudden sensorineural loss excluded, HI characterized as mean of better ear hearing thresholds for 0.5–8 kHz) and 3273 adult controls from the background population. Genotype distribution among patients and controls was similar, but among male cases (n=302) we found a dose-dependent correlation of MTHFR 677T with the degree of HI (mean thresholds in dB: 38.8, 44.9, and 53.3, for CC, CT, and TT genotypes, respectively; p=0.0013, pcor.=0.017). Among male patients rs1801133 TT significantly increased the risk of severe/profound HI (odds ratio=4.88, p=0.001). Among controls the known effect of MTHFR 677T on plasma total homocysteine was more pronounced in men than in women (p<0.00004 for genotype-sex interaction) suggesting that in Poland folate deficiency is more prevalent in males. In conclusion, we report a novel strong effect of MTHFR 677T among males with npHI. The functional significance of rs1801133 suggests that these patients may benefit from folate supplementation—an intervention which is simple, cheap, and devoid of side effects. PMID:22424391

  2. Identifying multiple causative genes at a single GWAS locus.

    PubMed

    Flister, Michael J; Tsaih, Shirng-Wern; O'Meara, Caitlin C; Endres, Bradley; Hoffman, Matthew J; Geurts, Aron M; Dwinell, Melinda R; Lazar, Jozef; Jacob, Howard J; Moreno, Carol

    2013-12-01

    Genome-wide association studies (GWAS) are useful for nominating candidate genes, but typically are unable to establish disease causality or differentiate between the effects of variants in linkage disequilibrium (LD). Additionally, some GWAS loci might contain multiple causative variants or genes that contribute to the overall disease susceptibility at a single locus. However, the majority of current GWAS lack the statistical power to test whether multiple causative genes underlie the same locus, prompting us to adopt an alternative approach to testing multiple GWAS genes empirically. We used gene targeting in a disease-susceptible rat model of genetic hypertension to test all six genes at the Agtrap-Plod1 locus (Agtrap, Mthfr, Clcn6, Nppa, Nppb, and Plod1) for blood pressure (BP) and renal phenotypes. This revealed that the majority of genes at this locus (five out of six) can impact hypertension by modifying BP and renal phenotypes. Mutations of Nppa, Plod1, and Mthfr increased disease susceptibility, whereas Agtrap and Clcn6 mutations decreased hypertension risk. Reanalysis of the human AGTRAP-PLOD1 locus also implied that disease-associated haplotype blocks with polygenic effects were not only possible, but rather were highly plausible. Combined, these data demonstrate for the first time that multiple modifiers of hypertension can cosegregate at a single GWAS locus. PMID:24006081

  3. Methylation analysis of multiple genes in blood DNA of Alzheimer's disease and healthy individuals.

    PubMed

    Tannorella, Pierpaola; Stoccoro, Andrea; Tognoni, Gloria; Petrozzi, Lucia; Salluzzo, Maria Grazia; Ragalmuto, Alda; Siciliano, Gabriele; Haslberger, Alexander; Bosco, Paolo; Bonuccelli, Ubaldo; Migliore, Lucia; Coppedè, Fabio

    2015-07-23

    We collected blood DNA from 120 late-onset Alzheimer's disease (AD) patients and 115 healthy matched controls and analysed the methylation levels of genes involved in amyloid-beta peptide production (PSEN1 and BACE1), in DNA methylation (DNMT1, DNMT3A and DNMT3B), and in one-carbon metabolism (MTHFR), searching for correlation with age and gender, with biomarkers of one-carbon metabolism (plasma homocysteine, and serum folate and vitamin B12 levels), and with disease status (being healthy or having AD). We also evaluated the contribution of the APOE ?4 allele, the major late-onset AD genetic risk factor, to the studied gene methylation levels. All the genes showed low mean methylation levels (<5%) in both AD and control DNA, no difference between groups, and no correlation with the studied biomarkers, except for MTHFR that showed methylation levels ranging from 5% to 75%, and correlation with circulating biomarkers of one-carbon metabolism. However, mean MTHFR methylation levels were similar between groups (31.1% in AD and 30.7% in controls, P=0.58). Overall, present data suggest that none of the studied regions is differently methylated in blood DNA between AD and control subjects. PMID:26079324

  4. Gene polymorphisms in association with emerging cardiovascular risk markers in adult women

    PubMed Central

    2010-01-01

    Background Evidence on the associations of emerging cardiovascular disease risk factors/markers with genes may help identify intermediate pathways of disease susceptibility in the general population. This population-based study is aimed to determine the presence of associations between a wide array of genetic variants and emerging cardiovascular risk markers among adult US women. Methods The current analysis was performed among the National Health and Nutrition Examination Survey (NHANES) III phase 2 samples of adult women aged 17 years and older (sample size n = 3409). Fourteen candidate genes within ADRB2, ADRB3, CAT, CRP, F2, F5, FGB, ITGB3, MTHFR, NOS3, PON1, PPARG, TLR4, and TNF were examined for associations with emerging cardiovascular risk markers such as serum C-reactive protein, homocysteine, uric acid, and plasma fibrinogen. Linear regression models were performed using SAS-callable SUDAAN 9.0. The covariates included age, race/ethnicity, education, menopausal status, female hormone use, aspirin use, and lifestyle factors. Results In covariate-adjusted models, serum C-reactive protein concentrations were significantly (P value controlling for false-discovery rate ? 0.05) associated with polymorphisms in CRP (rs3093058, rs1205), MTHFR (rs1801131), and ADRB3 (rs4994). Serum homocysteine levels were significantly associated with MTHFR (rs1801133). Conclusion The significant associations between certain gene variants with concentration variations in serum C-reactive protein and homocysteine among adult women need to be confirmed in further genetic association studies. PMID:20078877

  5. MTHFR C677T and A1298C polymorphisms as predictors of radiotherapy response in head and neck squamous cell carcinoma.

    PubMed

    Anders, Q S; Stur, E; Agostini, L P; Garcia, F M; Reis, R S; Santos, J A; Mendes, S O; Maia, L L; Peterle, G T; Stange, V; Carvalho, M B; Tajara, E H; Santos, M; Silva-Conforti, A M A; Louro, I D

    2015-01-01

    The C677T and A1298C polymorphisms in methylene-tetrahydrofolate reductase (MTHFR), which regulates the release of active folate in the body, may have reduced activity. Given that folate participates in important intracellular pathways, such as nucleotide synthesis and biomolecule methylation, it seems plausible that patients with head and neck squamous cell carcinoma (HNSCC) may respond differently to radiotherapy treatments, based on genetic polymor-phisms. Therefore, this study sought to understand the role of these polymorphisms in HNSCC patient radiotherapy response. Genotypes were detected by PCR-RFLP after extraction of DNA from peripheral blood lymphocytes. Survival curves were analyzed by the Kaplan- Meier model, and significant differences were analyzed by the Wil-coxon test. Response to radiotherapy in patients with laryngeal SCC was significantly associated with the MTHFR C677T polymorphism (P = 0.030). Indeed, the presence of at least one T allele decreases the mortality rate up to 3-fold. Therefore, we propose that MTHFR C677T may represent a putative biomarker for radiotherapy prognosis in la-ryngeal SCC patients. PMID:26535623

  6. Associations between single nucleotide polymorphisms in folate uptake and metabolizing genes with blood folate, homocysteine, and DNA uracil concentrations1234

    PubMed Central

    DeVos, Lauren; Chanson, Aurelie; Liu, Zhenhua; Ciappio, Eric D; Parnell, Laurence D; Mason, Joel B; Tucker, Katherine L; Crott, Jimmy W

    2009-01-01

    Background Folate is an essential nutrient that supports nucleotide synthesis and biological methylation reactions. Diminished folate status results in chromosome breakage and is associated with several diseases, including colorectal cancer. Folate status is also inversely related to plasma homocysteine concentrations—a risk factor for cardiovascular disease. Objective We sought to gain further understanding of the genetic determinants of plasma folate and homocysteine concentrations. Because folate is required for the synthesis of thymidine from uracil, the latter accumulating and being misincorporated into DNA during folate depletion, the DNA uracil content was also measured. Design Thirteen single nucleotide polymorphisms (SNPs) in genes involved in folate uptake and metabolism, including folate hydrolase (FOLH1), folate polyglutamate synthase (FPGS), ?-glutamyl hydrolase (GGH), methylene tetrahydrofolate reductase (MTHFR), methionine synthase (MTR), proton-coupled folate transporter (PCFT), and reduced folate carrier (RFC1), were studied in a cohort of 991 individuals. Results The MTHFR 677TT genotype was associated with increased plasma homocysteine and decreased plasma folate. MTHFR 1298A>C and RFC1 intron 5A>G polymorphisms were associated with significantly altered plasma homocysteine concentrations. The FOLH1 1561C>T SNP was associated with altered plasma folate concentrations. The MTHFR 677TT genotype was associated with a ?34% lower DNA uracil content (P = 0.045), whereas the G allele of the GGH – 124T>G SNP was associated with a stepwise increase in DNA uracil content (P = 0.022). Conclusion Because the accumulation of uracil in DNA induces chromosome breaks, mutagenic lesions, we suggest that, as for MTHFR C677T, the GGH – 124 T>G SNP may modulate the risk of carcinogenesis and therefore warrants further attention. PMID:18842806

  7. Primary Otomycosis in the Indian Subcontinent: Predisposing Factors, Microbiology, and Classification

    PubMed Central

    Kotigadde, Subbannayya; Shekhar, Manisha; Thada, Nikhil Dinaker; Prabhu, Prashanth; D' Souza, Tina; Prasad, Kishore Chandra

    2014-01-01

    Objective. To define otomycosis and determine the predisposing factors and microbiology in primary otomycosis. Study Design. Prospective study of two years and review of the literature. Setting. Academic Department of Otolaryngology in a coastal city in India. Patients. 150 immunocompetent individuals of whom 100 consecutive patients with a clinical diagnosis of otomycosis are considered as the study group and 50 consecutive patients with no otomycosis are considered as the control group. Results and Observations. Instillation of coconut oil (42%), use of topical antibiotic eardrops (20%), and compulsive cleaning of external ear with hard objects (32%) appeared to be the main predisposing factors in otomycosis. Aspergilli were the most common isolates (80%) followed by Penicillium (8%), Candida albicans (4%), Rhizopus (1%), and Chrysosporium (1%), the last being reported for the first time in otomycosis. Among aspergilli, A. niger complex (38%) was the most common followed by A. fumigatus complex (27%) and A. flavus complex (15%). Bacterial isolates associated with fungi in otomycosis were S. aureus, P. aeruginosa, and Proteus spp. In 42% of healthy external ears fungi were isolated. Conclusion. Aspergillus spp. were the most common fungi isolated, followed by Penicillium. Otomycotic ears are often associated with bacterial isolates when compared to normal ears. Fungi are also present in a significant number of healthy external auditory canals and their profiles match those in cases of otomycosis. The use of terms “primary” and “secondary” otomycosis is important to standardize reporting. PMID:24949016

  8. Univariate and multivariate analyses of risk factors predisposing to auditory toxicity in patients receiving aminoglycosides.

    PubMed Central

    Gatell, J M; Ferran, F; Araujo, V; Bonet, M; Soriano, E; Traserra, J; SanMiguel, J G

    1987-01-01

    Risk factors predisposing to auditory toxicity of aminoglycosides were analyzed from records of 187 patients enrolled in three prospective randomized trials comparing the toxicity of netilmicin, tobramycin, and amikacin. Patients were eligible if they received three or more days of therapy and at least two serial audiograms were available. The overall auditory toxicity rate was 9.6% (18 of 187). Auditory toxicity was detected in 4.4, 10.8, and 23.5% of patients given netilmicin, tobramycin, and amikacin, respectively (P = 0.05). In the univariate analysis, patients who developed auditory toxicity were significantly older (P = 0.01) and had a significantly higher (P = 0.04) percentage of trough levels of netilmicin or tobramycin above 2 mg/liter or amikacin above 5 mg/liter. In the final logistic regression model, only age was retained as independently influencing the development of auditory toxicity (P less than 0.00001). Conversely, factors that did not add significantly to the prediction of auditory toxicity were aminoglycoside serum levels, total aminoglycoside dose, duration of therapy, sex, peak temperature, presence of bacteremia, shock, liver cirrhosis, dehydration, previous otic pathology or renal failure, and development of renal toxicity. At least in certain populations, age is the most important predisposing factor for the development of auditory toxicity in patients receiving aminoglycosides. PMID:3674849

  9. A new predisposing factor for trigemino-cardiac reflex during subdural empyema drainage: a case report

    PubMed Central

    2010-01-01

    Introduction The trigemino-cardiac reflex is defined as the sudden onset of parasympathetic dysrhythmia, sympathetic hypotension, apnea, or gastric hypermotility during stimulation of any of the sensory branches of the trigeminal nerve. Clinically, trigemino-cardiac reflex has been reported to occur during neurosurgical skull-base surgery. Apart from the few clinical reports, the physiological function of this brainstem reflex has not yet been fully explored. Little is known regarding any predisposing factors related to the intraoperative occurrence of this reflex. Case presentation We report the case of a 70-year-old Caucasian man who demonstrated a clearly expressed form of trigemino-cardiac reflex with severe bradycardia requiring intervention that was recorded during surgical removal of a large subdural empyema. Conclusion To the best of our knowledge, this is the first report of an intracranial infection leading to perioperative trigemino-cardiac reflex. We therefore add a new predisposing factor for trigemino-cardiac reflex to the existing literature. Possible mechanisms are discussed in the light of the relevant literature. PMID:21118536

  10. [Factors predisposing to acute urine retention in patients with prostatic adenoma].

    PubMed

    Davidov, M I

    2007-01-01

    The aim of the trial was to study factors predisposing to acute urine retention (AUR) in patients with prostatic adenoma (PA). The trial was made in Perm Center for Urgent Urological Care. This allowed registration and analysis of all cases of AUR in the city with population of 1 million people. For 11 years there were 1504 episodes of AUR in 1130 PA patients. One AUR episode was registered in 888 (78.6%) patients, two to four--in 242. Questioning of the patients, the disease histories analysis provided information on the factors predisposing to AUR. The following factors provoked AUR: alcohol intake (25.9%), water loading (11.5%), medication (atropin, belladonna, efedrin, aminasin, tizercin, phenobarbital, imisin, promedol, lazix, etc.; 11.4%), acute inflammation of the adenomatous nodes (7.4%), cold (6.7%), spicy food (5.5%), flebitis of the hemorrhoidal veins (5.5%), fatigue (5.1%), emotional stress (3.9%), forced urine retention (3.1%), bed rest (2.8%), sexual excesses (2%), surgical interventions (2%), etc. AUR occurred more often in the morning (at 4 to 8 o'clock a.m.), in the holidays and after them (92.5% of these patients took alcohol), on days with acute fluctuations of atmospheric pressure, temperature, air humidity. A complex of meteoprophylaxis of AUR is proposed. PMID:17580384

  11. Predisposing and precipitating factors for falls among older people in residential care.

    PubMed

    Kallin, K; Lundin-Olsson, L; Jensen, J; Nyberg, L; Gustafson, Y

    2002-09-01

    Falls and their consequences are serious health problems among older populations. To study predisposing and precipitating factors for falls among older people in residential care we used a cross-sectional study design with a prospective follow up for falls. Fifty-eight women and 25 men, with a mean age of 79.6 y, were included and prospectively followed up regarding falls for a period of 1 y after baseline assessments. All those who fell were assessed regarding factors that might have precipitated the fall. The incidence rate was 2.29 falls/person years. Antidepressants (selective serotonin reuptake inhibitors, SSRIs), impaired vision and being unable to use stairs without assistance were independently associated with being a 'faller'. Twenty-eight (53.8%) of the fallers suffered injuries as a result of their falls, including 21 fractures. Twenty-seven percent of the falls were judged to be precipitated by an acute illness or disease and 8.6% by a side effect of a drug. Acute symptoms of diseases or drug side effects were associated with 58% of the falls which resulted in fractures. We conclude that SSRIs seem to constitute one important factor that predisposes older people to fall, once or repeatedly. Since acute illnesses and drug side-effects were important precipitating factors, falls should be regarded as a possible symptom of disease or a side-effect of a drug until it is proven otherwise. PMID:12209401

  12. Assessing factors that may predispose Minnesota farms to wolf predation on cattle

    USGS Publications Warehouse

    Mech, L.D.; Harper, E.K.; Meier, T.J.; Paul, W.J.

    2000-01-01

    Wolf (Canis lupus) depredations on livestock cause considerable conflict and expense in Minnesota. Furthermore, claims are made that such depredations are fostered by the type of animal husbandry practiced. Thus, we tried to detect factors that might predispose farms in Minnesota to wolf depredations. We compared results of interviews with 41 cattle farmers experiencing chronic cattle losses to wolves (chronic farms) with results from 41 nearby matched farms with no wolf losses to determine farm characteristics or husbandry practices that differed and that therefore might have affected wolf depredations. We also used a Geographic Information System (GIS) to detect any habitat differences between the 2 types of farms. We found no differences between chronic and matched farms in the 11 farm characteristics and management practices that we surveyed, except that farms with chronic losses were larger, had more cattle, and had herds farther from human dwellings. Habitat types were the same around farms with and without losses. The role of proper carcass disposal as a possible factor predisposing farms to wolf depredations remains unclear

  13. Factors predisposing to adjacent 2 and 3:1 disjunctions: study of 161 human reciprocal translocations.

    PubMed Central

    Jalbert, P; Sele, B

    1979-01-01

    Reciprocal translocations produce imbalances by three types of disjunction which are, in decreasing frequency, adjacent 1, 3:1, and adjacent 2. Adjacent 1 disjunction produces duplication deficiencies of inverse topography to those of adjacent 2. The imbalanced chromosome segments in one of these types are balanced in the other. The disjunction 3:1 produces pure trisomies and monosomies. The following situations predispose to adjacent 2 disjunction: translocations between the long arms of two acrocentric chromosomes or between one of these and that of a No 9 chromosome; centric segments, either short or carrying a heterochromatic zone (9qh); a balanced translocation in the mother. The factors predisposing to the disjunction adjacent 2 operate by selection, or directly on the meiotic configuration. Some of them (shortness of the interstitial segment, shortness of the short arms of translocation chromosomes) act in both these ways. Their influence is probably responsible for the repetitive and exclusive character of this disjunction. The conditions for the occurrence of the 3:1 disjunctions seem less strict than those for adjacent 2, although they should be of the same nature (involvement of acrocentrics or a chromosome 9 in the translocation, maternal origin). Images PMID:395305

  14. Post spinal puncture headache, an old problem and new concepts: review of articles about predisposing factors

    PubMed Central

    Jabbari, Ali; Alijanpour, Ebrahim; Mir, Mehrafza; Bani hashem, Nadia; Rabiea, Seyed Mozaffar; Rupani, Mohammad Ali

    2013-01-01

    Post spinal puncture headache (PSPH) is a well known complication of spinal anesthesia. It occurs after spinal anesthesia induction due to dural and arachnoid puncture and has a significant effect on the patient’s postoperative well being. This manuscript is based on an observational study that runs on Babol University of Medical Sciences and review of literatures about current concepts about the incidence, risk factors and predisposing factors of post spinal puncture headache. The overall incidence of post-dural puncture headache after intentional dural puncture varies form 0.1-36%, while it is about 3.1% by atraumatic spinal needle 25G Whitacre. 25G Quincke needle with a medium bevel cutting is popular with widespread use and the incidence of PSPH is about 25%, but its incidence obtained 17.3% by spinal needle 25G Quincke in our observation. The association of predisposing factors like female, young age, pregnancy, low body mass index, multiple dural puncture, inexpert operators and past medical history of chronic headache, expose the patient to PSPH. The identification of factors that predict the likelihood of PSPH is important so that measures can be taken to minimize this painful complication resulting from spinal anesthesia. PMID:24009943

  15. The MET13 Methylenetetrahydrofolate Reductase Gene Is Essential for Infection-Related Morphogenesis in the Rice Blast Fungus Magnaporthe oryzae

    PubMed Central

    Wang, Hong; Wang, Congcong; Li, Ya; Yue, Xiaofeng; Ma, Zhonghua; Talbot, Nicholas J.; Wang, Zhengyi

    2013-01-01

    Methylenetetrahydrofolate reductases (MTHFRs) play a key role in the biosynthesis of methionine in both prokaryotic and eukaryotic organisms. In this study, we report the identification of a novel T-DNA-tagged mutant WH672 in the rice blast fungus Magnaporthe oryzae, which was defective in vegetative growth, conidiation and pathogenicity. Analysis of the mutation confirmed a single T-DNA insertion upstream of MET13, which encodes a 626-amino-acid protein encoding a MTHFR. Targeted gene deletion of MET13 resulted in mutants that were non-pathogenic and significantly impaired in aerial growth and melanin pigmentation. All phenotypes associated with Δmet13 mutants could be overcome by addition of exogenous methionine. The M. oryzae genome contains a second predicted MTHFR-encoding gene, MET12. The deduced amino acid sequences of Met13 and Met12 share 32% identity. Interestingly, Δmet12 mutants produced significantly less conidia compared with the isogenic wild-type strain and grew very poorly in the absence of methionine, but were fully pathogenic. Deletion of both genes resulted in Δmet13Δmet12 mutants that showed similar phenotypes to single Δmet13 mutants. Taken together, we conclude that the MTHFR gene, MET13, is essential for infection-related morphogenesis by the rice blast fungus M. oryzae. PMID:24116181

  16. Cardiovascular Events Are Not Associated with MTHFR Polymorphisms, But Are Associated with Methotrexate Use and Traditional Risk Factors in US Veterans with Rheumatoid Arthritis

    PubMed Central

    Davis, Lisa A.; Cannon, Grant W.; Pointer, Lauren F.; Haverhals, Leah M.; Wolff, Roger K.; Mikuls, Ted R.; Reimold, Andreas M.; Kerr, Gail S.; Richards, J. Steuart; Johnson, Dannette S.; Valuck, Robert; Prochazka, Allan; Caplan, Liron

    2014-01-01

    Objective C677T and A1298C polymorphisms in the enzyme methylenetetrahydrofolate reductase (MTHFR) have been associated with increased cardiovascular (CV) events in non-rheumatoid arthritis (RA) populations. We investigated potential associations of MTHFR polymorphisms and use of methotrexate (MTX) with time-to-CV event in data from the Veterans Affairs Rheumatoid Arthritis (VARA) registry. Methods VARA participants were genotyped for MTHFR polymorphisms. Variables included demographic information, baseline comorbidities, RA duration, autoantibody status, and disease activity. Patients’ comorbidities and outcome variables were defined using International Classification of Diseases-9 and Current Procedural Terminology codes. The combined CV event outcome included myocardial infarction (MI), percutaneous coronary intervention, coronary artery bypass graft surgery, and stroke. Cox proportional hazards regression was used to model the time-to-CV event. Results Data were available for 1047 subjects. Post-enrollment CV events occurred in 97 patients (9.26%). Although there was a trend toward reduced risk of CV events, MTHFR polymorphisms were not significantly associated with time-to-CV event. Time-to-CV event was associated with prior stroke (HR 2.01, 95% CI 1.03–3.90), prior MI (HR 1.70, 95% CI 1.06–2.71), hyperlipidemia (HR 1.57, 95% CI 1.01–2.43), and increased modified Charlson-Deyo index (HR 1.23, 95% CI 1.13–1.34). MTX use (HR 0.66, 95% CI 0.44–0.99) and increasing education (HR 0.87, 95% CI 0.80–0.95) were associated with a lower risk for CV events. Conclusion Although MTHFR polymorphisms were previously associated with CV events in non-RA populations, we found only a trend toward decreased association with CV events in RA. Traditional risk factors conferred substantial CV risk, while MTX use and increasing years of education were protective. (First Release April 1 2013; J Rheumatol 2013;40:809–17; doi:10.3899/ jrheum.121012) PMID:23547211

  17. Genetic Association Study of Putative Functional Single Nucleotide Polymorphisms of Genes in Folate Metabolism and Spina Bifida

    PubMed Central

    Martinez, Carla A.; Northrup, Hope; Lin, Jone-Ing; Morrison, Alanna C.; Fletcher, Jack M.; Tyerman, Gayle H.; Au, Kit Sing

    2009-01-01

    OBJECTIVE We tested putative functional single nucleotide polymorphisms (SNPs) in genes which regulate the folate/homocysteine metabolism pathway for their contribution to spina bifida (SB) susceptibility. STUDY DESIGN The study consisted of 610 unrelated simplex SB patient families. Genotypes of 46 SNPs located in the coding sequence or promoter region of 11 genes were investigated. Associations between transmission of alleles and SB in the offspring were examined using the reconstruction-combined transmission disequilibrium test. RESULTS Significant association of SNP rs5742905 in cystathionine-?-synthase (CBS), rs1643649 in dihydrofolate reductase (DHFR), rs2853533 in thymidylate synthetase (TYMS), and rs3737965 in methylene-tetrahydrofolate-reductase (MTHFR) was found (p= 0.015, 0.041, 0.021, and 0.007 respectively). CONCLUSION Transmission disequilibrium of SNP alleles in CBS, DHFR, MTHFR and TYMS confers an increased susceptibility to SB. PMID:19683694

  18. In utero exposure to benzo(a)pyrene predisposes offspring to cardiovascular dysfunction in later-life

    PubMed Central

    G.E., Jules; Pratap, S.; Ramesh, A.; Hood, D.B.

    2013-01-01

    In utero exposure of the fetus to benzo(a)pyrene [B(a)P], a polycyclic aromatic hydrocarbon, is thought to dysregulate cardiovascular development. To investigate the effects of in utero B(a)P exposure on cardiovascular development, timed-pregnant Long Evans Hooded (LEH) rats were exposed to diluent or B(a)P (150, 300, 600 and 1200 ?g/kg/BW) by oral gavage on embryonic (E) days E14 (the metamorphosing embryo stage) through E17 (the 1st fetal stage). There were no significant effects of in utero exposure to B(a)P on the number of pups born per litter or in pre-weaning growth curves. Pre-weaning profiles for B(a)P metabolite generation from cardiovascular tissue were shown to be dose-dependent and elimination of these metabolites was shown to be time-dependent in exposed offspring. Systolic blood pressure on postnatal day P53 in the middle and high exposure groups of offspring were significantly elevated as compared to controls. Microarray and quantitative real-time PCR results were directly relevant to a biological process pathway in animal models for “regulation of blood pressure”. Microarray and quantitative real-time PCR analysis revealed upregulation of mRNA expression for angiotensin (AngII), angiotensinogen (AGT) and endothelial nitric oxide synthase (eNOS) in exposed offspring. Biological network analysis and gene set enrichment analysis subsequently identified potential signaling mechanisms and molecular pathways that might explain the elevated systolic blood pressures observed in B(a)P-exposed offspring. Our findings suggest that in utero exposure to B(a)P predispose offspring to functional deficits in cardiovascular development that may contribute to cardiovascular dysfunction in later life. PMID:22374506

  19. Novel NBS1 heterozygous germ line mutation causing MRE11-binding domain loss predisposes to common types of cancer.

    PubMed

    Ebi, Hiromichi; Matsuo, Keitaro; Sugito, Nobuyoshi; Suzuki, Motoshi; Osada, Hirotaka; Tajima, Kazuo; Ueda, Ryuzo; Takahashi, Takashi

    2007-12-01

    DNA damage response (DDR) pathways maintain genomic stability. A 657del5 mutation of NBS1, a key DDR component, causing the rare cancer-predisposing Nijmegen breakage syndrome has been reported nearly exclusively in Slavic populations. In this study, we describe the first identification in a Japanese population of an unprecedented type of heterozygous NBS1 mutant, termed IVS11+2insT, lacking the MRE11- and ATM-binding site at the COOH terminus. Profoundly defective in crucial binding to MRE11, MDC1, BRCA1, and wild-type NBS1, the mutant caused impaired ATM phosphorylation in response to low-dose irradiation in a heterozygous state. Importantly, whereas IVS11+2insT was found in only 2 (0.09%) of 2,348 control subjects, it was identified in 2% (2 of 96) of heterozygotes with gastric cancer, 0.8% (3 of 376) of those with colorectal cancer, and 0.4% (2 of 532) of those with lung cancer, which were comparable to frequencies reported for other DDR-related genes known to confer cancer susceptibility. The presence of the heterozygous IVS11+2insT mutation seemed to be associated with an increased risk for gastrointestinal cancers, with an odds ratio of 12.6 and 95% confidence interval (95% CI) of 2.05 to 132.1 (P = 0.0001). The odds ratios separately calculated for gastric and colorectal cancers were 25.0 (95% CI, 1.78-346.0) and 9.43 (95% CI, 1.08-113.1), respectively. These findings suggest that IVS11+2insT is associated with an increased risk for the development of certain types of common cancers, warranting future investigation including detailed phenotypic characterization of age of onset and penetrance in heterozygotes, as well as screening in other ethnic groups. PMID:18056440

  20. Prothrombotic polymorphisms, mutations, and their association with pediatric non-cardioembolic stroke in Asian-Indian patients.

    PubMed

    Biswas, Arijit; Tiwari, Arun Kumar; Ranjan, Ravi; Meena, Arvind; Akhter, Mohammad Suhail; Yadav, Birendra Kumar; Behari, Madhuri; Saxena, Renu

    2009-05-01

    Genes involved in the hemostatic mechanism are logical candidate genes for association studies in prothrombotic conditions such as stroke. Since the underlying etiology in pediatric strokes is different than adults, looking for genetic causes would be the logical thing to do in the pediatric stroke population. Fifty-eight Asian-Indian stroke patients below 15 years of age and equal number of age- and sex-matched healthy controls were the subjects for the study. The subjects were screened for 13 polymorphisms and three mutations spread across seven different candidate genes involved in the hemostatic system. Of the 13 polymorphisms and three mutations studied, four polymorphisms, HPA-I, TAFI 147Ala>Thr, methylene tetrahydrofolate reductase (MTHFR) 677 C>T, and MTHFR 1298 A>C, showed significant association with the disease phenotype. MTHFR 677 C>T showed the strongest association and therefore may have a strong predisposing role for pediatric strokes. Gene-gene interaction studies showed a strong interaction between HPA-I and MTHFR 677 C>T polymorphism. The wild type of both these polymorphisms synergistically showed a strong protective effect [p < 0.0001, O.R: 10.06(4.26-23.71)]. Polymorphisms in HPA-I and MTHFR may have important predisposing roles in the development of pediatric stroke. PMID:18836720

  1. Polymorphisms in various coagulation genes in black South African women with placental abruption.

    PubMed

    Hira, B; Pegoraro, R J; Rom, L; Govender, T; Moodley, J

    2002-05-01

    This pilot study examined Factor V Leiden (R506Q), prothrombin (20210G-->A), thrombomodulin (A455V) and MTHFR (677C-->T) in 100 Zulu-speaking black South African women with placental abruption and 217 controls. The Factor V Leiden and prothrombin variant gene alleles were not detected in either patient or control groups. The thrombomodulin polymorphic variant was not seen in the patient group but three heterozygotes (1%) were found in the controls. No homozygotes for the MTHFR T677 variant were detected in the patients but two (1%) were noted in the controls; the normal and heterozygote genotype and allele frequencies for this polymorphism were similar in the two groups. PMID:12066950

  2. Anatomic Factors that May Predispose Female Athletes to Anterior Cruciate Ligament Injury.

    PubMed

    Cheung, Edward C; Boguszewski, Daniel V; Joshi, Nirav B; Wang, Dean; McAllister, David R

    2015-01-01

    Female athletes are 2 to 10 times more likely to injure their anterior cruciate ligaments (ACL) than male athletes. There has been greater recognition of this gender discrepancy because female participation in competitive athletics has increased. Previous investigators have divided risk factors into hormonal, neuromuscular response, and anatomic subgroups. Gender variation within these groups may help explain the higher incidence of ACL injury in women. The purpose of this article is to review research examining female-specific anatomy that may predispose women to ACL injury. Specifically, we discuss how women may have increased tibial and meniscal slopes, narrower femoral notches, and smaller ACL, which may place the ACL at risk from injury. These anatomic factors, combined with other female-specific risk factors, may help physicians and researchers better understand why women appear to be more prone to ACL injury. PMID:26359837

  3. Emphysematous Cholecystitis in 24-Year-old Male Without Predisposing Factors

    PubMed Central

    Gunbey, Hediye Pinar

    2015-01-01

    Emphysematous cholecystitis (EC) is a life threatening condition characterized by gangrene of the gallbladder due to an infection with gas-forming organisms. It is more common in elderly men and has been associated with systemic disease, especially diabetes and vascular disease. Computed tomography is the most important and accurate imaging modality for the diagnosis of EC. EC should be thought of when the radiographic presence of gas is detected within the gallbladder wall or lumen. Emergency surgical intervention and antibiotic treatment for the gas-forming organism should be initiated after the diagnosis of the EC. Here, we present the imaging and pathologic findings of a 24-year-old male with EC without any predisposing factors, successfully treated with laparoscopic cholecystectomy. PMID:26393182

  4. Roles of predisposing factors and gonadal hormones in the buller syndrome of feedlot steers.

    PubMed

    Irwin, M R; Melendy, D R; Amoss, M S; Hutcheson, D P

    1979-02-15

    In a study of the role of predisposing factors and gonadal hormones in the buller syndrome, it was found that weather, amount of space available to each steer, and entry weights of the steers were not associated with increased occurrence of bulling; however, the type and timing of administration of the hormonal implant, the number of steers in a pen, and the manner in which the steers were grouped after arrival at the feedlot were found to influence the incidence of the syndrome. Serum concentrations of estradiol and testosterone in the buller steers were found to be lower during bulling than after a short period of isolation and apparent recovery from the syndrome. It was concluded that the occurrence of bulling is related to the use of hormonal implants and certain feedlot management procedures but that it is apparently not related to increased serum estrogen or testosterone concentrations. PMID:447560

  5. Osteological features in pure-bred dogs predisposing to cervical spinal cord compression

    PubMed Central

    BREIT, S.; KÜNZEL, W.

    2001-01-01

    Relative to body size, midsagittal and interpedicular diameters of the cranial and caudal aspects of cervical vertebral foramina (C3–C7) were found to be significantly (P < 0·05) larger in small breeds than in large breeds and Dachshunds, and also larger in Dachshunds (P < 0·05) than in large breeds. This condition increases the risk for spinal cord compression resulting from relative stenosis of the cervical vertebral foramina, especially in large dogs, and this is also exacerbated by the typical shape of the vertebral foramina (i.e. dorsoventrally flattened cranially and bilaterally narrowed caudally). Within large dogs those breeds highly predisposed to cervical spinal cord compression were Great Danes (the breed with the smallest midsagittal vertebral foramen diameters from cranial C6 to cranial T1) and Doberman Pinschers, because of the most strikingly cranially dorsoventrally narrowed cone-shaped vertebral foramina at C6 and C7. The existence of a small midsagittal diameter in the cranial cervical spine was a high risk factor predisposing to spinal cord compression in small breeds and Dachshunds. Remarkable consistency was noted between the spinal level of the maximum enlargement of the spinal cord which previously was reported to be at C6, and the site of maximum enlargement of the vertebral canal currently stated in Dachshunds and small breeds. In large breeds the maximum enlargement of the vertebral canal tended to be located more caudally at the caudal limit of C7. The average age at which large dogs were most susceptible to noxious factors causing abnormal growth of the pedicles was determined to be 16 wk. PMID:11760884

  6. Weathering grade of rock masses as a predisposing factor to slope instabilities: Reconnaissance and control procedures

    NASA Astrophysics Data System (ADS)

    Borrelli, L.; Greco, R.; Gullà, G.

    2007-06-01

    Weathering of rock masses often assumes importance as a predisposing factor to slope instability and it is possible to map it at various scales depending on the different purposes. The effects of weathering processes are particularly intense on crystalline rocks (plutonic and metamorphic). These rocks are present in large areas of the globe and widespread in Calabria. The relationships between rock mass weathering grades and slope instabilities are analysed, with reference to sectors (1:50,000 scale) and areas (1:10,000 scale) where crystalline rocks are strongly affected by weathering. To this aim a reconnaissance procedure has been proposed to delimitate the zones with different weathering condition, three macro-classes at average scale (1:50,000) and six classes at detail scale (1:10,000). In this procedure first analysis of aerial photos and then field observations of representative situations have been used. The reconnaissance procedure has been verified in a selected study area (Acri), whose geological features are provided, by the comparison with weathering maps obtained by means of a control procedure. This last procedure consists of observations and index tests carried out in check points located in representative check sites (discolouration, sound when struck by geological hammer, effect of the point of geological pick, breaking with the hands, rebound of Schmidt Hammer, grain-size analysis). The results obtained confirm through quantitative data that the weathering of a rock mass can be assumed as a predisposing factor to slope instability. At average scale (1:50,000) the reconnaissance procedure is able to give weathering maps representative for this type of evaluation (the ratio between the landslides area in each weathering macro-class and the whole landslide area goes from 67% to 14% for the macro-class A and from 24% to 9% for the macro-class B); at detail scale (1:10,000) it is necessary to use a control procedure to obtain weathering maps indicative of predisposition to slope instabilities.

  7. Black/white differences in prenatal care utilization: an assessment of predisposing and enabling factors.

    PubMed Central

    LaVeist, T A; Keith, V M; Gutierrez, M L

    1995-01-01

    OBJECTIVE. This article reports on analysis of the predisposing and enabling factors that affect black/white differences in utilization of prenatal care services. DATA SOURCES. We use a secondary data source from a survey conducted by the Michigan Department of Public Health. STUDY DESIGN. The study uses multivariate analysis methods to examine black/white differences in (1) total number of prenatal care visits, (2) timing of start of prenatal care, and (3) adequacy of care received. We use the model advanced by Aday, Andersen, and Fleming (1980) to examine the effect of enabling and predisposing factors on black/white differences in prenatal care utilization. DATA COLLECTION. A questionnaire was administered to all women who delivered in Michigan hospitals with an obstetrical unit. PRINCIPAL FINDINGS. Enabling factors fully accounted for black/white differences in timing of start of prenatal care; however, the model could not fully account for black/white differences in the total number or the adequacy of prenatal care received. CONCLUSION. Although there are no black/white differences in the initiation of prenatal care, black women are still less likely to receive adequate care as measured by the Kessner index, or to have as many total prenatal care contacts as white women. It is possible that barriers within the health care system that could not be assessed in this study may account for the differences we observed. Future research should consider the characteristics of the health care system that may account for the unwillingness or inability of black women to continue to receive care once they initiate prenatal care. PMID:7721584

  8. High stocking density as a predisposing factor for necrotic enteritis in broiler chicks.

    PubMed

    Tsiouris, V; Georgopoulou, I; Batzios, C; Pappaioannou, N; Ducatelle, R; Fortomaris, P

    2015-01-01

    Stocking density is a management factor which has critical implications for the poultry industry. The aim of the present study was to investigate the effect of high stocking density as a predisposing factor in an experimental model of necrotic enteritis in broiler chicks. The experimental challenge model included an oral inoculation with 10-fold dose of attenuated anticoccidial vaccine and multiple oral inoculations with a specific strain of Clostridium perfringens. Two hundred and forty as hatched day-old broiler chicks were randomly allocated to four treatment groups according to the following experimental design: group N, with normal stocking density (15 birds/m(2)) and no challenge; group D, with high stocking density (30 birds/m(2)) and no challenge; group P, with normal stocking density and positive challenge; and group DP, with high stocking density and positive challenge. From each bird, the intestine, gizzard and liver were collected and scored for gross lesions. The intestinal digesta was collected for pH and viscosity determination. One caecum from each bird was taken for microbiological analysis. The statistical analysis and evaluation of the experimental data revealed significant interaction effects between "stocking density" and "challenge", regarding gross lesion scores in intestine and liver, pH values in jejunum, ileum and caeca as well as C. perfringens counts in the caeca (P ? 0.05). High stocking density in challenged birds increased the gross lesion score in the intestine (P ? 0.05), contrary to unchallenged birds. It can be concluded that high stocking density affects unfavourably the welfare and gut health of broiler chicks, predisposes to necrotic enteritis in a subclinical experimental model and increases further its importance as a management factor for the poultry industry. PMID:25563065

  9. TLR9 2848 GA Heterozygotic Status Possibly Predisposes Fetuses and Newborns to Congenital Infection with Human Cytomegalovirus

    PubMed Central

    Wujcicka, Wioletta; Paradowska, Edyta; Studzi?ska, Miros?awa; Gaj, Zuzanna; Wilczy?ski, Jan; Le?nikowski, Zbigniew; Nowakowska, Dorota

    2015-01-01

    Background Some single nucleotide polymorphisms (SNP), located in Toll-like receptor (TLR) genes, were reported to be associated with human cytomegalovirus (HCMV) infections. The study was aimed to assess the correlation of SNPs at TLR4 and TLR9 genes with the occurrence of congenital cytomegaly, based on available samples. Methods Reported case-control study included both HCMV infected and non-infected fetuses and newborns. The specimens were classified to the molecular analyses, based on serological features of the recent infection and HCMV DNAemia in body fluids. TLR SNPs were studied, using multiplex nested PCR-RFLP assay, and determined genotypes were confirmed by sequencing. Hardy-Weinberg equilibrium was assessed for the identified genotypes. The linkage disequilibrium was also estimated for TLR4 SNPs. A relationship between the status of TLR genotypes and congenital cytomegaly development was estimated, using a logistic regression model. Results Hardy Weinberg equilibrium was observed for almost all SNPs, both infected and non-infected patients, with exception of TLR4 896 A>G polymorphism in the control group (P?0.050). TLR4 896 A>G and 1196 C>T SNPs were found in linkage disequilibrium in both study groups (P?0.050). The CC genotype at TLR4 1196 SNP and the GA variant at TLR9 2848 G>A SNP were significantly associated with HCMV infection (P?0.050). The risk of congenital cytomegaly was higher in heterozygotes at TLR9 SNP than in the carriers of other genotypic variants at the reported locus (OR 4.81; P?0.050). The GC haplotype at TLR4 SNPs and GCA variants at TLR4 and TLR9 SNPs were significantly associated with HCMV infection (P?0.0001). The ACA variants were more frequent among fetuses and neonates with symptomatic, rather than asymptomatic cytomegaly (P?0.0001). Conclusions TLR4 and TLR9 polymorphisms may contribute to the development of congenital infection with HCMV in fetuses and neonates. The TLR9 2848 GA heterozygotic status possibly predisposes to HCMV infection, increasing the risk of congenital cytomegaly development. PMID:25844529

  10. Low erythrocyte folate status and polymorphic variation in folate-related genes are associated with risk of neural tube defect pregnancy.

    PubMed

    Relton, Caroline L; Wilding, Craig S; Laffling, Alison J; Jonas, Pat A; Burgess, Terry; Binks, Keith; Tawn, E Janet; Burn, John

    2004-04-01

    Previous studies have shown conflicting findings in linking polymorphic variation in folate-related genes to the risk of neural tube defect pregnancy. Recent evidence points to maternal genotype being important in determining NTD risk. A case-control study was undertaken in 97 mothers of NTD cases from the northern region of the UK. Pregnant controls (n = 190) from a regional DNA bank and non-pregnant controls (n = 100) from the same geographical area were recruited. MTHFR 677C >T, MTHFR 1298A >C, MTRR 66A >G, SHMT 1420C >T, CbetaS 844ins68, and RFC-1 80G >A allele and genotype frequencies were determined and odds ratios (OR) calculated. Erythrocyte folate levels for cases and controls were also measured and a comparison made of median erythrocyte folate levels stratified according to genotype. The MTHFR 677C >T variant was not shown to be an independent NTD risk factor in mothers of NTD-affected pregnancy. A second polymorphism in MTHFR, 1298A >C, was less frequently observed in mothers of NTD cases (OR [95% CI]=0.57 [0.33, 0.97]). Possession of compound 1298A >C and 677C >T variants elevated risk of NTD pregnancy considerably (TT/AC+TT/CC vs CC/AA OR [95% CI]=6.56 [1.10, 39.33]). Erythrocyte folate levels were persistently lower in NTD mothers (p = 0.001) despite assays being conducted many years after the index pregnancy (17.6+/-12.6 years). Erythrocyte folate levels were depressed in the presence of the MTHFR 677C >T variant. PMID:15059614

  11. C677T and A1298C polymorphisms of the methylenetetrahydrofolate reductase gene: effect on methotrexate-related toxicity in adult acute lymphoblastic leukaemia.

    PubMed

    Eissa, Deena Samir; Ahmed, Tamer Mohamed

    2013-03-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme involved in folate metabolism. Two polymorphisms, C677T and A1298C, were described leading to reduced enzyme activity. Methotrexate (MTX) is an antifolate agent of consolidation and maintenance therapy of acute lymphoblastic leukaemia (ALL). Despite its clinical success, MTX can be associated with serious toxicities resulting in treatment interruption or discontinuation, impacting disease outcome. There is evidence that MTX toxicity can be affected by polymorphisms in genes encoding for drug-metabolizing enzymes such as MTHFR. Therefore, we aimed to investigate the influence of MTHFR C677T and A1298C polymorphisms on the frequency of MTX-related toxicity, disease outcome and patients' survival. MTHFR polymorphisms were assessed in 50 adult patients with de novo ALL using real-time PCR. Patients were followed-up for the development of haematologic and/or nonhaematologic toxicity and assessment of clinical outcome. Frequency of C677T polymorphisms was 42% for TT, 24% for CT and 34% for CC; A1298C polymorphisms were 28, 6 and 66% for CC, AC and AA, respectively. MTX therapy was significantly associated with neutropaenia, hepatic and gastrointestinal toxicities, unfavourable response at day 14 of induction therapy, increased relapse and mortality rates and shorter survival in patients with 677 TT genotype than in those with CC and CT, whereas 1298 CC genotype patients had lower frequency of neutropaenia, hepatic toxicity and relapse than in those with AA and AC. Our study suggests MTHFR polymorphism as an attractive predictor of MTX-related toxicity in adult ALL, considering it a potential prognostic factor influencing disease outcome. PMID:23183238

  12. Folate intake, serum homocysteine and methylenetetrahydrofolate reductase (MTHFR) C677T genotype are not associated with oral cancer risk in Puerto Rico.

    PubMed

    Weinstein, Stephanie J; Gridley, Gloria; Harty, Lea C; Diehl, Scott R; Brown, Linda M; Winn, Deborah M; Bravo-Otero, Eleuterio; Hayes, Richard B

    2002-04-01

    We examined the relationships between folate and methionine intake, serum homocysteine levels (as a biomarker for folate metabolism), and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism genotype and risk of oral cancer in a population-based, case-control study in Puerto Rico. Structured questionnaires were used to collect information on demographic factors, usual adult diet, and tobacco and alcohol use. Oral epithelial cells and blood samples were collected from a subset of subjects. Analyses were conducted by logistic regression, adjusting for age, sex, lifetime smoking and lifetime alcohol intake, with the following numbers of cases/controls, respectively: dietary data (341/521); MTHFR genotype (148/149); and homocysteine (60/90). Although increased folate intake was associated with decreased oral cancer risk [adjusted odds ratio (OR) in highest vs. lowest quartile = 0.6, 95% confidence interval (CI): 0.4, 1.0, P(trend) = 0.05)], this finding was due almost entirely to folate intake from fruit (adjusted OR = 0.4, 95% CI: 0.2, 0.6; P(trend) = 0.0001), whereas other dietary folate sources showed no clear association. Methionine intake and serum homocysteine levels were not associated with oral cancer risk. Subjects with the MTHFR C677T homozygous variant (TT) genotype had a nonsignificantly lower risk, and risk patterns tended to differ by level of folate, methionine, alcohol intake and smoking, although the power to detect significant associations in subgroups of these variables was low. Risks for oral cancer are not folate specific; preventive recommendations for this disease should emphasize the importance of a healthy diet, including substantial intake of fruits. PMID:11925474

  13. Maternal dietary intake of folate, vitamin B12 and MTHFR 677C>T genotype: their impact on newborn's anthropometric parameters.

    PubMed

    Torres-Sánchez, Luisa; López-Carrillo, Lizbeth; Blanco-Muñoz, Julia; Chen, Jia

    2014-09-01

    In this study, we evaluated the effects of dietary intake of vitamin B12 and folate during pregnancy and their interactions with maternal polymorphism of MTHFR (677C>T; 1298A>C) on intrauterine development. Anthropometric parameters were obtained from 231 newborns that belong to a prospective birth cohort in Morelos, Mexico. Maternal dietary intake of vitamin B12 and folate was assessed using a semi-quantitative questionnaire administered during the first and third trimesters of the pregnancy. Maternal MTHFR 677C>T and 1298 A>C genotypes were determined by PCR-RFLP. The associations between deficient dietary intake of vitamin B12 (<2.0 ?g/d) and folate (<400 ?g/d) in the first and third trimesters and maternal polymorphisms of MTHFR on anthropometric parameters at birth were estimated using a multivariate linear regression model. During pregnancy, the deficient dietary intake was roughly 60 % for folate and 19 % for vitamin B12. Allelic frequencies of 677T and 1298C were 59 and 10 %, respectively. After adjusting for confounders, deficiency in maternal dietary intake of vitamin B12 (<2.0 ?g/d) was associated with a significant reduction in length (? ~ -2.4; 95 % CI -4.3; -0.6) and length-for-age at birth (? ~ -1.2; 95 % CI -2.3; -0.1) among infants whose mothers were carriers of the 677TT genotype (p for interaction = 0.02). In contrast, no association was observed between deficiency in maternal dietary intake of folate (<400 ?g/d) and any anthropometric parameter of newborns. These results suggest that supplementation with vitamin B12 during pregnancy could have a favorable impact on intrauterine fetal development mainly in populations that are genetically susceptible. PMID:25173112

  14. Morphology and Progression in Primary Varicose Vein Disorder Due to 677C>T and 1298A>C Variants of MTHFR

    PubMed Central

    Wilmanns, Christoph; Cooper, Alexis; Wockner, Leesa; Katsandris, Sotirios; Glaser, Nadine; Meyer, Alexander; Bartsch, Oliver; Binder, Harald; Walter, Paul Karl; Zechner, Ulrich

    2015-01-01

    Background Clinical assessment and prognostic stratification of primary varicose veins have remained controversial and the molecular pathogenesis is unknown. Previous data have suggested a contribution of the MTHFR (methylenetetrahydrofolate reductase) polymorphism c.677C>T. Methods We collected blood and vein specimens from 159 consecutive patients undergoing varicose vein surgery, or autologous vein reconstruction for arterial occlusive disease as controls. We compared the frequencies of c.677C>T and another polymorphism of MTHFR, c.1298A>C, with morphology and types of complicated disease. Morphology was recorded as a trunk or perforator type and peripheral congestive complication was defined as chronic venous insufficiency (CEAP C3–6) associated with edema and skin manifestations. Findings Multivariate analysis of genotypes for c.677C>T and c.1298A>C indicated that c.677C>T was associated significantly with the trunk phenotype (43/53 patients, 81%, p < 0.01), while c.1298A>C was associated significantly with the perforator phenotype (18/24 patients, 75%, p < 0.01) of primary varicose veins. Accordingly, when both c.677C>T and c.1298A>C displayed a heterozygous genotype, the patients were more likely to present with both phenotypes. Additionally, c.1298A>C was found to be strongly linked to the congestive complication (34/51 patients, 67%, p < 0.01). Interpretation Both polymorphisms of MTHFR may be involved in the morphological specification of primary varicose veins and contribute to the development of complicated disease. Funding None. PMID:26137554

  15. Association between Maternal MTHFR Polymorphisms and Nonsyndromic Cleft Lip with or without Cleft Palate in Offspring, A Meta-Analysis Based on 15 Case-Control Studies

    PubMed Central

    Pan, Xinjuan; Wang, Ping; Yin, Xinjuan; Liu, Xiaozhuan; Li, Di; Li, Xing; Wang, Yongchao; Li, Hongle; Yu, Zengli

    2015-01-01

    Background The methylenetetrahydrofolate reductase (MTHFR) is thought to be involved in the development of nonsyndromic cleft lip with or without cleft palate (NSCL/P). However, conflicting results have been obtained when evaluating the association between maternal MTHFR C677T and A1298C polymorphisms and the risk of NSCL/P. In light of this gap, a meta-analysis of all eligible case-control studies was conducted in the present study. Materials and Methods A total of 15 case-control studies were ultimately identified after a comprehensive literature search and Hardy-Weinberg equilibrium (HWE) examination. Cochrane’s Q test and index of heterogeneity (I2) indicated no obvious heterogeneity among studies. Results Fixed or random-effects models were used to calculate the pooled odds ratios (ORs). The results showed that the TT genotype in mothers increased the likelihood of having NSCL/P offspring 1.25 times (95% CI: 1.047-1.494) more than the CC homozygotes. Meanwhile, maternal TT genotype increased the risk of producing NSCL/P offspring in recessive model (OR=1.325, 95% CI: 1.124-1.562). However, the CT heterozygote and the CT+TT dominant models had no association with NSCL/P offspring compared with the CC wild-type homozygote model. Subgroup analyses based on ethnicity indicated that maternal TT genotype increased the likelihood of having NSCL/P offspring in Whites (OR=1.308, 95% CI: 1.059-1.617) and Asians (OR=1.726, 95% CI: 1.090-2.733) in recessive model. Also, subgroup analyses based on source of control showed that mothers with the 677TT genotype had a significantly increased susceptibility of having NSCL/P children in hospital based population (HB) when compared with CC homozygotes (OR=1.248, 95% CI: 1.024-1.520) and un- der the recessive model (OR=1.324, 95% CI: 1.104-1.588). Furthermore, maternal A1298C polymorphism had no significant association with producing NSCL/P offspring (dominant model OR=0.952, 95% CI: 0.816-1.111, recessive model OR=0.766, 95% CI: 0.567-1.036). Conclusion MTHFR C677T polymorphism is associated with the risk of generating NSCL/P offspring, and being a 677TT homozygote is a risk factor. MTHFR A1298C polymorphism was not associated with generating NSCL/P offspring. However, further work should be performed to confirm these findings. PMID:25780529

  16. Evidence for homosexuality gene

    SciTech Connect

    Pool, R.

    1993-07-16

    A genetic analysis of 40 pairs of homosexual brothers has uncovered a region on the X chromosome that appears to contain a gene or genes for homosexuality. When analyzing the pedigrees of homosexual males, the researcheres found evidence that the trait has a higher likelihood of being passed through maternal genes. This led them to search the X chromosome for genes predisposing to homosexuality. The researchers examined the X chromosomes of pairs of homosexual brothers for regions of DNA that most or all had in common. Of the 40 sets of brothers, 33 shared a set of five markers in the q28 region of the long arm of the X chromosome. The linkage has a LOD score of 4.0, which translates into a 99.5% certainty that there is a gene or genes in this area that predispose males to homosexuality. The chief researcher warns, however, that this one site cannot explain all instances of homosexuality, since there were some cases where the trait seemed to be passed paternally. And even among those brothers where there was no evidence that the trait was passed paternally, seven sets of brothers did not share the Xq28 markers. It seems likely that homosexuality arises from a variety of causes.

  17. 32 CFR 644.389 - Army military-modified predisposal procedures where E.O. 11954 surveys have been made.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 644.389 Army military—modified predisposal procedures where E.O. 11954 surveys have been made. (a) DEs..., appropriate commanders and DEs will be advised. The major commander will be requested to submit a Report of Excess pursuant to AR 405-90 to HQDA (DAEN-REM) Washington, DC 20314 within 15 days. DEs will...

  18. The Predisposing Factors between Dental Caries and Deviations from Normal Weight

    PubMed Central

    Chopra, Amandeep; Rao, Nanak Chand; Gupta, Nidhi; Vashisth, Shelja; Lakhanpal, Manav

    2015-01-01

    Background: Dental caries and deviations from normal weight are two conditions which share several broadly predisposing factors. So it's important to understand any relationship between dental state and body weight if either is to be managed appropriately. Aims: The study was done to find out the correlation between body mass index (BMI), diet, and dental caries among 12-15-year-old schoolgoing children in Panchkula District. Materials and Methods: A multistage sample of 12-15-year-old school children (n = 810) in Panchkula district, Haryana was considered. Child demographic details and diet history for 5 days was recorded. Data regarding dental caries status was collected using World Health Organization (1997) format. BMI was calculated and categorized according to the World Health Organization classification system for BMI. The data were subjected to statistical analysis using chi-square test and binomial regression developed using the Statistical Package for Social Sciences (SPSS) 20.0. Results: The mean Decayed Missing Filled Teeth (DMFT) score was found to be 1.72 with decayed, missing, and filled teeth to be 1.22, 0.04, and 0.44, respectively. When the sample was assessed based on type of diet, it was found that vegetarians had higher mean DMFT (1.72) as compared to children having mixed diet. Overweight children had highest DMFT (3.21) which was followed by underweight (2.31) and obese children (2.23). Binomial regression revealed that females were 1.293 times at risk of developing caries as compared to males. Fair and poor Simplified-Oral Hygiene Index (OHI-S) showed 3.920 and 4.297 times risk of developing caries as compared to good oral hygiene, respectively. Upper high socioeconomic status (SES) is at most risk of developing caries. Underweight, overweight, and obese are at 2.7, 2.5, and 3 times risk of developing caries as compared to children with normal BMI, respectively. Conclusion: Dental caries and deviations from normal weight are two conditions which share several broadly predisposing factors such as diet, SES, lifestyle and other environmental factors. PMID:25973402

  19. Predisposing, enabling, and need factors associated with high service use in a public mental health system.

    PubMed

    Lindamer, Laurie A; Liu, Lin; Sommerfeld, David H; Folsom, David P; Hawthorne, William; Garcia, Piedad; Aarons, Gregory A; Jeste, Dilip V

    2012-05-01

    The purpose of this study was twofold: (1) To investigate the individual- and system-level characteristics associated with high utilization of acute mental health services according to a widely-used theory of service use-Andersen's Behavioral Model of Health Service Use -in individuals enrolled in a large, public-funded mental health system; and (2) To document service utilization by high use consumers prior to a transformation of the service delivery system. We analyzed data from 10,128 individuals receiving care in a large public mental health system from fiscal years 2000-2004. Subjects with information in the database for the index year (fiscal year 2000-2001) and all of the following 3 years were included in this study. Using logistic regression, we identified predisposing, enabling, and need characteristics associated with being categorized as a single-year high use consumer (HU: >3 acute care episodes in a single year) or multiple-year HU (>3 acute care episodes in more than 1 year). Thirteen percent of the sample met the criteria for being a single-year HU and an additional 8% met the definition for multiple-year HU. Although some predisposing factors were significantly associated with an increased likelihood of being classified as a HU (younger age and female gender) relative to non-HUs, the characteristics with the strongest associations with the HU definition, when controlling for all other factors, were enabling and need factors. Homelessness was associated with 115% increase in the odds of ever being classified as a HU compared to those living independently or with family and others. Having insurance was associated with increased odds of being classified as a HU by about 19% relative to non-HUs. Attending four or more outpatient visits was an enabling factor that decreased the chances of being defined as a HU. Need factors, such as having a diagnosis of schizophrenia, bipolar disorder or other psychotic disorder or having a substance use disorder increased the likelihood of being categorized as a HU. Characteristics with the strongest association with heavy use of a public mental health system were enabling and need factors. Therefore, optimal use of public mental services may be achieved by developing and implementing interventions that address the issues of homelessness, insurance coverage, and substance use. This may be best achieved by the integration of mental health, intensive case management, and supportive housing, as well as other social services. PMID:21533848

  20. Genes and primary headaches: discovering new potential therapeutic targets

    PubMed Central

    2013-01-01

    Genetic studies have clearly shown that primary headaches (migraine, tension-type headache and cluster headache) are multifactorial disorders characterized by a complex interaction between different genes and environmental factors. Genetic association studies have highlighted a potential role in the etiopathogenesis of these disorders for several genes related to vascular, neuronal and neuroendocrine functions. A potential role as a therapeutic target is now emerging for some of these genes. The main purpose of this review is to describe new advances in our knowledge regarding the role of MTHFR, KCNK18, TRPV1, TRPV3 and HCRTR genes in primary headache disorders. Involvement of these genes in primary headaches, as well as their potential role in the therapy of these disorders, will be discussed. PMID:23848401

  1. Population Testing for Cancer Predisposing BRCA1/BRCA2 Mutations in the Ashkenazi-Jewish Community: A Randomized Controlled Trial

    PubMed Central

    Manchanda, Ranjit; Loggenberg, Kelly; Sanderson, Saskia; Burnell, Matthew; Wardle, Jane; Gessler, Sue; Side, Lucy; Balogun, Nyala; Desai, Rakshit; Kumar, Ajith; Dorkins, Huw; Wallis, Yvonne; Chapman, Cyril; Taylor, Rohan; Jacobs, Chris; Tomlinson, Ian; McGuire, Alistair; Beller, Uziel; Menon, Usha

    2015-01-01

    Background: Technological advances raise the possibility of systematic population-based genetic testing for cancer-predisposing mutations, but it is uncertain whether benefits outweigh disadvantages. We directly compared the psychological/quality-of-life consequences of such an approach to family history (FH)–based testing. Methods: In a randomized controlled trial of BRCA1/2 gene-mutation testing in the Ashkenazi Jewish (AJ) population, we compared testing all participants in the population screening (PS) arm with testing those fulfilling standard FH-based clinical criteria (FH arm). Following a targeted community campaign, AJ participants older than 18 years were recruited by self-referral after pretest genetic counseling. The effects of BRCA1/2 genetic testing on acceptability, psychological impact, and quality-of-life measures were assessed by random effects regression analysis. All statistical tests were two-sided. Results: One thousand, one hundred sixty-eight AJ individuals were counseled, 1042 consented, 1034 were randomly assigned (691 women, 343 men), and 1017 were eligible for analysis. Mean age was 54.3 (SD = 14.66) years. Thirteen BRCA1/2 carriers were identified in the PS arm, nine in the FH arm. Five more carriers were detected among FH-negative FH-arm participants following study completion. There were no statistically significant differences between the FH and PS arms at seven days or three months on measures of anxiety, depression, health anxiety, distress, uncertainty, and quality-of-life. Contrast tests indicated that overall anxiety (P = .0001) and uncertainty (P = .005) associated with genetic testing decreased; positive experience scores increased (P = .0001); quality-of-life and health anxiety did not change with time. Overall, 56% of carriers did not fulfill clinical criteria for genetic testing, and the BRCA1/2 prevalence was 2.45%. Conclusion: Compared with FH-based testing, population-based genetic testing in Ashkenazi Jews doesn’t adversely affect short-term psychological/quality-of-life outcomes and may detect 56% additional BRCA carriers. PMID:25435541

  2. MTHFR C677T is not a risk factor for autism spectrum disorders in South Brazil.

    PubMed

    dos Santos, Pollyanna Almeida Costa; Longo, Dânae; Brandalize, Ana Paula Carneiro; Schüler-Faccini, Lavínia

    2010-08-01

    Many studies have suggested that autism may be associated with metabolic abnormalities in the folate/homocysteine pathway, which is involved in DNA methylation, thus altering gene expression. One of the most important polymorphisms in this pathway is C677T of the methylenetetrahydrofolate reductase gene, because the T allele is associated with a decrease in enzymatic activity. We evaluated the association between C677T polymorphism and autism spectrum disorders through a case--control study. In addition, we analyzed the influence of this polymorphism on certain autistic behaviors like complex body movements, self-injury and averted gaze according to the Autism Diagnostic Interview-Revised. The analyses involved 151 children with idiopathic autism spectrum disorder and 100 healthy control children. The frequency of the T allele was 0.38 for the case group and 0.35 for the control group (P=0.77). The genotypic distribution did not show significant differences between cases and controls (P=0.72), nor association between the T allele and selected behaviors. PMID:20440228

  3. Helminth infections predispose mice to pneumococcal pneumonia but not to other pneumonic pathogens.

    PubMed

    Apiwattanakul, Nopporn; Thomas, Paul G; Kuhn, Raymond E; Herbert, De'Broski R; McCullers, Jonathan A

    2014-10-01

    Pneumonia is the leading killer of children worldwide. Here, we report that helminth-infected mice develop fatal pneumonia when challenged with Streptococcus pneumoniae. Mice were chronically infected with either the flatworm Taenia crassiceps or the roundworm Heligmosomoides polygyrus. Upon challenge with a pneumonic type 3 strain of S. pneumoniae (A66.1), the worm-infected mice developed pneumonia at a rate and to a degree higher than age-matched control mice as measured by bioluminescent imaging and lung titers. This predisposition to pneumonia appears to be specific to S. pneumoniae, as worm-infected mice did not show evidence of increased morbidity when challenged with a lethal dose of influenza virus or sublethal doses of Staphylococcus aureus or Listeria monocytogenes. The defect was also present when worm-infected mice were challenged with a type 2 sepsis-causing strain (D39); an increased rate of pneumonia, decreased survival, and increased lung and blood titers were found. Pneumococcal colonization and immunity against acute otitis media were unaffected. Anti-helminthic treatment in the H. polygyrus model reversed this susceptibility. We conclude that helminth coinfection predisposes mice to fatal pneumococcal pneumonia by promoting increased outgrowth of bacteria in the lungs and blood. These data have broad implications for the prevention and treatment for pneumonia in the developing world, where helminth infections are endemic and pneumococcal pneumonia is common. PMID:24952091

  4. Incisional Hernia in Women: Predisposing Factors and Management Where Mesh is not Readily Available

    PubMed Central

    Agbakwuru, EA; Olabanji, JK; Alatise, OI; Okwerekwu, RO; Esimai, OA

    2009-01-01

    Background / Aim: Incisional hernia is still relatively common in our practice. The aim of the study was to identify risk factors associated with incisional hernia in our region. The setting is the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria during a period when prosthetic mesh was not readily available. Patients and Methods: All the women who presented with incisional hernia between 1996 and 2005 were prospectively studied using a standard form to obtain information on pre-hernia (index) operations and possible predisposing factors. They all had open surgical repair and were followed up for 18–60 months. Results: Forty-four women were treated during study period. The index surgeries leading to the hernias were emergency caesarian section 26/44 (59.1%), emergency exploratory laparotomy 6/44 (13.6%), and elective surgeries 12/44 (27.3%). Major associated risk factors were the use of wrong suture materials for fascia repair, midline incisions, wound sepsis, and overweight. Conclusion: For elective surgeries, reduction of weight should be encouraged when appropriate, and transverse incisions are preferred. Absorbable sutures, especially chromic catgut, should be avoided in fascia closure. Antibiotics should be used for complicated obstetric cases. PMID:21483511

  5. Colorectal carcinoma before 40 years of age: prognosis and predisposing conditions.

    PubMed

    Järvinen, H J; Turunen, M J

    1984-07-01

    The prognosis and the occurrence of premalignant conditions were studied in 249 patients with colorectal carcinoma, diagnosed before the age of 40 years, between 1970 and 1979, in Finland. The aim was to evaluate the possibilities for prevention and screening of colorectal carcinoma in young people. The 5-year survival (41%) corresponded to that observed generally in colorectal carcinoma. The therapeutic delay (mean, 8.6 months) was not longer in the advanced stages (Duke's C, D), which comprised 53% of all, than in the localized stages. A premalignant condition occurred in 46 patients (18.5%): familial adenomatous polyposis coli in 18 (7.2%), ulcerous colitis in 11 (4.4%), cancer family syndrome in 9 (3.6%), and miscellaneous conditions in 8 (3.2%) patients. The younger the patient, the more often a premalignant condition was found. Nearly half of the high-risk patients could have been identified earlier. The findings suggest that more emphasis should be placed on the identification, family screening, and treatment of the conditions predisposing to colorectal cancer. PMID:6474085

  6. Prevalence of Low Back Pain Among Nurses: Predisposing Factors and Role of Work Place Violence

    PubMed Central

    Rezaee, Maryam; Ghasemi, Mohammad

    2014-01-01

    Background: Ergonomic factors predispose nurses to low back pain (LBP). Few studies have clarified the role of workplace violence in LBP occurrence. Objectives: The present study was designed to investigate acute and chronic LBP in Iranian nurses and its association with exposure to physical violence as well as its personal and ergonomic risk factors. Materials and Methods: In this analytic cross sectional study, the rate of acute and chronic LBP and contributing factors were investigated among 1246 nurses using a validated questionnaire. Statistical analysis was performed by chi square, student t-test, and logistic regression, to determine the association between independent variables and LBP. Results: In total, 1246 nurses, consisting of 576 (46.23%) males and 670 (53.77%) females, were included. The mean age and the mean years of employment were 31.23 ± 5.33 and 16.18 ± 7.05, respectively. Both acute low back pain (ALBP) and chronic low back pain (CLBP) were associated with physical violence experience. Moreover, acute and chronic LBP were predicted by positive past history of LBP as well as two ergonomic factors, frequent bending and frequent carrying of patients. Conclusions: Besides a history of low back pain and ergonomic factors, physical violence may be considered a contributing factor for acute low back injuries. Special attention to all personal, occupational, and psychological risk factors is recommended. PMID:25717449

  7. Noncatalytic PTEN missense mutation predisposes to organ-selective cancer development in vivo

    PubMed Central

    Caserta, Enrico; Egriboz, Onur; Wang, Hui; Martin, Chelsea; Koivisto, Christopher; Pecót, Thierry; Kladney, Raleigh D.; Shen, Changxian; Shim, Kang-Sup; Pham, Thac; Karikomi, Matthew K.; Mauntel, Melissa J.; Majumder, Sarmila; Cuitino, Maria C.; Tang, Xing; Srivastava, Arunima; Yu, Lianbo; Wallace, Julie; Mo, Xiaokui; Park, Morag; Fernandez, Soledad A.; Pilarski, Robert; La Perle, Krista M.D.; Rosol, Thomas J.; Coppola, Vincenzo; Castrillon, Diego H.; Timmers, Cynthia; Cohn, David E.; O'Malley, David M.; Backes, Floor; Suarez, Adrian A.; Goodfellow, Paul; Chamberlin, Helen M.; Macrae, Erin R.; Shapiro, Charles L.; Ostrowski, Michael C.; Leone, Gustavo

    2015-01-01

    Inactivation of phosphatase and tensin homology deleted on chromosome 10 (PTEN) is linked to increased PI3K–AKT signaling, enhanced organismal growth, and cancer development. Here we generated and analyzed Pten knock-in mice harboring a C2 domain missense mutation at phenylalanine 341 (PtenFV), found in human cancer. Despite having reduced levels of PTEN protein, homozygous PtenFV/FV embryos have intact AKT signaling, develop normally, and are carried to term. Heterozygous PtenFV/+ mice develop carcinoma in the thymus, stomach, adrenal medulla, and mammary gland but not in other organs typically sensitive to Pten deficiency, including the thyroid, prostate, and uterus. Progression to carcinoma in sensitive organs ensues in the absence of overt AKT activation. Carcinoma in the uterus, a cancer-resistant organ, requires a second clonal event associated with the spontaneous activation of AKT and downstream signaling. In summary, this PTEN noncatalytic missense mutation exposes a core tumor suppressor function distinct from inhibition of canonical AKT signaling that predisposes to organ-selective cancer development in vivo. PMID:26302789

  8. Perceptions of predisposing and protective factors for perinatal depression in same-sex parents.

    PubMed

    Ross, Lori E; Steele, Leah; Sapiro, Beth

    2005-01-01

    Increasing numbers of women are choosing to have children in the context of same-sex relationships or as "out" lesbian or bisexual individuals. This study used qualitative methods to assess perceived predisposing and protective factors for perinatal depression in lesbian, gay, bisexual, and queer (LGBQ) women. Two focus groups with LGBQ women were conducted: 1) biological parents of young children and 2) nonbiological parents of young children or whose partners were currently pregnant. Three major themes emerged. Issues related to social support were primary, particularly related to disappointment with the lack of support provided by members of the family of origin. Participants also described issues related to the couple relationship, such as challenges in negotiating parenting roles. Finally, legal and policy barriers (e.g., second parent adoption) were identified as a significant source of stress during the transition to parenthood. Both lack of social support and relationship problems have previously been identified as risk factors for perinatal depression in heterosexual women, and legal and policy barriers may represent a unique risk factor for this population. Therefore, additional study of perinatal mental health among LGBQ women is warranted. PMID:16260356

  9. CERVICAL SPINE SIGNS AND SYMPTOMS: PERPETUATING RATHER THAN PREDISPOSING FACTORS FOR TEMPOROMANDIBULAR DISORDERS IN WOMEN

    PubMed Central

    Bevilaqua-Grossi, Débora; Chaves, Thaís Cristina; de Oliveira, Anamaria Siriani

    2007-01-01

    Aim: The purpose of this study was to assess in a sample of female community cases the relationship between the increase of percentage of cervical signs and symptoms and the severity of temporomandibular disorders (TMD) and vice-versa. Material and Methods: One hundred women (aged 18-26 years) clinically diagnosed with TMD signs and symptoms and cervical spine disorders were randomly selected from a sample of college students. Results: 43% of the volunteers demonstrated the same severity for TMD and cervical spine disorders (CSD). The increase in TMD signs and symptoms was accompanied by increase in CSD severity, except for pain during palpation of posterior temporal muscle, more frequently observed in the severe CSD group. However, increase in pain during cervical extension, sounds during cervical lateral flexion, and tenderness to palpation of upper fibers of trapezius and suboccipital muscles were observed in association with the progression of TMD severity. Conclusion: The increase in cervical symptomatology seems to accompany TMD severity; nonetheless, the inverse was not verified. Such results suggest that cervical spine signs and symptoms could be better recognized as perpetuating rather than predisposing factors for TMD. PMID:19089141

  10. Rme-8 depletion perturbs Notch recycling and predisposes to pathogenic signaling

    PubMed Central

    Gomez-Lamarca, Maria J.; Snowdon, Laura A.; Seib, Ekatarina; Klein, Thomas

    2015-01-01

    Notch signaling is a major regulator of cell fate, proliferation, and differentiation. Like other signaling pathways, its activity is strongly influenced by intracellular trafficking. Besides contributing to signal activation and down-regulation, differential fluxes between trafficking routes can cause aberrant Notch pathway activation. Investigating the function of the retromer-associated DNAJ protein Rme-8 in vivo, we demonstrate a critical role in regulating Notch receptor recycling. In the absence of Rme-8, Notch accumulated in enlarged tubulated Rab4-positive endosomes, and as a consequence, signaling was compromised. Strikingly, when the retromer component Vps26 was depleted at the same time, Notch no longer accumulated and instead was ectopically activated. Likewise, depletion of ESCRT-0 components Hrs or Stam in combination with Rme-8 also led to high levels of ectopic Notch activity. Together, these results highlight the importance of Rme-8 in coordinating normal endocytic recycling route and reveal that its absence predisposes toward conditions in which pathological Notch signaling can occur. PMID:26169355

  11. Correlation of pressure measurements with angiographic characteristics predisposing to hemorrhage and steal in cerebral arteriovenous malfo